Heat Exchanger Analysis & Design Question Paper 2014 for BPUT M.Tech 2nd Semester is given below for practice. In Previous year Question papers the questions were asked from the Heat Exchanger Part of Heat Transfer. The best book for this subject is Heat and Mass Transfer ook By Mahesh Rathode
Heat Exchanger Analysis & Design Question Paper 2014
2nd Semester Regular/Back Examination
HEAT EXCHANGER ANALYSIS & DESIGN
BRANCH(S): MECHANICAL ENGINEERING (HEAT POWER ENGINEERING)
Time: 3 Hours, Max Marks: 70
Answer Question No.1 which is compulsory and any five from the rest.
Q1 Answer the following questions:
a) What do you mean by compact heat exchanger and write the importance of Area density in it.
b) Are we really getting extra advantage by providing Baffles in Shell and tube heat exchanger Justify your answer.
c) Under what condition, the effectiveness NTU method is preferred over LMTD method as a method of analysis of Heat exchanger
d) In a liquid to gas heat exchanger, it is best to put extended surfaces on the gas side. Why?
e) What do you mean by hydraulic diameter and its impact on heat exchanger?
f) What are the heat transfer modes are involved in heat exchanger for heat transfer augmentation?
g) Write the parameters that influence fouling resistances
h) List the effect of channel divergence.
i) How can the flow induced vibration be minimized?
j) What are the causes of pressure drop in shell and tube heat exchanger?
Q2 a) How fouling is dealt while designing heat exchangers.
b) A counter-flow double-pipe heat exchanger is to heat the cold fluid from 30°C to 65°C at a rate of 2 kg/s. The heath ig is to be accomplished by hot fluid available at 100°C at a mass flow rate of 1 kg/s. The inner tube is thin-walled and has a diameter of 1.5 cm. Specific heat of the hot fluid is 10kJ/kgK and that of the cold fluid is 5 kJ /kgK. If the overall heat transfer coefficient of the heat exchanger is 640 W/m2 °C, determine the length of the heat exchanger required to achieve the desired heating.
Q3 Explain how the makeup water requirement is estimated from energy and mass balance of a cooling tower.
Q4 a) What do you mean by differential thermal expansion? Write the necessary steps are being taken to avoid this
b) Show with neat sketch of temperature distribution for unmixed cross flow heat exchanger and explain it.
Q5 a) Derive the effectiveness of counter flow heat exchanger
b) What would be the effectiveness of counter flow heat exchanger if Cmin/Cmax = 0 and Cmin/Cmax=1
Q6. The condenser of a large steam power plant is a heat exchanger in which stem is condensed to liquid water. Assume the condenser to be a shell-and-tube heat exchanger consisting of a single shell and 30,000 tubes, each executing two passes. The tubes are of thin wall construction with D=25 mm, and steam condenses on their outer surface with an associated convection coefficient of h0=11,000 W/m.K the heat transfer rate that must be effected by the exchanger is q=2×10^9 W , and this is accomplished by passing cooling water through the tubes at a rate of 3×10^4 kg/sec. the water enters at 20°C while the steam condenses at 50 degree C. What is the temperature of the cooling water emerging from the condenser? What is the required tube length L per pass?
Q7. a) What are the various sources of a noise in a heat echanger ? How it can be minimized ?
b) What are the causes of development of stress in a heat exchanger and how thermal stress can be minimized ?
Q8. Write Short Notes (Any Two)
a) Flow pattern of baffles
b) Regenerator Vs Recuperaotor
c) Turbulence and friection factor in pipe flow.