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POSSIBLE TOPICS MASTER THESIS AT THE BUILDING PHYSICS SECTION
PROF. B. BLOCKEN, PROF. H. JANSSEN, PROF. S.ROELS, PROF. D. SAELENS
ACADEMIC YEAR 2014-2015
On the next pages you will find the possible topics for a master thesis at the Building
Physics Section of the Department of Civil Engineering. Most topics fit within ongoing
research projects.
Within the Building Physics Section, we investigate and evaluate the coupled heat, air
and moisture transfer in the built environment, with a focus on thermal comfort and air
quality in interior environments and the sustainability and durability of built structures.
Illustrative examples of our research activities are: frost and salt damage in building
materials, air and moisture transport in walls and roofs, in situ determination of
buildings’ energy performance, development of zero-energy buildings, analyses of
driving rain and wind comfort,…
Our research (inter)acts at different levels, from materials over components to buildings
and environments. It furthermore combines experimental and numerical work, and our
section has acquired a strong international reputation on both fronts.
Although there will always be an interaction between the different levels, the proposed
topics are grouped according their main research level:
BWF-1 up to BWF-7:
topics dealing with heat and mass transport in
building materials
BWF-8 up to BWF-13:
topics dealing with heat and mass transport in
building components
BWF-14 up to BWF-18:
topics dealing with energy use and ventilation of
buildings and the built environment
BWF-19 up to BWF-19:
topics dealing with driving rain and wind comfort in
the built environment
As the The Buildings Physics section has developed an extensive network with other
international universities and research institutes, apart from the presented topics, also a
master thesis in the framework of the Erasmus exchange program is a possibility. Our
most important Erasmus-partners within the field of Building Physics are NTNU in
Trondheim, Norway; Chalmers University in Goteborg, Sweden; DTU in Copenhagen,
Denmark and FEUP in Porto, Portugal.
BWF
F-01
Porië
ënblokkade
es in baksteen ten ge
evolge van gipskristalllisatie
Pore clogging
c
of ceramic
ce
bricks
ks by gypsum crystallisatio
c
on
Superv
visor(s):
Assista
ant(s):
Contacct person(s):
Numbe
er of students:
Language of thesis:
Project link:
Study lines:
Hanss Janssen
Jelen
na Todorovic
Jelen
[email protected]
bwk.kuleuven.b
be
1 or 2
English
BWK GT, IRA BTO
In the last few decad
des, a new type
e of efflorescen
nce started to aappear on bricck masonry buildings in the UK,
the Ne
etherlands and in Belgium. Co
ontrary to the common efflorrescence of hig
ghly soluble sa
alts, which easiily
wash off
o during rain events, this ne
ew efflorescencce consists of llowly soluble gypsum, and is therefore high
hly
persisttent. Since the
e problem und
dermines the aesthetic
a
appeaarance of massonry buildingss, it results in a
growin
ng number of complaints fro
om building owners. Althoug
gh gypsum effflorescence ha
as already bee
en
known
n for several de
ecades, the me
echanisms behin
nd this phenom
menon have no
ot yet been unvveiled.
One of the research problems is th
hat gypsum effflorescence can
nnot be induceed under labora
atory condition
ns.
Simple
e laboratory tessts – where briick sample are fed with gypsu
um solution at the bottom, w
which evaporate
es
at the top surface – showed that gypsum
g
crystallizes under thee surface, form
ming subfloresccence instead of
escence. On the other hand, under the sam
me conditions, other salts do precipitate at the surface an
nd
efflore
do form efflorescencce. Even though
h the internal crystallization
c
o
of calcium sulphate does not cause damage
es,
pore precipitation induces porre clogging, wh
hich highly influ
uences the moiisture and gypssum transport.
its in-p
The aiim of this masster thesis is to
o quantitatively
y estimate the pore clogging of bricks, induced by calcium
sulpha
ate (CaSO4 · 2H
H2O) in function
n of concentrattion. In the firsst part of the prroject, gypsum
m solution uptakke
test will
w be performe
ed. At the botttom surface, brick samples w
will be in contaact with gypsum solution, witth
evaporation allowed only at the top
p surface. In th
his way, gypsu m in-pore crysstallization will be induced. Th
he
on of the test, and/or the con
ncentration of gypsum,
g
will in
nfluence the wiidth and densitty of the crysta
alduratio
lization
n front. The se
econd part starrts with the dry
ying of these g
gypsum contain
ning samples, o
only through th
he
upper surface. After reaching a con
nstant weight, two tests will be conducted.. One group off gypsum-loade
ed
es will be subjected to the water
w
uptake te
est, while for th
he other a deccane uptake te
est is performed.
sample
In botth cases, uptak
ke will take pla
ace from the surface
s
where previously evaaporation had occurred. Water
uptake
e test will give us an insight into the gypsum
m dissolution raate. On the oth
her hand, deca
ane is apolar an
nd
does not
n dissolve sallts. Treating th
he gypsum conttaining samplees as a bilayer material, the w
width of crystallization front and deg
gree of pore fillling can be esttimated, from tthe kinetics off decane sorption. Additionally,
um transport, including
i
the d
dissolution in w
water, can follow
w.
numerrical simulation study of gypsu
This master
m
thesis is composed of:
 Literature re
eview on salt transport,
t
calcium sulphate p
properties and analysis of the sorptivity of a
bilayer composite
 Gypsum solution, water an
nd decane upta
ake tests, undeer laboratory co
onditions
 Numerical simulation study
y on gypsum trransport.
Gypsum ssolution
Illustra
ration: Gypsum
m efflorescence (left
(
& center),, laboratory set
etup of gypsum
m solution uptakke test (right)
BWF
F-02
Verg
gelijkende levenscyclu
l
usanalyse van
v
bouwb
blokken op basis van kurk
Comp
parative life cycle
cy
assessm
ment of buildin
ing blocks bassed on cork
Superv
visor(s):
Assista
ant(s):
Contacctperson(s):
Numbe
er of students:
Language of thesis:
Project link:
Study lines:
Hans Janssen,
J
Karen Allacker
TBD
[email protected]
kuleuven.be, [email protected]
hans.ja
1 or 2
Dutch or English
G IRA BTO
BWK GT,
In a quest to counte
eract the global climate chang
ge and resourcce depletion ch
hallenges, the b
building industtry
i ‘rapidly rene
ewable materials’. Rapidly reenewable materials, with straw
w or bamboo a
as
has a keen interest in
nown examples, are said to have
h
to have enormous
e
pote ntial to come tto a more susttainable built enwell-kn
vironm
ment (see www
w.ecobuildingpu
ulse.com/buildiing-materials/g
growing-deman
nd.aspx for add
ditional information). Cork – the ba
ark of the cork oak which can
n be harvested every 10 yearrs – is another illustration, witth
ng from insulattion material to
o cladding soluttion (see the illlustrations below). A new appotenttial uses rangin
plicatio
on of cork is its use as a building block, in which expandeed cork granulees are bonded with a cementtitious binder.
b
Such co
ork building blo
ocks are promo
oted for their eexcellent combination of therrmal and mechanical performance,
p
ass well as for th
heir significant capacity
c
for CO
O2 fixation.
This master
m
projects aims at a com
mparative life cycle
c
assessme nt (LCA) of succh cork buildin
ng blocks. In a
an
introdu
uctory part, the mechanical and
a hygrotherm
mal properties of cork buildin
ng blocks are ccharacterised, tto
define an appropriatte functional un
nit (as comparrative base) an
nd to identify p
potentially equivalent productts.
This characterisation
n focuses on th
he blocks’ mechanical (elasticcity modulus, ccompressive sttrength) and hyermal (thermal conductivity, capillary
c
absorp
ption coefficien
nt) properties. In the key parrt, an LCA of th
he
grothe
cork building
b
blocks and the alternative function--equivalent bloccks will be made. Such LCA
A study will allo
ow
evalua
ating the enviro
onmental impact of these blo
ocks over their whole life cyclle. All life cycle stages are co
overed,, and the LCA study
s
hence includes extractiion of resourcees, production of materials, cconstruction pro
ocess, use
u stage, dem
molition, End-off-Life and all ne
ecessary transp
port. For all liffe cycle stagess all input/output
flows are
a inventoried
d and evaluated (e.g. energy
y use, harmful emissions, watter use, land u
use) for the cork
buildin
ng blocks and its equivalent products.
p
Speccial attention iss given to carb
bon sequestratiion, both from a
metho
odological and an
a analytical po
oint of view.
The prroject contains the following aspects:
a

he existing literrature, to obtain a deeper an d broader know
wledge on all ttopics involved;;
Review of th

Determinatiion of the mech
hanical and hyg
grothermal maaterial propertiees of the cork b
building blocks;;

Life cycle asssessment of th
he cork building blocks, comp
pared to functio
on-equivalent b
building blocks;

Concluding comparison an
nd recommenda
ations for furth
her research
Referrence: Vogtlän
nder JG, van de
er Velden NM, van
v der Lugt P, 2014, Carbon
n sequestration
n in LCA, a pro-posal for
f a new apprroach based on
n the global carrbon cycle; case
ses on wood an
nd on bamboo, International
Journa
al of Life Cycle Assessment 19
9:13–23.
Illustra
ration: raw barkk of cork oak (lleft), expanded
d cork insulation
on (centre), cork
rk as cladding m
material (right))
BWF
F-03
Num
merieke en experimen
e
tele analys
se van zonn
nekokers
Nume
erical and exp
perimental an
nalysis of sola
ar cookers
Superv
visor(s):
Assista
ant(s):
Contacctperson(s):
Numbe
er of students:
Language of thesis:
Project link:
Study lines:
Hans Janssen
J
TBD
[email protected]
kuleuven.be
hans.ja
1 or 2
Dutch or English
G IRA BTO
BWK GT,
In dev
veloped countriies, buildings are
a conditioned
d to preserve th
he comfort and
d health of building occupantts.
This however
h
require
es the consum
mption of fossil fuels, and hen
nce leads to siignificant carbo
on dioxide emissions. In developing
g countries on the other hand, comfort and
d health of buiilding occupants mainly link tto
p
In
ndoor cooking on wood or co
oal results in a strong pollution of the interrior climate, an
nd
food preparation.
thus le
eads to substa
antial complain
nts with relatio
on to comfort aand health. T
The burning off wood and co
oal
moreo
over consumes many valuable
e resources and
d produces sign
nificant carbon dioxide emissiions.
These negative impa
acts of wood/ccoal cooking ca
an be strongly reduced by th
he use of solarr cookers, whicch
apply the heat of th
he sun to heatt food (see illu
ustrations undeerneath). Thee thermal optim
misation of solar
cookerrs is hence high
hly important, and forms the core topic of tthis project. Th
he performance of some generic mo
odels will be co
ompared based
d on simulations and experim
ments, with focu
us on the therm
mal efficiency of
the co
ookers. In a su
ubsequent step
p, the aim is to
o improve the ssolar cooker deesign to make even better usse
of the solar radiation
n.
The prroject contains the following aspects:
a

eview: in orderr to obtain a brroader and deeeper knowledgee, the existing literature on th
he
Literature re
topic is revie
ewed;

Implementa
ation: simulatio
ons for solar cookers
c
are deeveloped based
d on an existing package fo
ort
hermal build
ding simulation
n;

Experimentss: lab and in situ
s
experimentts are perform
med to validate
e the numerical models for th
he
solar cookerrs;

Simulation study:
s
an exten
nsive simulation study will ind
dicate which ellements contrib
bute to the the
ermal efficiency of the cooke
ers, which are then used to o
optimize their p
performance;
Illustratio
on: various type
pes of solar coo
okers: panel (lef
eft), box (centre
re), parabolic (rright)
BWF
F-04
Kara
akterisatie van
v
vochte
eigenschap
ppen op bassis van dyn
namische
expe
erimenten en
e inverse modellerin
ng
Chara
acterization of
o hygric prop
perties via dy
ynamic metho
ods and invers
rse modelling
g
Superv
visor(s):
Assista
ant(s):
Contacctperson(s):
Numbe
er of students:
Language of thesis:
Project link:
Study lines:
Hans Janssen,
J
Staf Roels
R
Evy Ve
ereecken
Evy.Ve
[email protected]
1 or 2
Dutch or English
G IRA BTO
BWK GT,
Moistu
ure transfer in building materials is a majo
or determinant for the durab
bility and susta
ainability of bu
uilt
structu
ures, the achie
evement of a healthy indoorr environment,, the energy cconsumption, e
etc. To simulate
moistu
ure transfer, the moisture storage and moistture transport properties of b
building materials are required.
Curren
ntly, these pro
operties are, however, not defined
d
for thee full moisture range. In the
e mid-saturatio
on
range,, knowledge on the hygric properties
p
is lacking. In addittion, ad- and desorption me
easurements are
merge
ed. Furthermore
e, the current measurement
m
techniques
t
req uire weeks till months of exp
periments.
In thiss project, the potential
p
to dettermine the hy
ygric material p
properties via d
dynamic hygricc measuremen
nts
in com
mbination with inverse modelling will be sttudied. Inversee modelling aim
ms to find the
e unknown input
param
meters (in this case
c
the hygricc material properties) resultin
ng in a known o
output (in this case the resullts
of a dynamic
d
hygricc experiment),, as also expla
ained in the ffigure below. Since dynamicc measuremen
nts
deman
nd a shorter measurement
m
period, this sttrategy will ressult in a reduction of the ttime required to
characcterize material properties. In
n addition, tho
ose dynamic m
measurements could give info
ormation on th
he
hygric behaviour in the mid-saturattion range. In a first part of th
he thesis, the p
possibilities of invers modellin
ng
e explored base
ed on theoretical material pro
operties. The aiim of this part is the developm
ment of a robu
ust
will be
inverse
e identification algorithm. To gain insight on
n the propertiees in the mid-saaturation range
e and on the ad
dand desorption proccess, dynamic measurementss will be propo
osed and implemented. In a
an experimenttal
t inverse iden
ntification algorrithm will be ap
pplied for real building materrials and will be
e validated.
part, the
The th
hesis contains the
t following asspects:

Literature re
eview: in orderr to obtain a brroader and deeeper knowledgee, the existing literature on th
he
topic is revie
ewed;
Numerical study: Establishment of a virtual testb
bed to scan the possibilitiies of dynam
mic

measureme
ents in combin
nation with inv
verse modellin
ng. To this aim
m, in a first step a materiial
database is set up. These properties will be used to sim
mulate dynamicc measurementts;
al study: Dynamic experime
ents are perfo
ormed to usee as an input in the inversse
Experimenta

characteriza
ation strategy.
Invers
se modelling:: (1) a dynam
mic experimen
nt is performe
ed, (2) the num
merical simullation that is in
agree
ement with the
e experimenta
al results give
es the hygric m
material prop
perties.
BWF
F-05
Stud
die van voch
hteigensch
happen op basis
b
van o
over-hygro
oscopische desiccatorren da
ampdiffusiietests.
Invesstigation of moisture
m
prope
perties based on overhygro
oscopic desicccators and di
diffusion cupss
Superv
visor(s):
Assista
ant(s):
Contacctperson(s):
Numbe
er of students:
Language of thesis:
Project link:
Study lines:
Hans Janssen
J
Evy Ve
ereecken
Evy.Ve
[email protected]
1 or 2
Dutch or English
G IRA BTO
BWK GT,
Moistu
ure is often a key
k factor in da
amage or disco
omfort in buildi ngs, and the ccorrect design o
of new building
gs
hence requires a re
eliable assessm
ment of moistu
ure transfer in
n building matterials. Such assessment necessita
ates hygric ma
aterial propertie
es for moisture
e storage and transport. Currrent measurem
ment technique
es
allow measuring mo
oisture storage
e and transporrt only for rath
her dry statess (hygroscopic range) and fo
or
ear-capillary range). For moissture states in between, usuaally interpolatio
on, based on th
he
rather wet states (ne
edge of the pore structure, iss applied. The correctness of such interpolaation remains d
debated though
h.
knowle
In thiss project, we will
w attempt to develop
d
new measurement teechniques for m
moisture storag
ge and transporrt,
based on psychrome
etry. Psychrom
meters allow dettermining relattive humidities near to 100 %
%, exactly in that
mediate range that
t
currently remains
r
unmea
asured. Use off psychrometerrs in desiccato
ors – sealed po
ots
interm
with a specific relative humidity in
nside, meant to
o determine m
moisture storag
ge (left figure) – and diffusio
on
cups – combinationss of sealed potts at different relative humid
dities, meant to determine m
moisture transffer
(right figure) – will thus enable wider
w
measurem
ment of moistu
ure storage and transport. The experimenttal
w be combined
d with a numerical part in wh
hich the influen
nce of experim
mental errors an
nd measurement
part will
uncerttainties on the simulated hygrric performance
e of building ellements will bee studied.
The th
hesis contains the
t following asspects:

Literature re
eview: in orderr to obtain a brroader and deeeper knowledgee, the existing literature on th
he
topic is revie
ewed;

Experimenta
al study: Overrhygroscopic de
esiccators and cup tests will be developed
d. Both ad- an
nd
desorption measurementss will be perfo
ormed. Thereto
o, also more sstandard techn
niques (standard
p
desiccator, pressure plate tests) will be performed.
s
The inffluence of exp
perimental erro
ors and measurement unce
ertainties will b
be

Numerical study:
studied. Thereto, in a first step, the errors/uncertain
nties will be deefined. Next, tthe influence of
uilding elementts will be studie
ed
these errorss/uncertainties on the simulatted hygric perfformance of bu
based on a numerical simu
ulation model.
a)
b)
a) Desicc
cators, b) cup
p test.
BWF
F-06
Ontw
werp van ee
en in situ experiment
e
t voor het b
bepalen va
an vocht- en
afloo
opgedrag bij
b poreuze bouwmate
erialen
Desig
gn of an in sittu experimentt to determin
ne the moistu
ure and runoff
ff behaviour o
of porous
wallss
Superv
visor(s):
Assista
ant(s):
Contacctperson(s):
Numbe
er of students:
Language of thesis:
Project link:
Study lines:
Staf Ro
oels
Thijs Van
V den Brande
e
thijs.va
[email protected]
@bwk.kuleuven..be
1 or 2
Dutch or English
I
BWK, IRA
ased moisture levels in poro
ous building fa
açade materia ls can result in durability p
problems of th
he
Increa
materiial. Damage may
m occur due to freeze-thaw
w cycles, surfacce soiling, discoloration by effflorescence an
nd
moistu
ure induced sa
alt migration. In
I case of mo
onumental build
wever difficult to quantify th
he
dings it is how
moistu
ure behaviour or
o determine iff the wall got a hydrophobic ffinish without aany knowledge
e on the materiial
properrties.
Over the
t last decade
es the Karsten tube has been
n used as a te sting device to
o measure in ssitu the moisture
transfe
er properties of
o porous wallls (see figure)). This non-deestructive meth
hod gives reprroducible resullts
when applied accura
ately. It gives however
h
little physical
p
interp
pretation and th
he process is vvery sensitive to
urate positioning of the tube.
inaccu
Aim off this master th
hesis is to deve
elop a new in siitu experimentaal device to meeasure the moiisture and runo
off
behaviour of a porous wall. Using needles with different diam
meters, a drop is placed on tthe wall and th
he
ed. The goal iss to compare tthis experiment with a 2D m
model of the wa
all
behaviour of that drrop is monitore
quid drop and see whether th
he liquid transfer properties of the wall can
n be determine
ed based on th
he
and liq
runoff behaviour of the
t droplet.
Appl
plication of the Karsten
K
tube on site (Sint-Ma
artinusbasiliek, Belgium). Thee tube is fixed to the wall with
h
adhessive putty, after
er that the tube
e is filled with water
w
and the hheight of the w
water column iss monitored oveer
time. On the
e right, the wett
tting region aroound the tube is shown.
BWF
F-07
Duurrzaamheid van extern
ne luchtdic
chtingstape
es voor laag
g-energie h
houtskelettwoningen: experimentele
e studie
An ex
xperimental study
s
on the durability
d
of external
e
adhe
esive tapes fo
for timber fram
me passive
house
es
Superv
visor(s):
Assista
ant(s):
Contacctperson(s):
Numbe
er of students:
Language of thesis:
Project link:
Study lines:
Staf Ro
oels
Jelle La
angmans
[email protected]
1 or 2
Dutch or English
G IRA BTO
BWK GT,
Today, labels introdu
uced to certify standardised low
l
energy buiildings, such as ‘Passivhaus’ in Germany an
nd
‘Minen
nergie’ in Switzerland, are beccoming increassingly applied aacross Europe. Both labels exxplicitly require a
thresh
hold level of airttightness (0.6 air changes pe
er hour (ACH) aat 50 Pa). For ttimber frame p
passive houses in
Belgium, this require
ement is comm
monly achieved
d by carefully sealing all joiints in betwee
en the structurral
boardss.
An on
ngoing research
h project at th
he Building Ph
hysics Section in collaboratio
on with the in
ndustrial partner
REDCO
O nv explores the
t hygrotherm
mal requiremen
nts for exterior air barrier sysstems. The focu
us of the proje
ect
is on the
t optimisation
n of the materiial properties fo
or this techniqu
ue. However, aan important re
esearch questio
on
in the context rema
ains the durab
bility and life-tiime expectatio
on of the adheesive tapes to
o seal the join
nts
between the structtural boards. Exterior air barrier
b
are exxposed to high temperature
e and humidity
ations. Studying the influence
e of these para
ameters on thee sealed joints will be the corre of the present
fluctua
thesis..
The th
hesis concerns an experimen
ntal study verifying the duraability and agin
ng of sealed joints. The ma
ain
focus will be on the influence of th
he air permeab
bility and mech
hanical propertties of taped jo
oints in betwee
en
ng boards under climatic varriations. The thesis studentt(s) are expectted to set-up a
an experimenttal
buildin
proced
dure to test th
he above-menttioned aspects under variouss conditions. T
The student ca
an apply precisse
measu
urement equipm
ment available
e at both the Laboratory
L
of Building Physiics (e.g. Air pe
ermeability tesstsetup, Figure left) an
nd the R&D lab
boratory of the industrial partn
ners (e.g. heatt-rain chamber,, Figure right).
Left:
L
Air permea
ability test-setu
up and right: he
heat-rain climate
te chamber.
BWF
F-08
Hygrrothermische prestatiie-analyse van koude
e zolders
Hygro
othermal perf
rformance ana
alysis of cold
d attics
Superv
visor(s):
Assista
ant(s):
Contacctperson(s):
Numbe
er of students:
Language of thesis:
Project link:
Study lines:
Hans Janssen
J
TBD
[email protected]
kuleuven.be
hans.ja
1 or 2
Dutch or English
G IRA BTO
BWK GT,
Cold attics
a
are a popular solution for the insulattion of the roo
of construction in Scandinavian countries. IIn
such cold
c
attics, insu
ulation is place
ed on the attic floor instead o
of in the roof iitself, which le
eads to generallly
colder conditions in the
t attic, hence the name. Su
uch solution is of interest wh
hen thermally u
upgrading atticcs,
ecute. But alsso newly built dwellings are progressively m
more often con
nstructed with a
as it iss simple to exe
cold atttic.
Such cold
c
attics are however
h
very sensitive
s
for the infiltration off warm and hu
umid interior airr, which may re
esult in mould growth
h and wood rott in the attic sp
pace. The expeeriences in Sweeden teach us tthat a dedicate
ed
ventila
ation strategy is required to avoid
a
damage in these cold atttics. Despite tthese foreign e
experiences, co
old
attics are suggested more and morre frequently in
n Belgium: thee tighter requireements for the
e thermal perfo
ore of buildings and
a the rising costs
c
of energy consumption p
play an importaant role in thatt evolution. An
nd
mance
while the
t Swedish gu
uidelines emph
hasize a good ventilation
v
straategy, no functtional guideline
es are in place in
Belgium.
This projects
p
aims att studying the hygrothermal benefits and d
damages of cold attics in Belgium: the que
estion to
o answer is wh
hether this atticc solution can be safely appl ied in the Belg
gian climate. In
n a first part, a
an
existin
ng analytical model for the te
emperature, rellative humidityy and ventilatio
on flows in atticcs is to be com
mpleted. Application of
o this simulatio
on model then allows an asssessment of thee consequence
es of (better) ind attic floors, and
a an evaluattion of possible
e solutions. Co
omplementarilyy, results of me
easurements are
sulated
processsed and interp
preted, to supp
port the theore
etical investigattion. Confrontaation of the nu
umerical and experime
ental results wiill then finally permit
p
to formu
ulate robust atttic solutions.
The th
hesis consists of
o the following tasks:

Literature re
eview concerning moisture prroblems in (un))vented (cold) attics

Completion of an analytica
al model for the
e hygrothermaal behaviour of attics

Processing and
a interpretattion of selected
d hygrothermall measurementts in attics

Application of the numericcal model for th
he assessment of attic and/orr roof solutionss

n of robust solu
utions for the th
hermal insulatio
on of attic consstructions
Formulation
Illustration
n: problems witth wood rot (lef
eft & right) en m
mould growth ((center) in cold
d attics
BWF
F-09
Kan binnenisolatie veilig worden
w
toe
egepast ind
dien houte
en vloerbalk
ken zijn
opge
elegd in de wand?
A hyg
grothermal study of woode
en beam ends
s in masonry walls insulatted with interrior insulation
Superv
visor(s):
Assista
ant(s):
Contacctperson(s):
Numbe
er of students:
Language of thesis:
Project link:
Study lines:
Staf Ro
oels
Evy Ve
ereecken
[email protected]
uven.be
1 or 2
Dutch or English
G IRA BTO
BWK GT,
The la
ast decade, energy
e
require
ements becam
me more and more stringeent. To improvve the therm
mal
performance of exissting masonry walls, both interior and exxterior insulatiion can be ap
pplied. Althoug
gh
exterio
or insulation ha
as a higher pottential and less hygrothermal risks, for somee buildings inte
erior insulation is
the on
nly possibility. Although
A
a lot of progress ha
as been made ffor a reliable aapplication of in
nterior insulatio
on
and ba
asic guidelines are available, one of the issues remains un
nsolved so far:: what about tthe risk on woo
od
rot wh
hen interior insu
ulation is applie
ed on masonry
y walls with woo
oden beam ends incorporated
d in the wall.
To eva
aluate the risk and possible solutions
s
both numerical and experimental work will be p
performed in th
his
master thesis. The numerical
n
work
k includes therrmal and hygri c simulations o
of the wooden
n beam ends fo
for
ent boundary conditions.
c
In the
t experimenttal part, a massonry wall will be built in the
e hot box / co
old
differe
box (ssee figure below
w) at the laborratory of the bu
uilding physics section. In thiis set-up differrent solutions fo
or
woode
en beam ends incorporated in the masonrry wall will be constructed. By imposing ffixed indoor an
nd
outdoo
or conditions the hygrotherm
mal conditions around
a
the wo
ooden beam en
nds can be mo
onitored and th
he
risk on
n mould growth
h and wood rott evaluated.
BWF
F-10
De im
mpact van uitvoeringskwaliteit op de thermische pre
estatie van wand- en
dake
elementen
Quant
ntifying the im
mpact of work
kmanship on the thermal p
performance
e of wall and rroof
comp
ponents
Superv
visor(s):
Assista
ant(s):
Contacctperson(s):
Numbe
er of students:
Language of thesis:
Project link:
Study lines:
Staf Ro
oels
A-H. Deconinck
D
anhele
[email protected]
@bwk.kuleuven
n.be
1 or 2
Dutch or English
G IRA BTO
BWK GT,
e debate on en
nergy efficient dwellings, an accurate know
wledge of the aactual thermal performance of
In the
our bu
uildings’ fabricc is essential. Currently, the
e thermal qua lity of the building envelope is awarded a
performance label during
d
the desiign phase. Thiis label is baseed on theoretiical calculation
ns and does not
n with the re
eality of the construction
c
process where workmanship
p issues, moissture infiltration,
reckon
undesired air flows, etc.
e can influen
nce the therma
al performance of building eleements in a negative way. Th
his
t
performance of wall and roof com
mponents due to undesired a
air
master thesis treats the reduced thermal
t
the bu
uilding element.
flows through
Rotatio
onal air flows around insula
ation layers orr wind washing
g in roofs havve a baleful in
nfluence on th
he
therma
al performance
e of wall and roof
r
componen
nts and induce a discrepancyy between the as-built U-valu
ue
and th
he theoretically calculated U-v
value [1]. Causses for these ph
hysical phenom
mena in the acttual constructio
on
processs can be foun
nd on building
g sites by visu
ual inspectionss. The focus o
of these inspecctions is on th
he
construction of the insulation and airtight layers of roof and w
wall componentts. This masterr thesis can ad
dd
observ
vations to the existing
e
set of inspections.
i
Differen
nt constructions
s of a cavity wa
all. Source: [2], [3]
The in
nsulation layer of
o a cavity wall is designed as
s a continuous layer adjacentt to the inner w
wall leaf. Poor
workm
manship, howev
ver, shows thatt air gaps aroun
nd the insulatio
on layer often o
occur on site in
n practice.
Paralle
el to the inspecctions on site , this master the
esis intents to q
quantify the im
mpact of rotatio
onal air flow an
nd
wind washing
w
on the
e thermal performance of walll and roof com ponents. This iis done by the use of
numerrical models. Th
he latter contain a lot of assu
umptions conceerning friction lo
osses, air flow resistances ,
etc. Fe
eedback from the
t on-site insp
pections will be
e used as an in
nput for measu
urements speciffying those
valuess in more detaill.
[1]
[2]
[3]
J. Lecompte
e, “De invloed van
v natuurlijke convectie op d
de thermische kwaliteit geïsoleerde
spouwconsttructies,” KU Le
euven, 1989.
G. Verbeeck
k and S. Roels, “TETRA-PROJE
ECT BEP2020. Betrouwbare eenergieprestatie van
woningen. Naar
N
een robuu
uste en gebruik
kersonafhankel ijke performan
ntie. N°110189.” Provinciale
Hogeschool Limburg, KU Leuven,
L
pp. 1–3
38, 2012.
S. Saelen, “Uitvoering
gskwaliteit als essentiële paraameter voor dee energetische prestatie van
reside
entiële nieuwbo
ouw.,” KU Leuv
ven, 2012.
BWF
F-11
Inno
ovatieve inttegratie va
an photovoltaische en
nergie in ge
evels
Innov
vative integra
ation of photo
tovoltaics in cladding
c
syste
ems
Superv
visor(s):
Assista
ant(s):
Contacctperson(s):
Numbe
er of students:
Language of thesis:
Project link:
Study lines:
Dirk Saelens
TBD
kuleuven.be
[email protected]
1 or 2
English
BWK, ENE, IRA
In order to reduce th
he primary ene
ergy use of buildings the use o
of renewable eenergy plays an
n important role.
o the techniqu
ues to integratte PV in the clladding system
m is replacing the glazing un
nit with a high
hly
One of
insulatted PV panel. In the examp
ples shown in Figure 1, the insulation is p
provided by ad
dding a vacuum
insulattion panel (VIP). The integrration of PV and
a
VIP in clad
ddings howeveer poses different challenge
es,
mainly
y related to the
e high temperattures that may
y occur in the syystem.
In thiss master thesis students will design,
d
assess and test severaal options to m
make such a cla
adding system.
The ob
bjectives of the
e thesis are:





to develop a thermal mode
el describing th
he performancee of the claddin
ng system
analyse the impact of the temperatures on
o the energy yield of the PV
V-system
analyse the durability of the
t VIP (e.g. th
he joints of thee VIP) and PV unit (e.g. dela
amination) under
extreme tem
mperatures
design a sy
ystem that prov
vides the best overall energyy performancee in terms of in
nsulation quality
including thermal bridging
g , risk of delam
minating of the PV, energy yieeld of the PV, ...
develop a measurement
m
setup
s
to the cladding system
ms and test the designed system under re
eal
climatic con
nditions
o will provide the samples for testing an
This thesis subject is in collabora
ation with Dow
w Corning who
nd
backgrround informattion on the systtem.
FIG 1. Schematic
Sc
repre
esentation of proposals
pr
to inge
gegrate PV in th
he cladding sysstem
BWF
F-12
Intre
egratie van
n vacuüm is
solatie pan
nelen (VIP)) in gevelsy
ystemen
Integ
gration of vac
cuum insulatio
ion panels (VI
VIP) in claddin
ng systems
Superv
visor(s):
Assista
ant(s):
Contacctperson(s):
Numbe
er of students:
Language of thesis:
Project link:
Study lines:
Dirk Saelens
TBD
kuleuven.be
[email protected]
1 or 2
English
IRA
Facade
es consist of a sequence of opaque and tran
nsparant parts.. In some high rise buildings a uniform
façade
e is desired. In order to obtain
n this uniform façade,
f
shadow
w boxes are ussed in cladding systems to
mimic the esthetical aspect of norm
mal glazing unitts. Usually, the opaque parts are insulated w
with traditional
w
has the drawback
d
that the thickness o
of the façade vvaries between transparent
insulattion materials which
and op
paque parts. To
o overcome thiis problem, the
e traditional inssulation layer m
may be replaced
d with a VIP.
The in
ntegration of VIIP in claddings however posess some challen
nges, mainly re lated to the the
ermal bridging
and th
he high tempera
atures that ma
ay occur in the system.
In thiss master thesis students will design,
d
assess and test severaal options to m
make such a cla
adding system.
The ob
bjectives of the
e thesis are:





to develop a thermal mode
el describing th
he performancee of the claddin
ng system
analyse the impact of the temperatures on
o the stressess in the facade
analyse the durability of th
he VIP (e.g. the
e joints of the VIP)
design a sysstem that prov
vides the best overall
o
energy p
performance in
n terms of insulation quality
including thermal bridging
g , risk of glass failure (thermaal stress) and V
VIP failure
develop a measurement
m
se
etup to the cladding systems and test the d
designed system
m under real
climatic con
nditions
This th
hesis subject iss in collaboratio
on with Dow Co
orning who willl provide the saamples for testting and
backgrround informattion on the systtem
FIG 1. Scchematic repres
esentation of a proposal
p
to inte
tegrate VIP in tthe cladding sys
ystem
BWF
F-13
Ontw
werp en detaillering van
v
een pre
efab-gevelssysteem vo
oor de therrmische
reno
ovatie van een
e
bestaand kantoorrgebouw
Desig
gn of prefabric
icated façade
e elements forr the thermall renovation o
of an existing
g office
buildiing
Superv
visor(s):
Assista
ant(s):
Contacctperson(s):
Numbe
er of students:
Language of thesis:
Project link:
Study lines:
Staf Ro
oels
Jelle La
angmans, Liesb
beth Staepels
[email protected]
uven.be, [email protected]
wk.kuleuven.be
e
1 or 2
Dutch or English
G IRA BTO
BWK GT,
ngs are responssible for a large
e share of the energy use an
nd CO2-emissio
ons. But where recent stringent
Buildin
energy
y requirementss resulted in a lot of progresss for new bui ldings, improv ing the existin
ng building stocck
remain
ns a huge challenge. The buiilding stock of the University of Leuven is a typical example. The current
state and thermal performance
p
of
o the building
gs is often in painful contraast with the ttechnological e
en
scientiific knowledge available by itss users.
The aim of this masster thesis is to
t design a lig
ghtweight façad
de system for the renovatio
on of one of th
he
c
of the Celestijnenlaa n. The work iss part of the research proje
ect
typicall concrete buildings at the campus
‘HOLD
DUB: Holistic sustainable con
nstruction’, a joint
j
collaboraation between different depa
artments of th
he
Faculty
y of Engineerring. The projject wants to combine thee available kno
owledge en e
expertise in th
he
departtments to tran
nsform one of the existing buildings
b
of KU
U Leuven into a pilot projectt on sustainab
ble
renova
ation of existin
ng buildings. Th
he academic year
y
2013-2014
4 a monitoring campaign and
d exploration o
on
possib
ble renovation tracks has bee
en performed for
f this buildin
ng. This maste
er thesis is a fo
ollow up on th
his
work and aims at the
t
design and
d detailing of a façade systtem that can be prefabricatted to thermallly
ate the existing
g building witho
out disturbing the activities w
within the build
ding. The main focus will be o
on
renova
the de
esign and dettailing of the prefabricated elements and
d their junctio
ons. In addition the therm
mal
performance of a sta
andard elemen
nt will be nume
erically simulatted to get a co
orrect estimation of the finallly
ved overall improvement.
achiev
Left: the envisaged building,
b
right: example of a renovation
r
baseed on exterior light weight fa
açade element
BWF
F-14
Het gelijktijdig
g
g verbetere
en van klimaatconditie
es en energ
gieprestatiies van
monumenten: het
h Erasmu
ushuis in Anderlecht
A
Simulltaneously im
mproving consservation con
nditions and e
energy perforrmance of mo
onuments: th
he
Erasm
mus house in Anderlecht
Superv
visor(s):
Assista
ant(s):
Contacctperson(s):
Numbe
er of students:
Language of thesis:
Project link:
Study lines:
Staf Ro
oels
TBD
uven.be
[email protected]
1 or 2
Dutch
G IRA BTO
BWK GT,
The Errasmus house in Anderlecht dates
d
from 146
60 and is one o
of the eldest go
othic houses in Brussels. It wa
as
not acctually the housse of Erasmus, but the great humanist stayeed as a guest in the house fo
or a short perio
od
to enjo
oy the country
yside (at that moment
m
Anderrlecht was a sm
mall village of 300 inhabitantts). Although h
he
didn’t stay long, he made
m
a great im
mpression and the building b
became famouss as the house where the great
B
of the 20th century,, the Erasmus h
house has been
n restored to the way it looke
ed
Erasmus had lived. Beginning
21, the moment Erasmus lived
d in the house. Today, the ho
ouse hosts a m
museum surrou
unded by a mo
ost
in 152
wonde
erful garden.
But, as for many mo
onumental build
dings, the climatic conditionss in the house are not alwayss optimal for th
he
ble collection and
a
neither is the energy performance
p
off the building. Aim of this m
master thesis is
valuab
twofold. On the one
e hand analyse
e the current situation and p ropose amendments to imprrove the climattic
ollection and on
n the other han
nd make suggeestions to redu
uce the energyy consumption of
conditions for the co
uilding, while maintaining
m
the comfort of the
e visitors. The sstudy could con
ntain the follow
wing steps:
the bu
1.. general aud
dit of the Erasm
mus house in its current statte (description of heating sysstem, measurin
ng
air tightnesss, IR-images,…
…)
2.. analysis and
d interpretation
n of data loggin
ng (performed by the museum
m)
3.. compiling th
he required clim
matic conditions in view of thee collection of the museum
4.. simulation of
o the thermal dynamic beha
aviour of the b
building based on BES-mode
el (BES: Buildin
ng
Energy Simulation) both fo
or the current state
s
as for posssible alternativves
5.. based on all previous work
k, propose imp
provements for building fabricc, HVAC-system
m,…
The work
w
will be don
ne in close collaboration with
h the conservattor of the Erasmus house as well as with th
he
‘Dienstt Monumenten en Landschappen van het Brrussels Hoofdsttedelijk Gewestt’.
BWF-15
Het modelleren van warmteverliezen tgv luchtinfiltratie/-exfiltratie mbv
systeemidentificatie-methoden
Modelling heat losses due to air infiltration/exfiltration using system identification methods
Supervisor(s):
Assistant(s):
Contactperson(s):
Number of students:
Language of thesis:
Project link:
Study lines:
Staf Roels
Geert Bauwens
[email protected]; [email protected]
1 or 2
Dutch or English
BWK GT, IRA BTO
In order to reduce the energy use of dwellings, different countries have put forward more strict regulatory
demands to the energy performance of new and renovated buildings. Without exception, this performance
is calculated in the design phase. Several studies, however, show that the as-built performance can differ
significantly from this theoretical value. The energy performance of buildings comprises three parts: building
fabric, building services and building usage. Hence, the characterisation of the thermal performance of the
building fabric represents an important first step towards bridging the gap between the designed energy
performance and the performance that is actually achieved upon completion.
Heat loss through a building fabric essentially consists of two components: transmission heat losses and
natural ventilation heat losses (infiltration/exfiltration). The latter arises due to a combination of thermal
stack and wind induced pressure differences over the building envelope. A leaky envelope will lead to
important heat losses due to air flowing through it, which subsequently needs to be heated to comfort
conditions. Studies show that the heat loss due to air infiltration and exfiltration can represent an important
share of the total heat loss.
The aim of this thesis is to describe the actual air change rate through the building envelope, taking place
during a heating experiment or during normal use of the building. Simplified models with physical relevance
will be defined and fitted to measurement data. For instance, a model could describe the air flow as a direct
function of weather conditions as e.g. outdoor air temperature, wind speed and direction.
An important part of the thesis will be devoted to a thorough analysis of simulated and real measurement
data (e.g. tracer-gas tests will be performed) of air flows occurring in representative dwellings under typical
weather conditions.
This thesis has been put forward in the framework of the collaborative project between KU Leuven and
Knauf on “Investigating the gap between real and predicted/expected thermal performances of buildings”. It
also inspired by recent and ongoing international activity in the framework of the IEA EBC Annex 58 project:
“Reliable building energy performance characterization based on full scale dynamic measurements”.
BWF-16
Naar een karakterisatie van de thermische prestatie van gebouwen op basis
van eenvoudig metingen
Towards a thermal performance characterisation of buildings based on crude measurement
data
Supervisor(s):
Assistant(s):
Contactperson(s):
Number of students:
Language of thesis:
Project link:
Study lines:
Staf Roels
Geert Bauwens, Liesje van Gelder
[email protected]; [email protected]
1 or 2
Dutch or English
BWK GT, IRA BTO
In order to reduce the energy use of dwellings, different countries have put forward more strict regulatory
demands to the energy performance of new and renovated buildings. Without exception, this performance
is calculated in the design phase. Several studies, however, show that the as-built performance can differ
significantly from this theoretical value. The energy performance of buildings comprises three parts: building
fabric, building services and building usage. Hence, the characterisation of the thermal performance of the
building fabric represents an important first step towards bridging the gap between the designed energy
performance and the performance that is actually achieved upon completion.
This thesis will investigate the possibility, on the basis of measurement data acquired during on-board
monitoring campaigns (buildings in use and heated by installed services), to estimate the building
envelope’s thermal performance (e.g. heat transfer and solar aperture coefficients). To that end, simple
models with physical relevance will be defined, and in a subsequent step fitted to available measurement
data. The result is e.g. a model that describes the heating power demand of a dwelling as a function of its
characteristics, monitored indoor and outdoor air temperatures, solar radiation, wind speed and direction,
user behaviour characteristics, etc. The building is then characterized by the physically relevant parameters
that make up these models.
In a First part, the thesis will include an elaborate data analysis of readily available measurement data. The
final aim is to characterise the investigated dwellings and to optimize the characterisation process towards
result (what can we characterise and to what uncertainty?) and practice (which measurements are
necessary to obtain reliable results? How long do we have to measure for?).
This thesis has been put forward in the framework of the collaborative project between KU Leuven and
Knauf on “Investigating the gap between real and predicted/expected thermal performances of buildings”. It
also inspired by recent and ongoing international activity in the framework of the IEA EBC Annex 58 project:
“Reliable building energy performance characterization based on full scale dynamic measurements”.
BWF-17
Warmterecuperatie uit rioolwater voor verwarming en warm water
Heat recovery from sewer systems for domestic heating and hot water
Supervisor(s):
Assistant(s):
Contactperson(s):
Number of students:
Language of thesis:
Project link:
Study lines:
Dirk Saelens
Thijs Vandenbrande
[email protected], [email protected]
1 or 2
Dutch or English
NA
BWK, ENE, IRA
World-wide 30 to 40% of the total energy use is used for operating the building stock. A more efficient use
of buildings can reduce the economic cost and eliminate greenhouse gas emissions. Because of the
environmental impact of the depletion of energy resources, the interest in sustainable, low impact
alternatives for energy increased considerably in the past years. As the temperature of waste water is
usually higher than that of the water supply a potential track to decrease the energy consumption is to
recover energy from waste water by using a heat exchanger built-in in the sewer system and coupling it to
a heat pump.
In this master thesis students will develop a model for such a sewer heat recovery system and couple it to
an existing dynamic building energy simulation tool. This includes the development of code and the
collection of all relevant boundary conditions such as mass flow rates, temperature of waste water and
frequency of drainage. Subsequently, using yearly simulations the system will be evaluated in terms of the
Coefficient of Performance (COP) or the Heating Season Performance Factor (HSPF), the maximal power
and the potential energy reduction compared against traditional systems. In the first half of 2014 such a
heat recovery system will be build in Leuven and linked to a collective heating system. If the measurements
become available the model may be compared against these data.
In the figure below, a schematic representation of a heat recovery system for sewers is depicted. On the
left, waste water from the central collection tube is transferred to a reservoir and filtered. This waste water
is then transferred through a heat exchanger which exchanges heat with a secondary loop that connects to
the evaporator of a heat pump. This heat pump increases the temperature level and stores the heat ina
buffer reservoir. The required heat to fulfil the needs for zone heating and domestic hot water use is then
taken from this reservoir by using heat exchangers.
Sewer + filters
Heat exchanger
Schematic representation of a heat recovery system for sewers
Heat pump
Reservoir +
heating system
BWF
F-18
Centtrale of dec
centrale energievoorz
ziening op ccampus Arrenberg?
Centrral or decentrral energy sup
pply on the Arenberg
A
cam
mpus?
Superv
visor(s):
Assista
ant(s):
Contacctperson(s):
Numbe
er of students:
Language of thesis:
Project link:
Study lines:
Dirk Saelens
beth Staepels, Christina
C
Proto papadaki
Liesb
[email protected]
kuleuven.be, [email protected]
en.be
1 or 2
Dutch or English
BWK, ENE, IRA
The en
nergy use of th
he building stocck of the KU Le
euven in generaal and that of tthe Arenberg C
Campus in
particu
ular is not exacctly an example
e of good practtice. The quality
ty in terms of ssustainability an
nd technologica
al
innova
ation is in stron
ng contrast to the
t technologiccal and scientifiic knowledge aavailable to the users of the
buildin
ngs. This thesiss topic is part of
o the HOLDUB project aiming
g at finding solu
ution to make tthe campus
more sustainable.
s
The ob
bjective of this thesis is to foccus on the energy production on the campu
us. Two main options are
availab
ble: when the current
c
boilers are due for rep
placement, theey are replaced
d with the best available
curren
nt technology or
o a central pow
wer plant is con
nceived that deelivers energy tto the differentt buildings on
the campus.
In a first step studen
nts will list the advantages
a
and disadvantagees based on liteerature, own in
nsights resultin
ng
in a SW
WOT analysis for
f both optionss.
In a se
econd main ste
ep students will develop a mo
odel in a dynam
mic energy simu
ulation tool to a
assess the
advanttages and disadvantages for both options. This
T
model con
nsists of 3 subm
models: (1) a m
model describin
ng
the en
nergy demand for
f the building
gs, (2) a modell describing thee energy produ
uction units (he
ere distinction is
made between produ
uctions units within
w
the building and central units) and (3)) a model descrribing the
us energy distriibution grid in case
c
of the cen
ntralized system
m.
campu
In a th
hird step measu
urements on th
he existing (verry old) thermall grid are carrieed out to provid
de insight in th
he
distribution losses an
nd to evaluate the
t performancce of the modeels.
The fo
ourth step is to develop and assess
a
differentt scenarios for tthe centralized
d and decentrallized option to
and co
ome to a conclu
usion which of the systems pe
erforms best in
n terms of enerrgy demand.
In a fiffth step an eco
onomical cost-b
benefit analysiss is carried out to come to final conclusions
FIG 1. An overview of
o the Arenberg
g Campus
BWF
F-19
Ontw
werp van de stedelijke omgeving voor optiimaal wind
d- en regen
ncomfort
Desig
gn of the urba
an canopy to improve wind
d and rain co
omfort
Superv
visor(s):
Assista
ant(s):
Contacctperson(s):
Numbe
er of students:
Language of thesis:
Project link:
Study lines:
Bert Bllocken, Staf Ro
oels
Thijs Van
V den Brande
e
thijs.va
[email protected]
@bwk.kuleuven..be
1 or 2
Dutch
I
BTO
BWK, IRA
High wind
w
speed aro
ound high-rise buildings can lead to wind discomfort an
nd local amoun
nts of streamin
ng
wind-d
driven rain. Offten pedestrian
ns are confronted with thesee problems aftter the constru
uction of a ne
ew
high-riise building in an urban env
vironment. The
ese effects can
n however be predicted usin
ng wind comfo
ort
assesssment studies which
w
consist of
o combining sttatistical meteo
orological data with aerodyna
amic informatio
on
and a comfort criterio
on.
The aerodynamic in
nformation, wh
hich transformss statistical weeather data to
o local wind sspeeds and ra
ain
o two parts: th
he terrain relatted contribution
n and the desig
gn related contribution. In th
his
intensities, consists of
w investigate the design re
elated contribu
ution using a computationall fluid dynamiccs
master thesis we will
are package (O
OpenFOAM) with an additionall wind-driven raain model.
softwa
The master
m
thesis consists
c
of the selection of a case in whicch local discom
mfort due to w
wind and rain is
presen
nt. Using CFD simulations
s
thiss discomfort wiill be quantified
d and in the neext steps poten
ntial measures tto
improv
ve wind and rain comfort in th
he urban environment will bee designed and quantified.
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