Document RjBp9oYdX205aLzVRqp7w7Vqn
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CHAPTER 39
1946 Guide.
Table 10. Pressure Losses in Dichlorodifluorombthane Suction Refrigerant Lines
Copper Pipe Actual O.D.
Inches
Capacity Btu per Hour
2.000 4.000 6.000 8.000 10.000 H 12.000 14,000 16.000 18.000 20.000
7.000 10.000 16.000 20.000 m 25,000
35,000 45,000 60,000 70,000
10,000 15.000 20.000 30.000 IH 40.000
50,000 60.000 80.000 100.000
30.000 40.000 50.000 60.000 70.000 m 80.000 90.000 100.000 120.000 140.000
50.000 100.000 150.000 200,000 m 250.000 300.000 350.000 400.000
Pressure Drop in Pounds per Square Inch per 100 Ft*
Refrigerant Temperature F Deg
-10 0.3 1.3 2.8 4.8 7.4 10.5 14.0
0.4 1.0 1.9 3.3 5.0 9.7 15.8
0.3 0.7 1.2 2.6 4.6 7.0 10.0
1.6 2.7 4.2 6.1 8.7
0.7 2.6 5.6 9.8 14.8
0
0.3 1.0 2.2 3.8 5.8
8.4 11.0 14.5
0.3 0.7 1.5 2.6 4.0 7.7 12.6
0.2 0.5 0.9 2.1 3.6 5.5 7.8 14.0
1.3 2.1 3.2 4.5 6.3 8.4
0.5 1.8 3.9 6.7
10.3 14.5 19.5
10
0.2 0.8 1.8 3.1 4.8
6.8 9.1 12.0 15.0
0.3 . 0.5 1.2 2.1 3.2
6.2 10.0
0.2 0.4 0.7 1.6 2.8
4.4 6.2 11.0
1.0 1.7 2.5 3.6 4.8
6.3 8.0 , 10.0
0.4 1.4 3.0 5.2
8.0 11.3 15.3 19.6
20 30 40
0.2 0.2 0.1
0.7 0.6 0.5
1.5 1.2 1.0
2.6 2.1
1.8
3.9 3.3 v 2.8
5.6 4.7 4.0
7.6 6.4 5.4
9.8 8.3
7.0
12.3 10.4
8.7 .
. 15.0 12.7 10.7
0.2 0.2 0.2
0.5
0.4 .
0.3
1.0 0.8 0.7
1.7 1.4 1.2
2.7 2.2
1.9
5.1 ' 4.3 8.4 7.0 14.8 12.2
3.6
5.9 10.2 14.0
0.2 0.1
0.1
0.3 0.3 0.2
0.6 0.5 0.4
1.3 1.1 0.9
2.3 1.9 1.6
3.5 5.0 8.7 4 13.5
2.9 4.2 7.3 11.3
2.5 3.5 6.2 9.5
0.8 0.7 0.6 1.4 1.1 0.9 2.1 1.7 1.4 2.9 2.4 2.0 3.8 3.1 2.6
4.9 4.0 . 3.3 6.2 4.9 4.1 7.6 6.1 5.0
8.6 7.0 . 9.5
0.3 0.3 0.2 1.1 0.9 0.8 2.4 2.0 1.6 4.1 3.4 2.8
6.3 5.1 4.2 9.0 7.2 6.0 12.0 9.7 7.8 15.3 12.5 10.0
50
0.1 0.4 0.9 1.5 2.3
3.3 4.5 5.8 7.2 8.9
0.1 0.3 0.6 1.0 1.6
3.0 4.9 8.6 11.7
0.1 0.2 0.4 0.8 1.4
2.1 3.0 5.2 8.2
0.5 0.8 1.2 1.7 2.2
2.8 3.5 4.2 5.9 7.9
0.2 0.7 1.4 2.4
3.6 5.0 6.7 8.5
aLength of tubing includes the average number of fittings.
ling steam on the discharge side of the jet. The total mixture then passes from the ejector into the condenser.
The slight amount of air which may be entrained in the cooled water is removed by a small secondary ejector which raises the pressure suffi ciently so that the air can be discharged to the atmosphere. A secondary condenser is then necessary to condense the steam in the secondary jet.
While a single booster of smaller than 15 tons capacity is difficult to build, steam' jet vacuum cooling units have been.built for as small as 5 to 6 tons capacity. They can readily be built for steam pressures of from 5 to 200 lb per square inch and- condenser water temperatures as high as
Refrigeration
699
Table 10. Pressure Losses in Dichlorodifluorombthane Suction Refrigerant Lines (Concluded)
Copper Pipe Actual O.D.
Inches
Capacity Btu per Hour
50.000 100.000 150.000 200.000
250.000 300.000 350.000 400,000
450.000 500,000 550,000 600.000
Pressure Drop in Pounds per Square Inch per 100 Fra
Refrigerant Temperature Deg F
-10
0
10 20 30 40 50
0.2 0.2 0.1 0.1 0.1 0.1 0.1 0.7 0.6 0.5 0.4 0.3 0.2 0.2 1.6 1.2 1.0 0.8 0.6 0.5 0.4 2.8 2.1 1.7 1.4 1.1 0.9 0.7
4.3 3.4 2.6 2.1 1.7 1.3 1.1 6.1 4.5 3.7 3.0 2.4 1.9 1.5 8.2 6.0 5.0 4.0 3.2 2.5 2.0
7.8 6.5 5.1 4.2 3.3 2.7
7.7 6.4 5.3 4.0 3.5 7.8 6.4 5.0 4.2 7.7 6.2 5.1 7.4 6.2 .
200,000
1.2 1.0 0.8 0.6 0.5 0.4 0.4
300,000
2.6 2.0 1.6 1.3 1.0 0.8 0.7
400.000
4.5 3.4 2.6 2.1 1.7 1.4 1.3'
500.000
7.3 5.4 4.1 3.3 2.7 2.2 1.9
3X 600.000
8.1 6.0 4.7 3.8 3.1 2.7
700,000 800.000 900.000
1.000.000
8.4 6.5 5.2 4.2 3.5 8.6 6.8 5.5 4.6 8.7 7.0 5.9 8.9 7.3
' 3H
300,000 400,000 500,000 600.000
700,000 800,000 900,000 1,000,000
1,100,000 1,200,000 1,300.000 1,400.000
1.2 0.9 0.7 0.6 0.5 0.4 0.3 2.0 1.6 1.3 1.0 0.8 0.7 0.6 3.2 2.5 1.9 1.6 1.3 1.0 0.9 4.6 3.6 2.8 2J2 1.8 1.5 1.3 6.4 4.9 3.8 3.0 2.5 2.0 1.7 8.7 6.4 4.9 3.9 3.2 2.5 2.2
8.2 6.2 4.9 3.9 3.2 2.7 7.7 6.1 4.9 4.0 3.3 9.4 7.3 5.8 4.8 4.0 8.7 6.9 5.6 4.8 8.0 6.6 5.6 9.3 7.6 6.4
400.000 600.000 800.000 1.000.000 1,200,000
1.400,000 1,600.000 1,800.000 2.000.000 2,200,000
1.0 0.8 0.6 0.4 0.4 2.4 1.8 1.4 1.1 0.9 4.1 3.1 2.4 2.0 1.6 6.6 4.8 3.7 3.0 2.5 10.0 7.1 5.4 4.4 3.5
10.0 7.5 5.9 4.8 10.0 7.7 6.2 10.0 * 7.9 9.7
0.3 0.3 0.7 0.6 1.3 . 1.1 2.0 1.6 2.9 2.4
3.9 3.3' 5.1 _ 4.2 6.4 5.3 7.9 6.6 9.5 7.9
aLength of tubing includes the average number of fittings.
90 F. The steam consumption in pounds per hour per ton of refrigeration increases rapidly as the booster steam pressure is lowered. For example, the lowering of the booster steam pressure from 200 to 90 lb per square inch results in an increase in steam consumption of approximately 5 per cent, whereas a further decrease in booster steam pressure to 10 lb per square inch increases the steam consumption by approximately 72 per cent oyer that required at 200 lb per square inch.
The capacity of a steam jet system is usually controlled by controlling the number of boosters in use since the unit usually has several boosters operating on the same evaporator. Usually one booster is automatically