Document 240MVYRVOB1dLvwmOMN6QrNb
14
CHAPTER 2
1957 Guide
Thermal conductance per unit area, Unit conductance: heat transferred per (unit time) (unit area) (degree).................................................................. ... C
C - c_ 1 - 9 - *
* A RA A(f, - Q L
Thermal conductivity: heat transferred per (unit time) (unit area) (degree per unit length)........................................................................................... .................. k
_9 A k = (h - ti) L
Surface coefficient of heat transfer, Film coefficient of heat transfer. Individual coefficient of heat transfer: heat transferred per (unit time) (unit area) (degree)......................................................................................................................f
g A / = t,-tt (In general / is not equal to k/L, where L is the actual thickness of the fluid film.) Overall coefficient of heat transfer, Thermal transmittance per unit area: heat transferred per (unit time) (unit area) (degree overall).....................................V
A U=
U -- fi
Thermal transmission (heat transferred per unit time).............. .............................. q
Q
9=7
Thermal resistance (degree per unit of heat transferred per unit time)................. R
Thermal resistivity.......................................................................................................1/4
Vaporization values at constant pressure. Differences between values for satu
rated vapor and saturated liquid at the same pressure....................Svbscript fg
Velocity................................................................................................................... V
Viscosity, absolute......................................................
M
Viscosity, kinematic.....................................................................................................u/p
Volume (total)..............................................................................................................V Volume per unit time, Rate at which quantity of material passes through a
machine, Quantity of heat per unit time, Quantity of heat per unit weight---- q Weight of a major item. Total weight......................... ..............................................W Weight rate, Weight per unit of power, Weight per unit of time............................. w Work (total)............................. .....................................................................................IV
THE GREEK ALPHABET
Act Alpha
B0 Beta r 7 Gamma A 6 Delta E e Epsilon
Zf Zeta H,, Eta
e&e Theta
I t Iota K k Kappa A X Lambda M ja Mu NrNu
Z{ Xi 0 o Omicron n w Pi
P p Rho 2 a s Sigma T r Tau T u Upsilon 4> <p g> Phi X x Chi 'J' Psi 1 to Omega
Abbreviations, Symbols, Conversion Factors '-
CONVERSION EQUATIONS6 Heat, Power and Work
1 ton refrigeration , Latent heat of ice
1 Btu
l.Int. watthour
1 Int. kilowatthour
/ 12,000 Btu per hour \ 200 Btu per minute
143.4, Btu per pound
778.3 ft-lb 0.2930 Int. whr 252.0 I.T. calorie
2656 ft-lb 3.413 Btu 3600 Int. joules 860 I.T. calories
X Int. kilowatt (1000 watts)
lTrI'iriCal?ri?s}' A l.l. Kilocalorie/
1 horsepower
1 boiler horsepower
Weight and Volume 1 gal (U. S.)
1 British or Imperial gallon 1 cu ft
1 J
eu ft water at 60 F cu ft water at 212 F
(in
vacuo)
i eat water at 60 F 1 gal water at 212 F
r ("
")
1 lb (avdp)
X bushel 1 short ton
Pressure
1.341 hp = 56.88 Btu per minute
, 44,267 ft-lb per minute 3.968 Btu 3088 ft-lb 1.1628 Int. whr
oou rt-lb per second
cu in. / 7.481 gal ( 1728 cu in. = 62.37 lb = 59.83 lb = 8.338 lb = 7.998 lb 16 oz 7000 grains = 1.244 cu ft = 20001b
lb per square inch 1 02 per square inch
2.0360 in. mercury at 32 F 2.0422 in. mercury at 62 F 2.309 ft water at 62 F 27.71 in. water at 62 F
-{ ? v^6-in' mercury at 62 F r in. water at 62 F