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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).
Calculations for engine cooling performance, heat dissipation, and critical air temperature.

Identifier  ExFiles\Box 149a\2\  scan0263
Date  6th November 1935
  
(Appendix - Sheet 3)

Since pressure difference ∝ v^1.8 and cooling ∝ v^.8
(both very nearly)

if H₂ = cooling under car conditions
and H₁ = cooling under rig conditions,

H₂ = H₁ x { (2.580)/(2.990) * 1/1.8 }^.8 = .936 H₁

∴ Actual dissipation figure for car using 84.m.m. Mark V matrix = 66.5 x .936
= 62.2 B.T.U's/min/°C. temp. diff. between inlet water and inlet air.

∴ As before H/Δt = (602 x 62.2) / (144 x 2) = 130.0

∴ Δt = 8100 / 124.3 = 62.3 °C.

∴ Critical air temperature = 100 - Δ = 37.7°C.

NOTE: Boiling has occurred under full throttle conditions in France with an air temperature of approx. 30 - 32°C.
  
  


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