Document 67rnkDB7QX0Oq29q5p3Ryw1E
American Society of Heating and Ventilating Engineers Guide, 1936.
Temperature Deg F
0 10 20 30 40 SO 60 70 80 90 100 110 120 130 140 150 160 180 200 220 240 260 280 300 350 400 450 500 550 600 700 800 . . 900. 1000
Table 1. Properties of Dry Air* Barometric Pressure 29.921 In.
CuWeight per
Ft
Pounds
0.08636 0.08453 0.08276 0.08107 0.07945 0.07788 0.07640 0.07495 0.07356 0.07222 0.07093 0.06968 0.06848 0.06732 0.06620 0.06510 0.06406 0.06205 0.06018 0.05840 0.05673 0.05516 0.05367 0.05225 0.04903 0.04618 0.04368 0.04138 0.03932 0.03746 0.03423 0.03151 0.02920 0.02720
Per Cent op Volume
at 70 F
. Btu Absorbed bt One Cu Ft Dar Air
per Deg F
0.8680
0.02080
0.8867
0.02039
0.9057
0.01998
0.9246
0.01957
0.9434
0.01919
0.9624
0.01881
0.9811
0.01846
1.0000
0.01812
1.0190
0.01779
1.0380
0.01747
1.0570
0.01716
1.0756
0.01687
1.0945
0.01659
1.1133
0:01631
1.1320
0.01605
1.1512
` 0.01578
1.1700
0.01554
1.2080
0.01506 .
1.2455
0.01462
1.2833
0.01419
1.3212
0.01380
1.3590
0.01343
1.3967
0.01308
1.4345
O.Oi274
1.5288 ' li6230 1.7177 1.8113 1.9060 ' 2.0010 2.1900 : 2.3785 2.5670 , . 2.7560
0.01197 0.01130 0.01070 0.01018 0.00967 0.00923 0.00847 0.00782 0,00728 0.00680
Cu Ft Dbt Am
Warmed One Degree per Btu
48.08 49.05 50.05 51.10 52.11 53.17 54.18 55.19 56.21 57.25 . 58.28 59.28 60.28 61.32 62.31 63.37 64.35 , 66.40 68.41 70.48 72.46 74.46 76.46 . 78.50 83.55 88.50 93.46 98.24 103.42 108.35 118.07 127.88 137.37 . 147.07 .
From Fan Engineering
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Chapter 1--Fundamentals of Heating and Air Conditioning
It is usual to assume that dry air, moist air, and the water vapor in the air follow the laws of perfect gases. This assumption while not absolutely true, especially with saturated vapor at temperatures much above 140 F,
Table 2. Properties of Saturated AiRa Weights of Air, Vapor of Water, and Saturated Mixture of Air and Vapor at 29.921 Inches of Mercury
Temp.
FDeg
Weight in a Cubic Foot op Mixture
Btu Absorbed bt Cubic Feet Sat.
One Cubic Foot Air Warmed One
Weight or
Dbt Am
Weight op Vapor
Total Weight op the Mixture
Sat. Air per Deg F
Degree per Btu
Pounds
Pounds %
Pounds
Specific
per. Pound op Mixturb
0 10 20 30 40 50 60 70 80 90 100 110 120 ; 130 140 150 160 170 . 180 190 200 210 ` 212
0.08625 0.08433 0.08246 0.08062 0.07878 0.07694 0.07506. 0.07310 0.07103 0.06879 0.06635 0.06364 0.06060 0.05715 0,05319 0.04864 0.04340 0.03734 0.03035 0.02228 .0.01300 0.00230 0.00000
0.000068 0.000110 0.000176 0.000277 0.000409 0.000587 0.000828 0.001151 0.001578 0.002134 0.002850 0.003762 . 0.004914. 0.006351 0.008120 0.010295 O'012936 0.016108 0.019896 0.024400 0.029715 0.035938 0.037307
0.08632 0.08444 0.08264 0.08090 0.07919 0.07753 0.07589 0.07425 0.07261 0.07092 0.06920 0.06740 0.06551 0.06350 0.06131 0.05894 0.05634 0.05345 0.05025 0.04668 0.04272 0.03824 0.03731
0.02083 0.02039 0.01998 0.01958 0.01921 0.01885 0.01851 0.01819 0.01790 0.01762 0.01736 0.01714 0.01695 0.01679 0.01668 0.01662 0.01662 0.01668 0.01684 0.01710 0.01749 0.01802 0.01815
48.02 49.05 50.07 51.07: 52.06 53.05 54.02 54.97 55.87 56.76 57.59 58.35 . 59.00 59.56. 59.96 ' 60.17 60.17 59.96 59.38 58.49 57.18 55.50 55.10
0.2413 0.2415 0.2418 0.2420 0.2426 0.2431 0.2439 0.2450 0.2465 0.2485 0.2509 0.2543 0.2587 0.2644 0.2721 0.2820 0.2950 0.3121 0.3351 0.3663 .0.4094 0.4712 0.4865
From Fan Engineering.
is sufficiently accurate for practical purposes and it greatly simplifies computations.
Boyle's Law refers to the relation between the pressure and volume of a gas, and may be stated as follows: With temperature constant, the volume of a given weight of gas varies inversely as its absolute pressure. ' Hence, if Pi and Pi represent the initial and final absolute pressures, and V\ and Vt represent corresponding volumes of the same mass, say one pound of
gas, then---^ = --2, or Pi Vi = Pi Vi, but since Pi Vi for any given case is Vi Pi
a definite constant quantity, it follows that the product of the absolute
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