P13621: Heat Transfer Lab Equipment
Website: https://edge.rit.edu/edge/P13621/public/Home
Mission Statement:
Provide students with the ability to observe conductive heat transfer and the ability to
measure the thermal conductivity of a material.
Project Background:
The transfer of heat through a material in any state is the process of heat transfer.
Conductive heat transfer through a solid has been done for years in industry to heat or
cool materials. It also happens everywhere around us. A material’s ability to transfer
heat is a measurable quantity called thermal conductivity.
Objectives/ Scope:
1. Develop apparatus for students to observe conductive heat transfer and measure
thermal conductivities of various samples
2. Ability for students to compare experimental results to published thermal
conductivities
3. Obtain data from manual measurement and DAQs
4. Visually demonstrate conductive heat transfer
5. Allow students to observe steady state heat transfer conditions
With a 50/50 mix of water
and glycol, the cooling loop
can provide a constant low
temperature boundary without
the complications of freezing.
Fourier’s Law
Qdot = -K ∇ T
One Dimensional
Temperature Gradient
Heat Flux over constant area
Qdot = Q / A
∇ T = ∆T / ∆x
Change in
Temperature
∆T = T1 – T2
Change in
Length
∆x = L
∇ T = (T1 – T2) / L
The DAQ display allows for real
time tracking of the temperature.
This in turn enables the user to
determine when the sample has
reached steady state.
Q = K (T2 - T1) A / L
Applying relevant assumptions and simplification, Fourier’s Law may be
expressed in this form which is convenient for one dimensional analysis.
Testing Results:
Concept Selection:
Specimen
Material
Experimental K
(W/m*K)
Published K
(W/m*K)
Accuracy (%)
Aluminum
214.4
215
99.7
Brass
123.4
109
88.0
Rolled Steel
59.6
54
90.1
1. Cartridge heater in the copper heating block to heat horizontal specimen.
Insulation along length of specimen and free convection to cool the
opposite end of the specimen.
2. Hot plate used to the specimen. Cooling unit that cycles coolant used to
cool opposite end of specimen.
3. Insulated hot plate heating two samples. One is for data collection and one
is for visual display. Cooling plate absorbs heat on the opposite end.
Clamp is used to apply constant pressure.
Stainless Steel
19.6
16
82.0
Final Concept:
Aspects of each of the three conceptual designs
were chosen for the final design. Constant pressure is needed to apply
constant heat flux. The cooling unit is needed to maintain steady state
conditions. The cartridge heater is a cost-effective way to apply heat. To keep
analysis simple for laboratory students, one-dimensional, steady state heat
conduction is assumed and losses from convection and radiation are
neglected.
Top view of apparatus. Wing nuts are
used to tighten system and apply
pressure for better transfer of heat.
Tubing coming out of the cold plate
connects to the cooling unit to cool the
top of the specimen.
This plot shows that the change in temperature
against the change in distance provides a line
which represents the thermal conductive resistance
coefficient. The line should result in a linear
configuration.
Bottom view of apparatus. Dinrail is
used to guide wires from the cartridge
heater. The yellow, rubber feet are to
stabilize the apparatus on the cart.
Model of final
concept
Lab experiment: Fourier’s Law
𝑄 = −𝐾𝛻𝑇
𝑄=Qdot=heat flux
Q=heat entering system
K=thermal conductivity
A=cross-sectional area
T=temperature
Δx=L=distance between sample points
This apparatus allows the user to actively test out Fourier’s law by testing the Kvalue of the sample inserted within it. A temperature gradient is achieved by
activating the cooling loop chilling the cold plate on top while connecting the
power supply to the cartridge heater below. A copper heating block allows for a
more uniform temperature distribution. Measuring the samples height will return
the change in distance thus completing the temperature gradient. This is also
when the cross-sectional area should be taken so that one may calculate the heat
flux along with a three point backward Taylor Series Expansion and the known
value of K for the copper heating block.
With this information, one can find the experimental K value once it has reached
a steady state and compare it to tabulated results.
Heat transfer
model using
ANSYS. This
model accounts
for heat losses
due to
convection.
From Left to Right: Shannon McCormick (ChemE), Emeka
Iheme (ChemE), Jordan Hill (EE), Rushil Rane (ISE), Shayne
Barry (ME), Piotr Radziszowski (ME), Tatiana Stein (ChemE)
Acknowledgements:
Neal Eckhaus (Guide)
Steve Possanza (Guide)
Dr. Karuna Koppula (Customer)
Paul Gregoriuosa (Customer)