Test: Heat Transfer - 5 - Chemical Engineering MCQ

The Fourier number (defined as a.t/L²) is used in the analysis of problem involving heat transfer by

The energy radiated from a surface Q at absolute temperature T is related as

Baffles are provided in heat exchangers to increase the

In case of a vertical tube evaporator, with increase in the liquor level, the

The ratio of total radiating power to the absorptivity of the body depends upon the __________ as per Kirchoffs law.

200 kg of solids (on dry basis) is subjected to a drying process for a period of 5000 seconds. The drying occurs in the constant rate period with the drying rate as, Nc = 0.5 x 10-3 kg/m2.s. The initial moisture content of the solid is 0.2 kg moistu

For gases, the thermal conductivity increases with temperature rise. For liquids, with increase in concentration, its thermal conductivity generally

In a liquid-liquid heat exchanger, for the same process temperature, the ratio of the LMTD in parallel flow to the LMTD in counter flow is always

A 2-4 heat exchanger involves

Which of the following forced convection heat transfer equation accounts for the liquid viscosity effect for viscous liquids ?

With increase in temperature, the thermal conductivity of steel

The main function of baffles provided in a shell and tube heat exchanger is to

In a single effect evaporator, the economy is

Latent heat absorbed by 1 lb of water at 212^oF, when it is changed to steam at 212^oF, may be around __________ BTU.

LMTD correction factor which is to be applied for a cross-flow heat exchanger increases with increase in the number of shell passes. Its value for a single pass cross flow heat exchanger is

Which of the following is not concerned with the heat transfer?

In counter flow compared to parallel flow,

The thermal radiative flux from a surface of emissivity = 0.4 is 22.68 kW/m². The approximate surface temperature (K) is
(Stefan-Boltzman constant = 5.67xl0^-8 W/m².K⁴)

Crystallisation of solids from a homogeneous solution is a/an __________ process.

A multiple effect evaporator has a capacity to process 4000 kg of solid caustic soda per day, when it is concentrating from 10% to 25% solids. The water evaporated in kg per day is

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

Value of Prandtl number for water ranges from