Problems : Module 3 - Convective Heat transfer: One dimensional, Heat Transfer
Frequently Asked Questions and Problems for Practice (Module 3)
|Q.1||What is convection and how is it different than conduction?|
What is heat transfer coefficient? Explain its physical significance.
|Q.3||What is film thickness? What is its relevance in the heat transfer operations?|
|Q.4||Out of Ui and Uo, which one is larger in magnitude and why?|
|Q.5||What is the concept of controlling resistance?|
|Q.6||What is critical insulation thickness? Comment on the critical insulation thickness of a plane wall.|
The temperature profile of a solid sphere is at steady state condition, the temperature Tis in oC and r is in meter. The thermal conductivity of the sphere is 15 W/m oC. The solid sphere is put in the atmosphere condition at 30 oC. Calculate the rate of heat transfer and evaluate the maximum temperature in the sphere?
Steam at 170 oC is flowing in a 10 cm diameter pipe. In order to reduce the heat loss to the environment (at 30 oC) the pipe is planned to be insulated with 10 cm thick insulator. The various data is given under
Estimate the pay-back period assuming a rate of interest of 0.18/yr.