Frequently Asked Questions and Problems for Practice (Module 6)
What is Leidenfrost phenomenon?
How the presence of non-condensable gases affect the condensation rate of vapour?
What is the difference between drop-wise and film condensation?
Discuss the phenomena of condensation on a vertical and a horizontal plate.
Saturated vapour of methanol condenses on a vertical plate at 1 atm. The vertical plate is maintained at 55 oC by cooling water at the other side. Calculate the following,
Saturated steam flows in a horizontal tube having 5 cm diameter and 15 cm of length. Calculate the condensation for a tube wall temperature of 96 oC.
An uninsulated water pipe carrying water at 2 oC passes through hot and humid area where the temperature is 32 oC and the relative humidity is 75%. Estimate the condensate if the pipe is 50 mm in diameter and the exposed length is 75 cm. It may be assumed that the pipe is exposed to saturated vapour at the partial pressure of the water vapour in the air.
Compare the heat transfer coefficients for boiling water and condensing steam on a horizontal tube for normal atmospheric conditions.