The outlet temperature of cooling water in a heat exchanger is generally not allowed to exceed above 50°C in industrial practice mainly to avoid Uneconomic LMTD Its evaporation loss Excessive corrosion Decrease in heat exchanger efficiency TRUE ANSWER : ? YOUR ANSWER : ?
Film condensation is promoted on a/an __________ surface. clean & smooth oily coated dirty TRUE ANSWER : ? YOUR ANSWER : ?
In a multiple effect evaporator, the effect of boiling point elevation is to all of the listed here reduce the economy reduce the capacity increase the economy TRUE ANSWER : ? YOUR ANSWER : ?
Vent pipes are provided in a condenser to Facilitate easy cleaning of tubes Purge the condenser None of these Remove non-condensable gases TRUE ANSWER : ? YOUR ANSWER : ?
A cube, sphere & a thin circular plate (all having same mass and made of same material) are all heated to 300°C and allowed to cool in natural air. Which one will cool the slowest ? All of these Sphere Cube Plate TRUE ANSWER : ? YOUR ANSWER : ?
The unit of heat transfer co-efficient in SI unit is W/m2°K W/m°K J/M2°K J/m°K TRUE ANSWER : ? YOUR ANSWER : ?
Which of the following forced convection heat transfer equation accounts for the liquid viscosity effect for viscous liquids? None of these Dittus-Boeltier equation Sieder-Tate equation Nusselt equation TRUE ANSWER : ? YOUR ANSWER : ?
Forced circulation evaporators are useful for the concentration of viscous, salting and scale forming liquors. Which of the following is a forced circulation evaporator? Long vertical evaporator Agitated film evaporator Horizontal tube evaporator Calenderia vertical tube evaporator TRUE ANSWER : ? YOUR ANSWER : ?
Vacuum is generally maintained in the vapour space of an evaporator mainly to Achieve very high concentration of the final product Concentrate heat sensitive materials Get economical temperature difference by using moderate pressure steam Facilitate forward feeding in multiple effect evaporation TRUE ANSWER : ? YOUR ANSWER : ?
The energy radiated from a surface Q at absolute temperature T is related as Q ∝ T³ None of these Q ∝ T⁴ Q ∝ T² TRUE ANSWER : ? YOUR ANSWER : ?