The role of simulation tools in
design process
Teet Tark
Hevac OÜ
Chairman of the Board
Calculations Drawings
HVAC-
-Architecture
Calculations Drawings Calculations Drawings
Structure – Electrics
Building Information Model
1800…1980
1970…1995
1990…2010
2000…
2100…
• Probably none of us can imagine how to
design the building without the use of
computers and specialized software
• Are there many Engineers and Architects
nowadays, who would be able to design the
building without the use of computers?
What shouldn't be forgotten and
what should be considered
• Does the person performing the simulation actually knows the logics and
principles of the particular software, its default values and how reliable
are the results?
• The person performing the simulation should have the fundamental
knowledge in this field.
• The simulation software should not be a “black box” where the user only
enters the initial data and after a while gets the results. The user has to
understand what is the reason for particular simulation outcome, what
influences the results?
• Among the designers, one quite common answer to the question “How
did you get this value?” is “This was calculated in XXX software.”
However, if someone doubts in the calculation results due to them not
being realistic, then those who performed the calculation defend their
position believing that the calculation is right, because the results was
obtained thanks to simulation software.
Simulation results depend on the
performer, his skills, approach etc.
-20,6 %
-33,6 %
Results
interpretation
EPV
120.0
100.8
96.6
EPV, kWh/(m2.a)
100.0
1,04 times
80.0
60.0
40.0
20.0
0.0
XXX
YYY
Design Company
0,6 times
Component of EPV, kWh/(m2.a)
20.0
18.0
16.0
14.0
6.1
12.0
10.1
10.0
Cooling electricity
8.0
6.0
Space heating
11.6
4.0
5.7
2.0
0.0
XXX
YYY
Design Company
2 times
How reliable are the results obtained
with the simulation software ?
Measured room temperature
Cooling load, W
How reliable are the results obtained
with the simulation software ?
2500
2000
2100
1670
1500
1000
500
0
Design
Examination
Designer’s simulation software:
• Depending on the simulation model location (including Tallinn), the software applied
solar radiation reduction coefficient (clearness of sky) 0.75.
• The cooling load design considered the calculation at the date set to the most sunny
day and the duration of sunny period was 2 days. Though, in real environment the
duration of the sunny period is significantly longer, the building structure manages to
warm up more than expected and this produces a higher cooling load.
The software manual had no information about the settings described above. Therefore,
the designer could not even know that.
The cost of the additional cooling equipment was ca 50 000 €.
Insurance refused to compensate the damage.
SOFTWARE LICENSE AGREEMENT
The software company is never liable
for anything: read the license
agreement
The results of the calculations for the building being
designed depending on the software being used
Net energy consumption, kWh/(m2*a)
60
50
40
BV2
IDA-ICE
30
Riuska
Bsim
VIP Energy
20
10
0
Space heating
Space cooling
Source: H. Voll, T. Tark 2010. Energiatõhususe miinimumnõuete tõendamise ja selle kontrolli võimekuse tõstmine
BIM
Building Information Modelling
The "I" is commonly forgotten
I
A common understanding of BIM
purpose is:
• 3D visualisation
• Structure and HVAC interference
check
• Structure voids/openings position
evaluation
• Equipment and materials
quantification/schedules
Discipline specific software
interoperability
Building refurbishment
• Integrated B
I M application is rather problematic
– The digital surveying may produce only the 3D model of
the visible parts
– In example, there is no information about wall
construction:
• What are the wall layer materials?
• Where are the reinforcement bars located?
• Where are lintels located?
– Building services designer cant do much with the visual
information, he is more interested, for example, in:
• Equipment parameters, materials, mark of equipment, what is
inside the electrical panel, control and automation etc.
Summary
•
•
•
•
•
•
The increase of the calculations accuracy
Acceleration of the design process
Evaluation of various design performance
Design optimization
Results visualization
The person performing the simulation should have the
fundamental knowledge in this field
• The simulation software should not be a “black box”
• The risks should be assessed, the responsibility should
be considered