Heat Transfer MCQ Questions & Answers | Chemical Engineering

Critical value of the __________ number governs the transition from laminar to turbulent flow in free convection heat transfer.

In a laboratory test run, the rate of drying was found to be 0.5 × 10^-3 kg/m².s, when the moisture content reduced from 0.4 to 0.1 on dry basis. The critical moisture content of the material is 0.08 on a dry basis. A tray dryer is used to dry 100 kg (dry basis) of the same material under identical conditions. The surface area of the material is 0.04 m²/kg of dry solid. The time required (in seconds) to reduce the moisture content of the solids from 0.3 to 0.2 (dry basis) is

In pipe flow, heat is transferred from hot wall to the liquid by

Heat transfer in the laminar sublayer in case of a liquid flowing through a pipe, is mostly by

In a cooling tower, water becomes cool by

Steam side heat transfer co-efficient in an evaporator is in the range of __________ kcal/hr.m²°C.

LMTD for counterflow and prallel flow heat exchanger will be the same, when the

In a shell and tube heat exchanger, floating head is used for

What is the steam economy in case of a single effect evaporator system?

Graetz number is given by