ELECTIVE –II (REFRIGERATION AND AIR CONDITIONING)
MGM’s POLYTECHNIC
DEPARTMENT OF MECHANICAL ENGINEERING
NAME OF SUBJECT – ELECTIVE II (RAC)
CLASS – THIRD YEAR
COURSE CODE - ME6E
SEMESTER – VI
1.
State and explain the unit of refrigeration.
2.
State various applications of refrigeration.
3.
What is principle of refrigeration?
4.
Name the different methods of refrigeration.
5.
What are applications of ice refrigeration?
6.
What is heat pump? Give its COP.
7.
What is ice refrigeration?
8.
Explain the Ton of refrigeration.
9.
Explain in brief steam jet refrigeration.
10.
Explain with neat sketch Vortex tube refrigeration.
11.
State advantages of Vortex tube.
12.
Explain in brief Pulse tube refrigeration.
13.
State non conventional methods of refrigeration.
14.
Show Carnot cycle on PV and TS diagram.
15.
State equation of COP of Carnot refrigerator and derive it.
16.
Show Bell Coleman cycle on PV diagram. And state COP of refrigerator.
17.
Give construction and working of Bell Coleman cycle.
18.
Show how Bell Coleman cycle is used for aircraft cooling.
19.
State advantages of Air refrigeration cycle.
20.
Show that COP of Bell Coleman cycle is less than COP of Carnot refrigerator.
MECHANICAL ENGINEERING THIRD YEAR -2013-2014
Page 1
ELECTIVE –II (REFRIGERATION AND AIR CONDITIONING)
21.
Give methods used for aircraft refrigeration.
22.
Give construction and working of Vapour compression cycle.
23.
Show Vapour compression cycle on PH and TS chart.
24.
What is sub cooling. Explain in brief with the help of PH and TS diagram.
25.
What is superheating. Explain in brief with the help of PH and TS diagram.
26.
Give application of vapour compression cycle.
27.
What is multistaging in vapour compression cycle.
28.
State need of multistage compressor in vapour compression cycle.
29.
State advantages of multistage vapour compression cycle.
30.
What is effect of variation of suction pressure in vapour compression cycle.
31.
What is effect variation of discharge pressure in vapour compression cycle.
32.
Explain in brief actual vapour compression cycle.
33.
Explain in brief two stage compression with liquid intercooler.
34.
Draw block diagram of two stage compression with water intercooler and liquid sub
cooler.
35.
What is vapour absorption refrigeration? How it differs from vapour compression
cycle.
36.
Draw block diagram of vapour absorption cycle.
37.
Explain with neat sketch practical vapour absorption cycle.
38.
Draw block diagram of lithium bromide water cooler.
39.
State advantages of vapour absorption cycle.
40.
Distinguish between vapour compression and vapour absorption cycle.
41.
State desirable properties of absorbent used in vapour absorption cycle.
42.
What is refrigerant? Give its classification.
43.
What are the properties of ideal refrigerants?
44.
State the refrigerant used for (1) ice plant (2) Domestic refrigerator.
45.
Give desirable properties of refrigerant.
MECHANICAL ENGINEERING THIRD YEAR -2013-2014
Page 2
ELECTIVE –II (REFRIGERATION AND AIR CONDITIONING)
46.
State the advantages of air used as refrigerant.
47.
What is importance of specific volume of refrigerant?
48.
Name commonly used refrigerants in refrigeration and air conditioning system.
49.
What is eco-friendly refrigerant? Name it.
50.
What is designation of refrigerant?
51.
What are properties of ammonia as refrigerant?
52.
Name different physical properties of refrigerant.
53.
What is azeotropes?
54.
“A completely odour place refrigerant is not desirable” discuss.
55.
Explain in brief how refrigerants are classified.
56.
Discuss thermodynamic properties required for good refrigerant.
57.
What are safe working properties of refrigerant?
58.
What are secondary refrigerants? Explain in brief.
59.
How primary refrigerants are classified?
60.
What is Concept of Green house?
61.
Give significance of ozone layer.
62.
What are the criteria used for selection of refrigerant for particular application?
63.
Why ozone layer is depleting? What is its effect?
64.
Classify the Compressors used in refrigeration system.
65.
Classify the evaporators used in refrigeration system.
66.
State the purpose of compressor used in refrigeration system.
67.
Classify the expansion devices used in refrigeration system.
68.
State the function of expansion device used in refrigeration system.
69.
What is rotary compressor? State its advantages.
70.
Enlist advantages of rotary compressor over reciprocating compressor.
71.
What is the function of condenser in refrigeration system? Enlist different types of
condenser.
MECHANICAL ENGINEERING THIRD YEAR -2013-2014
Page 3
ELECTIVE –II (REFRIGERATION AND AIR CONDITIONING)
72.
Explain with neat sketch plate type evaporator.
73.
Explain chillers in brief.
74.
What is finned type evaporation? Give its application.
75.
Name components of refrigeration control system.
76.
What is function of thermostat? What are their different types?
77.
Classify evaporators used in refrigeration? Describe any one in short.
78.
What is hermetically sealed compressor?
79.
What are advantages of hermetically sealed compressor?
80.
What is screw compressor?
81.
Explain with neat sketch dry expansion type evaporator.
82.
Explain with neat sketch flooded evaporator.
83.
Write short note on Capacity of evaporator.
84.
Distinguish between air cooled and water cooled condenser.
85.
What are advantages and disadvantages of capillary tube?
86.
Sketch and explain the working of automatic expansion valve.
87.
Give the classification of compressors. Explain the construction and working of
reciprocating compressor.
88.
Distinguish between open type compressor and hermetically sealed compressor.
89.
Explain with neat sketch centrifugal compressor.
90.
Explain with neat sketch thermostatic expansion valve.
91.
Define air conditioning and state factors for human comfort.
92.
State the factors that determine the human comfort.
93.
State the role of air conditioning in industries. Give two examples.
94.
What are the various applications of air conditioning?
95.
Define Dry bulb temperature.
96.
Define Wet bulb temperature.
97.
Define Wet bulb depression.
MECHANICAL ENGINEERING THIRD YEAR -2013-2014
Page 4
ELECTIVE –II (REFRIGERATION AND AIR CONDITIONING)
98.
Define Dew point temperature.
99.
Define Moist air.
100.
Define Specific humidity.
101.
Define Relative humidity.
102.
Define Absolute humidity.
103.
Define Degree of saturation.
104.
Show on psychrometric chart “Humidification”
105.
Show on psychrometric chart “De-humidification”.
106.
Show on psychrometric chart “Cooling with humidification”
107.
Show on psychrometric chart “Cooling with dehumidification”.
108.
Show on psychrometric chart “Sensible heating”.
109.
Show on psychrojmetric chart “Sensible cooling”.
110.
Show on psychrometric chart “latent heating”.
111.
Show on psychrometric chart “latent cooling”.
112.
What are the purposes of Air conditioning?
113.
What is Evaporative cooling?
114.
What is the use of Psychrometer?
115.
Give classification of Psychrometer.
116.
What is Psychrometric chart? State uses of it.
117.
State various psychrometric properties of air.
118.
State the difference in air conditioning system used for human comfort and industrial
purpose.
119.
State Dalton‟s law of partial pressure.
120.
State advantages of central system over unitary air conditioning system.
121.
State the advantages of unitary system over central air conditioning system.
122.
Show the “Dehumidification of moist air by cooling” on psychrometric chart.
MECHANICAL ENGINEERING THIRD YEAR -2013-2014
Page 5
ELECTIVE –II (REFRIGERATION AND AIR CONDITIONING)
123.
Show the “Cooling and humidification by evaporative cooling” on psychrometric
chart.
124.
Distinguish between comfort air conditioning and industrial air conditioning.
125.
Distinguish between comfort air conditioning and commercial air conditioning.
126.
Explain in brier sensible heating process and state by pass factor.
127.
What is evaporative cooling? Explain pad type evaporative cooler with neat sketch.
128.
Distinguish between unitary a/c and central air conditioning system.
129.
Draw psychromedtdric chart and name different lines in it.
130.
Explain in brief „cooling with adiabatic humidification‟. Also give its effectiveness
and represent process on psychrometdric chart.
131.
Write short note on cooling with dehumidification.
132.
Explain in brief „filters‟.
133.
Explain with neat sketch „dehumidifier‟.
134.
What are different sources of heat load?
135.
What is sensible heat factor?
136.
Name outdoor sources of heat load.
137.
State factors affecting human comfort.
138.
What is comfort chart.
139.
Explain in brief comfort chart.
140.
How will you calculate heat load due to radiation transmitted through glass?
141.
How human body behaves in winter season?
142.
How human body behave in winter season?
143.
What is sensible heat load and latent heat load? What are the different factors for
above?
144.
How do you calculate cooling load for restaurant? Explain in detail. How do you
calculate cooling load for restaurant? Explain in detail.
145.
For estimating the cooling load, what are the heat sources you will consider?
MECHANICAL ENGINEERING THIRD YEAR -2013-2014
Page 6
ELECTIVE –II (REFRIGERATION AND AIR CONDITIONING)
146.
Explain in brief heat load by conduction from wall.
147.
What is importance of occupant load in load calculation?
148.
Explain in brief infiltration of air.
149.
What factor you will consider for calculation of heat load of restaurant?
150.
Explain in brief importance of ventilation.
151.
How air conditioning systems are classified?
152.
Distinguish between industrial and commercial air conditioning system.
153.
Explain in brief commercial air conditioning.
154.
Distinguish between comfort and industrial air conditioning.
155.
Explain in brief industrial air conditioning.
156.
Distinguish between central and unitary air conditioning.
157.
Explain in brief central air conditioning.
158.
Explain in brief window air conditioning.
159.
Give application areas of air conditioning system.
160.
Explain with block diagram summer air conditioning system.
161.
Explain with block diagram winter air conditioning system.
162.
Explain with block diagram year round air conditioning system.
163.
Name the different elements of air distribution system.
164.
What are different outlets used in Air distribution system?
165.
State three losses in ducts, used in air distribution system.
166.
Which material is commonly used for making ducts?
167.
Give classification of ducts used in air conditioning system.
168.
Give the classification of fans and blowers.
169.
Name different types of centrifugal fans.
170.
Name different axial flow fans.
171.
Sketch and explain the perimeter loop system of air distribution system.
172.
Sketch and explain the radial perimeter system for air distribution.
MECHANICAL ENGINEERING THIRD YEAR -2013-2014
Page 7
ELECTIVE –II (REFRIGERATION AND AIR CONDITIONING)
173.
Enlist various losses in ducts.
174.
Give classification of fans used in air distribution system.
175.
Explain with neat sketch propeller fan.
176.
Explain with neat sketch tune axial fan.
177.
What are various losses in duct?
178.
What care and precaution is required to take while designing and laying duct?
179.
What is meant by thermal insulation? Name various types of insulating material.
180.
What are the types of insulating materials used in A.C. plant?
181.
Which material is commonly used for insulating ducts?
182.
List the name of Natural insulating materials.
183.
State the prosperities of ideal insulating material used for air conditioning system.
184.
What are different types of insulating materials? Write various factors to be
considered for selecting it.
185.
Explain in brief method of laying insulating.
186.
How insulating is applied on hot surface?
187.
How insulation is applied on cold surface?
Best of luck
MECHANICAL ENGINEERING THIRD YEAR -2013-2014
Page 8