00000ME467121907 Pages: 2

Reg No.: Name:
APJ ABDUL KALAM TECHNOLOGICAL UNIVERSITY

Seventh semester B.Tech examinations (S), September 2020

Course Code: ME467
Course Name: Cryogenic Engineering
Max. Marks: 100 Duration: 3 Hours
PARTA
Answer any three full questions, each carries 10 marks. Marks

1 ७) Differentiate Type I and Type II superconductors mentioning their applications. (2)
b) Give boiling point of following liquids a) Nitrogen b) Oxygen c) Hydrogen (3)

d) Helium e) Neon f) Argon.
€) Describe in detail the variation of mechanical properties of various materials at (5)

cryogenic temperatures.

2 93) Explain two applications of superconductivity. (2)
b) Explain Meissner effect and mention its significance? (3)
c) Explain the application of cryogenics in the field of electronics. (5)
3 a) Explain Joule Thomson coefficient. Mention its significance. (4)

b) Compare Claude Liquefaction system and Linde Hampson Liquefaction (6)

system.
4 a) Explain the advantages and limitations of pre cooled Linde Hampson cycle? (4)
b) Explain the working of Stirling cryocoolers with the help of neat diagrams. (6)

PART छ
Answer any three full questions, each carries 10 marks.
5 9) Explain the limitations of Simple Linde-Hampson cycle which makes it (4)
inefficient for the liquefaction of Neon, Hydrogen and Helium.
b) With sketches, explain the different critical components present in gas (6)

liquefaction systems.

6 ಖ Explain the significance of thermal valves in cryogenic refrigeration systems. (3)
b) With the help of a T-s diagram explain working of a Simon Helium liquefier. (7)
7 ஐ Explain thermodynamically ideal isobaric source refrigeration system. (4)

b) Explain the working of a Vuilleumier refrigerator. Derive an expression for (6)

COP of a Vuilleumier refrigerator.

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