Why is higher heat transfer occurred in drop wise condensation than the film wise condensation?

Define modified latent heat of vaporization. Why is it used?

One hundred tubes of diameter 2.0 cm each are arranged in a squared array and exposed to atmospheric steam, Calculate the mass of steam condenses per unit length of tube for a tube wall temperature of 95 °C.

Differentiate between boiling and evaporation. How can boiling heat transfer be enhanced? Explain in brief.

Why is modified latent heat used? Explain also why higher heat transfer occurred in dropwise condensation than in filmwise.

Steam at 105°C at atmospheric pressure condenses on a 4m high and 3m wide vertical plate which is maintained at 80°C by circulating cooling water through one side. Determine

• the rate of heat transfer by condensation to the plate,
• the rate at which the condensate drops off the plate at the bottom.

What is the difference between film- and drop-wise condensations? Which is more effective mechanism of heat transfer? Why? How can film-wise condensation be converted into drop-wise condensation?

What is the modified latent heat of vaporization? For what is it used? How does it differ from ordinary latent heat of vaporization?

Saturated steam at atmospheric pressure condenses on a 3m high and 2m wide vertical plate which is maintained at 75°C by circulating cooling water through one side. Determine:

• the rate of heat transfer by condensation to the plate.
• the rate at which the condensate drops off the plate at the bottom.

Draw the temperature and velocity profile for condensation in a vertical plate. Why is higher heat transfer in drop wise condensation than in film wise condensation?

Why is modified latent heat of condensation used in condensation process?

Vertical plate of 60 cm × 60 cm is maintained at 95 °C (one side, other side is insulated). It is exposed to a superheated stream of temperature 105 °C at 1 atmosphere. Calculate the amount of steam condensed per hour. Also find h value at the end of the plate.

What is the difference between film and drop-wise condensation?

What is the modified latent heat of vaporization? For what is it used?

A 50 cm by 50 cm square vertical plate is maintained at 95 °C and exposed to saturated steam at 1 atm pressure. Calculate the amount of stream condensed per hour.