Page 70 - Aeronautical Engineer Data Book

Symbols and notations 57
In the stratosphere T = T = constant so:
S
p 1 1 p
= and = RT
p 2 2
where R is the universal gas constant: R =
287.26 J/kg K
Table 3.5 shows the international standard
atmosphere (ISA). Table 3.6 shows the lesser
used US (COESA) standard atmosphere.

Table 3.5 International standard atmosphere (sea level
conditions)
Property Metric value Imperial value
Pressure (p) 101 304 Pa 2116.2 lbf/ft 2
Density ( ) 1.225 kg/m 3 0.002378 slug/ft 3
Temperature (t) 15°C or 288.2 K 59°F or 518.69°R
Speed of sound (a) 340 m/s 1116.4 ft/s
Viscosity (µ) 1.789 10 –5 3.737 10 –7
kg/m s slug/ft s
Kinematic viscosity 1.460 10 –5 1.5723 10 –4
2
2
( ) m /s ft /s
Thermal conductivity 0.0253 J/m s/K 0.01462 BTU/ft
h°F
Gas constant (R) 287.1 J/kg K 1715.7 ft
lb/slug/°R
Specific heat (C p ) 1005 J/kg K 6005 ft lb/slug/°R
Specific heat (C v ) 717.98 J/kg K 4289 ft lb/slug/°R
Ratio of specific 1.40 1.40
heats (
)
Gravitational 9.80665 m/s 2 32.174 ft/s 2
acceleration (g)