Gnome Rhone Jupiter 9AD| aircraft investigation

AIRCRAFT INVESTIGATION

performance calculations for the Gnome Rhone Jupiter VI (9AD) aircraft engine

Jupiter IV 9AB

Gnome Rhone Jupiter VI (9AD) air-cooled 9 -cylinder radial engine 420 [hp](313.2 KW)

German engine rating : 425.8 [PS]

introduction : 1926 country : France importance : ***

applications : Junkers W.34

normal rating : 420 [hp](313.2 KW) at 1650 [rpm] at 0 [m] above sea level

no reduction, direct drive, valvetrain : push rot

fuel system : oil system :

weight engine(s) dry : 361.0 [kg] = 1.15 [kg/KW]

bore : 146.0 [mm] stroke : 190.5 [mm]

valve inlet area : 39.0 [cm^2] two inlet and two exhaust valves in cylinder head

gasspeed at inlet valve : 31.7 [m/s]

throttle : 91 /100 open, mixture :13.0 :1

compression ratio: 5.30 :1

stroke volume (Vs) : 28.76 [litre]

compression volume (Vc): 6.675 [litre]

total volume (Vt): 35.379 [litre]

diam. engine : 141 [cm]

engine length: 0.29 [m]

specific power : 10.9 [kW/litre]

torque : 1813 [Nm]

engine weight/volume : 12.6 : [kg/litre]

average piston speed (Cm): 10.5 [m/s]

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intake pressure at 0 [m] altitude Pi : 0.91 [kg/cm2]

mean engine pressure (M.E.P.) at 0 [m] altitude Pm : 6.52 [kg/cm2]

compression pressure at 0 [m] altitude Pc: 7.28 [kg/cm2]

estimated combustion pressure at 0 [m] Pe : 29.10 [kg/cm2]

exhaust pressure at 0 [m] Pu : 3.56 [kg/cm^2 ]

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compression-start temperature at 0 [m] Tic: 367 [°K] (94 [°C])

compression-end temperature at 0 [m] Tc: 541 [°K] (268 [°C])

average engine wall temperature at 0 [m] : 476 [K] (202 [°C])

caloric combustion temperature at 0 [m] Tec: 2186 [°K] (1913 [°C])

polytroph combustion temperature at 0 [m] Tep : 2161 [°K] (1888 [°C])

estimated combustion temperature at 0 [m] Te (T4): 2139 [°K] (1866 [°C])

polytrope expansion-end temperature at 0 [m] Tup: 1175 [°K] (902 [°C])

exhaust stroke end temperature at 0 [m] Tu: 1098 [°K] (825 [°C])

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calculations for take-off/emergency power at sea level

compression-end temperature at sealevel max rpm Tc:550 [°K] (277 [°C])

polytrope combustion temperature at sea level Tec: 2196 [°K] (1923 [°C])

emergency/take off rating at 1795 [rpm] at sea level : 450 [hp]

Gnome Rhone

Thermal efficiency Nth : 0.341 [ ]

Mechanical efficiency Nm : 0.765 [ ]

Thermo-dynamic efficiency Ntd : 0.261 [ ]

design hours : 1533 [hr] time between overhaul : 40 [hr]

dispersed engine heat by cooling air : 3781.84 [Kcal/minuut/m2]

required cooling surface : 16.67 [m2]

fuel consumption optimum mixture at 1650.00 [rpm] at 0 [m]: 100.62 [kg/hr]

specific fuel consumption thermo-dynamic : 230 [gr/epk] = 309 [gr/kwh]

estimated specific fuel consumption (cruise power) at 0 [m] optimum mixture : 309 [gr/kwh]

estimated sfc (cruise power) at 3100 [m] rich mixture : 324 [gr/kwh]

specific fuel consumption at 0 [m] at 1650 [rpm] with mixture :13.0 :1 : 321 [gr/kwh]

estimated specific oil consumption (cruise power) : 25 [gr/kwh]

Literature :

Handbook of aeronautics volume II Aero-engines page 13

DISCLAIMER Above calculations are based on published data, they must be

regarded as indication not as facts.

Calculated performance and weight may not correspond with actual weights

and performances and are assumptions for which no responsibility can be taken.

Calculations are as accurate as possible, they can be fine-tuned when more data

is available, you are welcome to give suggestions and additional information

so we can improve our program. For copyright on drawings/photographs/

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