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).
Analysis of power losses in the Peregrine exhaust system.
| Identifier | ExFiles\Box 2\10\ 10-page20 | |
| Date | 1st August 1932 | |
| To R.{Sir Henry Royce} From HS{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} c. Sg.{Arthur F. Sidgreaves - MD} Hor. c. S. Du. c. W. Hdv. X 123 HS{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer}4/ADB.8.32. PEREGRINE EXHAUST SYSTEM We have analysed the losses in the Peregrine exhaust system which is an exact copy of the system on J.III, and we append a sketch No. Ms.FF.22 showing the principle dimensions. From the curves it will be noted that no less than 11½ H.P. is lost in this system at 4500 R.P.M. or 73 M.P.H. This is about 16½% and compares unfavourably with the results we have been able to get on the J/25. We think that with the space at our disposal we should be able to reduce the loss to about 5%. The analysis shows that the major loss at present is between the manifold and the silencer, the front bend accounting for no less than 3 H.P. In view of these results, the fact that Peregrine was able to lap at 71.8 M.P.H. with this exhaust system is all the more creditable. hs{Lord Ernest Hives - Chair}/hm.{Capt. W. Hallam - Head Repairs} | ||