![ According to the Fourier's law, the heat transfer rate
of the plate is proportional to the temperature
difference and the thermal conductivity , but it's
inversely proportional to the thickness of the
plate .
4.the heat transfer rate ： [W]
t
A
Q
Q
t
A
t
Q
)
/( C
m
W
](https://image.slidesharecdn.com/measurementofthermalconductivitybysteadystateplatemethod-241129004919-a2baaae7/85/Measurement-of-thermal-conductivity-by-steady-state-plate-method-pptx-8-320.jpg)
Measurement of thermal conductivity by steady state plate method .pptx
- 2. 1.Three basic modes of heat transfer?
- 3. Conduction happens when there is a temperature gradient in a solid material or a stationary fluid. Convection happens when heat transfer takes place between a surface and a flowing fluid. Radiation happens when heat is exchanged directly between two surfaces at different temperatures by electromagnitic waves.
- 4. 2.Which brick is the better for house in cold regions? Why ？ hollow brick solid brick
- 5. Answer ： The hollow brick The hollow brick is filled with air and the thermal conductivity of air is very low. The hollow brick is a good insulation material. Therefore, hollow brick should be chosen. air brick brick
- 6. Heat transfer Measurement of thermal conductivity
- 8. According to the Fourier's law, the heat transfer rate of the plate is proportional to the temperature difference and the thermal conductivity , but it's inversely proportional to the thickness of the plate . 4.the heat transfer rate ： [W] t A Q Q t A t Q ) /( C m W
- 12. t3 t1 t2 t4 Cooling water Plate1 Plate2 Heater Cooling water inlet and outlet Cooling water
- 13. 1.Test material: PV plastic plate 2.Device dimensions:300×300 mm2 3.Calculation area of heat conduction A: 200×200 mm2 4.Plate thicknessδ:20mm 5.Resistance value of heater:100Ω 6.Thermocouple material: nickel chromium, nickel silicon 7.Maximum heating temperature:≤80℃ 8.Heater voltage: 0—50V ， current: 0—4A （ Adjustable ） Main parameters
- 14. A t Q ) /( C m W 2 I U Q mm 20 2 mm 200 200 A 2 - 2 4 3 2 1 t t t t t
- 15. (1)Turn on the device . (2)The voltage knob is adjusted to 10V firstly. The T1, T2, T3, T4 and the current value can be recorded when the data are basically stable. (3) According to the step 2, the voltage will be adjusted to 15V, 20V and 25V in turn and every stable result will be recorded. Experimental Procedures
- 16. Experimental Results Processing voltage (V) current (A) t1 t2 t3 t4 10 0.99 37.4 37.3 29.8 29.6 15 1.47 45.5 45.3 32.5 32.0 20 1.95 56.3 56.2 36.3 35.0 25 2.37 67.4 67.3 39.5 37.8 t t Experiment chart 2 - 2 4 3 2 1 t t t t t 2 / ) 2 2 ( 4 2 3 1 t t t t t