Heat Transfer - Engineering

Q1:

Pick out the wrong statement.

A 'Solvates' are chemical compounds formed by solute with their solvents. When water is the solvent, then it is called a 'hydrate'.

B In heat exchanger calculations (Δt)weighted is used in place of Δt, when it involves more than one sequence of heating or cooling i.e., desuperheating & condensation or condensation & sub-cooling.

C Heat transfer co-efficient during nucleate boiling is not influenced by the agitation imparted.

D In case of short tube vertical evaporators, area of central downtake is about 50 to 100% of the total tube cross-sectional area.

ANS:C - Heat transfer co-efficient during nucleate boiling is not influenced by the agitation imparted.

The wrong statement is: "Heat transfer co-efficient during nucleate boiling is not influenced by the agitation imparted." In reality, the heat transfer coefficient during nucleate boiling is significantly influenced by the agitation imparted to the fluid. Agitation helps in enhancing nucleate boiling by promoting the movement of bubbles away from the heating surface, which can lead to better heat transfer rates. Therefore, agitation plays a crucial role in nucleate boiling heat transfer. The correct statement would be that the heat transfer coefficient during nucleate boiling is influenced by the agitation imparted.