- (A) Peclet
- (B) Prandtl
- (C) Stanton
- (D) Nusselt
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- (A) With change in temperature, the radiant energy emitted by a black body remains unchanged
- (B) Absorptivity of a body approaches unity in case of diffuse reflection
- (C) Absorptivity of a perfectly black body is unity
- (D) Value of Stefan-Boltzmann constant is 4.876 × 10-8 KCal/m2.hr.°K4
- (A) The condensing film co-efficient is about 3 times lower for vertical condenser as compared to the equivalent horizontal condenser for identical situation
- (B) Film co-efficient for vaporisation decreases as a result of vapor binding
- (C) In industrial practice, sub-cooling of condensate is required, when the condensate is a volatile liquid and is to be transferred for storage
- (D) Overall heat transfer co-efficient in a heat exchanger is controlled by the value of the film coefficient, which is higher
- (A) The controlling resistance in case of heating of air by condensing steam is in the air fil
- (B) The log mean temperature difference (LMTD) for counter flow and parallel flow can be theoretically same when any one of the fluids (hot or cold fluid) passes through the heat exchanger at constant temperature
- (C) In case of a 1 – 2 shell and tube heat exchanger, the LMT
- (D) correction factor value increases sharply, when a temperature cross occurs
- (A) Orifice baffles are never used in a shell and tube heat exchanger
- (B) Pressure drop on the shell side of a heat exchanger depends upon tube pitch also
- (C) In a horizontal tube evaporator, surface blanketing by air is avoided
- (D) Split ring type and pull through type floating heads are two commonly used floating heads is heat exchangers
- (A) Reciprocal of the resistance to heat flow is called thermal conductance
- (B) Unit of thermal conductance is W/°K
- (C) Thermal conductance of a wall of thickness ‘L’, thermal conductivity ‘k’ and heat flow area ‘A’ is kL/A
- (D) None of these
- (A) Swenson-Walker crystalliser is a batch crystalliser
- (B) Super saturation of the solution is the driving potential for a crystal growth
- (C) The liquor left after the removal of crystals from a solution is called mother liquor
- (D) The first stage of crystal formation is called nucleation
- (A) Heat transfer by radiation cannot occur across an absolute volume
- (B) In case of a shell and tube heat exchanger, the pressure drop through the shell is proportional to the number of times the fluid crosses the bundle between baffles
- (C) Propagation velocity for travel of heat radiation through vacuum is equal to the velocity of the light
- (D) The amount of heat involved in the condensation or vaporisation of 1 kg of a fluid is the same
- (A) Rate = Driving force × Resistance
- (B) Driving force = Rate × Resistance
- (C) Resistance = Driving force × Rate
- (D) Rate = Resistance/Driving force
- (A) Superheated steam is preferably not used for process heating because of its low heat transfer film co-efficient
- (B) In a shell and tube heat exchanger, the shell pressure drop is maximum for orifice baffles
- (C) S.I. unit of fouling factor is Watt/m2.°K
- (D) Longitudinal fins are used in extended surface heat exchangers, when the direction of fluid flow is parallel to the axis of the tube
