1. How does forced convection differ from natural convection? 2. We often turn the fan on in summer to help us cool. Explain how a fan makes us feel cooler in the summer. Also explain why some people use ceiling fans also in winter.
1. How does forced convection differ from natural convection?
2. We often turn the fan on in summer to help us cool. Explain how a fan makes us feel cooler in the summer. Also explain why some people use ceiling fans also in winter.
1. Forced convection is a convective mode of heat transfer in which an external source such as a fan or blower is used to increase the heat transfer coefficient of the working fluid.
Natural convection, on the other end, is a commonly occurring convective mode of heat transfer in which the heat transfer rate depends on mother nature and cannot be altered on our will.
As a fan or blower is introduced in a region executing natural convection, the convective heat transfer coefficient is increased. Hence the heat convected increases proportionally. A boiler with a set of induced and forced draught fans is approximated to be having a heat transfer coefficient of about 50,000 W/m2K.
The inclusion of an external source for increasing heat transfer makes a natural convection an example of forced convection.
Step by step
Solved in 2 steps
