Question

A flat plate, 0.5 m² in area, is heated at the rate of 214 W from the bottom. The upper surface is exposed to air at 23.7ºC and the surrounding wall temperature is 13.9ºC. If the temperature of the upper surface is measured to be 50.4ºC, determine the convection heat transfer coefficient between the upper surface and air. Assume the emissivity of the upper surface is 0.92.

Answer 1

To determine the convection heat transfer coefficient between the upper surface and air, use the formula q = h * A * (Ts - Tw).

Step-by-step explanation:

In order to determine the convection heat transfer coefficient between the upper surface and air, we can use the formula: q = h * A * (Ts - Tw).

Where:

• q is the rate of heat transfer (given as 214W)
• h is the convection heat transfer coefficient (to be determined)
• A is the area of the upper surface (given as 0.5m²)
• Ts is the temperature of the upper surface (given as 50.4ºC)
• Tw is the temperature of the surrounding wall (given as 13.9ºC)

Substituting the given values into the formula, we can solve for h.

214W = h * 0.5m² * (50.4ºC - 13.9ºC)

h = 214W / (0.5m² * 36.5ºC)

h = 11.72 W/(m²·ºC)