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From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Page detailing thermodynamic formulas for calculating work, charge, and scavenging in an engine cycle.

Identifier  ExFiles\Box 150\1\  scan0341
Date  28th March 1938 guessed
  
-17-

W_Ec = { 1 - (1/r)^(k-1) } x Q_c x J = work in ft. lbs. represented by area 2-3-4-5-2, where :

r = V2 / V1

k = 1.4 (=Exponent of adiabatic compression and expansion)

J = 777.7 ft. lbs. per B.t.u. (=Mechanical equivalent of heat)

R = 53.34 (Gas constant for air)

P = pressure in pounds per square inch.

V = volume in cubic feet.

W_Pc = 144 (P2 - P6) (V2 = V1) = work in foot pounds represented by area 1-2-6-7-1

W_Tc = W_Ec + W_Pc = total work in foot pounds for theoretical cycle with complete scavenging.

For "normal scavenging.

The symbols have the same significance as for complete scavenging.

M_n = 144 P2 (V2 - V8) / RT2 = weight of charge, pounds

V8 = V7 { (P7 / P8)^(1/k) } = volume of residual exhaust gas after it has been compressed to boost pressure by the incoming charge, cubic feet.

Q_n = 1000 M_n

W_En = { 1 - (1/r)^(k-1) } x Q_n x J. {Mr Johnson W.M.}

W_Pn {Mr Northey} = 144 (P2 - P6) (V2 = V1)
  
  


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