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 heat dissipation and condenser design for Phantom engines.
| Identifier | ExFiles\Box 25\1\ Scan004 | |
| Date | 31th October 1929 | |
| -2- Lrl/AD31.10.29 contd. Amount of heat to be dissipated. From heat to jacket tests carried out, it would appear that the equivalent horse power rejected to cooling water is approximately equal to the B.H.P. developed in the Phantom engines. If we allow 120 HP. at 2000 R.P.M. this will cover the conditions of max. torque which occur at a lower speed. Condenser. I suggest we used the standard long tube 10 m.m. dia x 420 m.m) aero radiator tube block, triangular in shape which conforms to the rate of steam condensation and materially assists in ejecting the air. With this size tubed radiator, horsepower dissipated per sq. ft. frontal area = V / 73 where V = air velocity in ft/mins. assuming an air velocity through tubes of 80 M.P.H. induced by fan, V = 7000 ft/min. and HP/ф frontal area = 7000 / 73 = 96. ∴ Required frontal area = 120 / 96 = 1.25 ф assuming an equilateral triangular condenser the length of each side would be a = √(A / .433) = √(1.25 / .433) = 1.7 ft say 1' 9" | ||