What does higher velocity of gas result in during convection heat transfer?

What does higher velocity of gas result in during convection heat transfer?

• A. Decreased rate of heat transfer
• B. No effect on heat transfer
• C. Increased rate of heat transfer
• D. Random heat loss

Answer: (C)

In convection heat transfer, the velocity of a gas plays a significant role in the rate of heat transfer. When gas velocity increases, the ability of the gas to carry heat away or distribute heat becomes more efficient. This is primarily due to two factors: 1. **Enhanced mixing**: Higher gas velocity improves the circulation of air or gas, facilitating better mixing. As the gas moves faster, it is able to transport more thermal energy away from hotter surfaces, thus increasing the overall heat transfer rate. 2. **Reduced thermal boundary layer**: At higher velocities, the thermal boundary layer (the region close to the surface where heat transfer occurs) becomes thinner. The thinner boundary layer allows for more efficient conduction from the surface to the moving gas, which increases the heat transfer rate. Therefore, as the gas velocity increases, it enhances convective heat transfer, making the selected answer correct. The improved heat transfer due to increased gas velocity is crucial in various applications, such as in heating and cooling systems, where efficient thermal management is essential.

In convection heat transfer, the velocity of a gas plays a significant role in the rate of heat transfer. When gas velocity increases, the ability of the gas to carry heat away or distribute heat becomes more efficient. This is primarily due to two factors:

1. Enhanced mixing: Higher gas velocity improves the circulation of air or gas, facilitating better mixing. As the gas moves faster, it is able to transport more thermal energy away from hotter surfaces, thus increasing the overall heat transfer rate.

2. Reduced thermal boundary layer: At higher velocities, the thermal boundary layer (the region close to the surface where heat transfer occurs) becomes thinner. The thinner boundary layer allows for more efficient conduction from the surface to the moving gas, which increases the heat transfer rate.

Therefore, as the gas velocity increases, it enhances convective heat transfer, making the selected answer correct. The improved heat transfer due to increased gas velocity is crucial in various applications, such as in heating and cooling systems, where efficient thermal management is essential.