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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: - PowerPoint PPT Presentation
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Testing Results:
P13621: Heat Transfer Lab Equipment
Lab experiment: Fourier’s Law
Heat transfer model using
ANSYS. This model accounts for heat losses
due to convection.
With a 50/50 mix of water and glycol, the cooling loop can provide a constant low
temperature boundary without the complications of freezing.
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.
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
Stainless Steel 19.6 16 82.0
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)
Concept Selection: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.
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.
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
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 samples2. Ability for students to compare experimental results to published thermal
conductivities 3. Obtain data from manual measurement and DAQs4. Visually demonstrate conductive heat transfer5. Allow students to observe steady state heat transfer conditions
This apparatus allows the user to actively test out Fourier’s law by testing the K-value 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.
Fourier’s LawQdot = -K ∇ T
Heat Flux over constant areaQdot = Q / A
One Dimensional Temperature Gradient∇ T = ∆T / ∆x
Change in Length∆x = L
Change in Temperature∆T = T1 – T2
Q = K (T2 - T1) A / L
∇ T = (T1 – T2) / L
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.
Applying relevant assumptions and simplification, Fourier’s Law may be expressed in this form which is convenient for one dimensional analysis.
�̇�=−𝐾 𝛻𝑇
=Qdot=heat fluxQ=heat entering systemK=thermal conductivityA=cross-sectional areaT=temperatureΔx=L=distance between sample points