Homework Help is Here – Start Your Trial Now!
Engineering
Mechanical Engineering
During a performance test of an insulation wall, a 2 m longx3-m wide portion of the wall is placed in a wind tunnel. The wall is made of 1.2 cm thick siding, 20 cm thick brick, and 1 cm thick plaster layers. The test holds one side of the wall surface (the plaster surface) constant at 20°C as shown in the figure. During the test, air is flown parallel to the 2-m side of the wall over the other side (i.e., over the siding) of the wall. The air temperature is -15°C. The free-stream velocity of air is 5 m/s. Assume a film temperature of -10°C for air. Find out the rate of heat loss through the wall (i.e., from the right most surface in the figure to air on the left) during the test. Justify if the assumed value of film temperature is reasonable. The thermal conductivity of the siding, brick, and plaster are, respectively, 0.09 W/m-K, 0.7 W/m-K, and 0.82 W/m-K. Neglect radiation effects.

During a performance test of an insulation wall, a 2 m longx3-m wide portion of the wall is placed in a wind tunnel. The wall is made of 1.2 cm thick siding, 20 cm thick brick, and 1 cm thick plaster layers. The test holds one side of the wall surface (the plaster surface) constant at 20°C as shown in the figure. During the test, air is flown parallel to the 2-m side of the wall over the other side (i.e., over the siding) of the wall. The air temperature is -15°C. The free-stream velocity of air is 5 m/s. Assume a film temperature of -10°C for air. Find out the rate of heat loss through the wall (i.e., from the right most surface in the figure to air on the left) during the test. Justify if the assumed value of film temperature is reasonable. The thermal conductivity of the siding, brick, and plaster are, respectively, 0.09 W/m-K, 0.7 W/m-K, and 0.82 W/m-K. Neglect radiation effects.

icon
Related questions
Question

answer=correct

During a performance test of an insulation wall, a 2 m long×3-m wide portion of the wall is placed in a wind tunnel. The wall is made of 1.2 cm thick siding, 20 cm thick brick, and 1 cm thick plaster layers. The test holds one side of the wall surface (the plaster surface) constant at 20°C as shown in the figure. During the test, air is flown parallel to the 2-m side of the wall over the other side (i.e., over the siding) of the wall. The air temperature is -15°C. The free-stream velocity of air is 5 m/s. Assume a film temperature of -10°C for air. Find out the rate of heat loss through the wall (i.e., from the rightmost surface in the figure to air on the left) during the test. Justify if the assumed value of film temperature is reasonable. The thermal conductivity of the siding, brick, and plaster are, respectively, 0.09 W/m-K, 0.7 W/m-K, and 0.82 W/m.K. Neglect radiation effects. 403 W - 15 °C Cold air flow ↓ Wind- tunnel side Siding Brick Plaster 8 Inside, kept at constant temp
Transcribed Image Text:During a performance test of an insulation wall, a 2 m long×3-m wide portion of the wall is placed in a wind tunnel. The wall is made of 1.2 cm thick siding, 20 cm thick brick, and 1 cm thick plaster layers. The test holds one side of the wall surface (the plaster surface) constant at 20°C as shown in the figure. During the test, air is flown parallel to the 2-m side of the wall over the other side (i.e., over the siding) of the wall. The air temperature is -15°C. The free-stream velocity of air is 5 m/s. Assume a film temperature of -10°C for air. Find out the rate of heat loss through the wall (i.e., from the rightmost surface in the figure to air on the left) during the test. Justify if the assumed value of film temperature is reasonable. The thermal conductivity of the siding, brick, and plaster are, respectively, 0.09 W/m-K, 0.7 W/m-K, and 0.82 W/m.K. Neglect radiation effects. 403 W - 15 °C Cold air flow ↓ Wind- tunnel side Siding Brick Plaster 8 Inside, kept at constant temp
Expert Solution
steps

Step by step

Solved in 4 steps with 4 images

SEE SOLUTIONCheck out a sample Q&A here
Blurred answer
Knowledge Booster
Convection
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, mechanical-engineering and related others by exploring similar questions and additional content below.