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 heat transference in exhaust and induction systems and its effect on engine operation.
| Identifier | ExFiles\Box 13\3\ 03-page070 | |
| Date | 21th January 1929 | |
| Hs{Lord Ernest Hives - Chair}/ACL1/T21.1.29 -3- Contd. velocity is only very low in the full bore exhaust pipe and no doubt would be practically nil round the circumference of the pipe forming an insulating skin. This combined with its low specific heat would result in slow transference of heat to the interior of the boiler. We have proved that the gas velocity is an important factor determining the rate of heat transference. Again the steam rapidly became quenched at the cold induction bend jacket as it issued in small quantities from the boiler. Once the superheated system arrived at its normal working capacity the mean hot spot temp. was naturally higher than with water heat, but this appeared to be of no advantage compared with water heating providing the latter system was not below 70° C. Our experience has been that under normal working conditions we do not need intense heat at the induction bend to insure good distribution, and consequent 'sweetness' of engine operation. This quality of sweetness of operation an engine response must be contributed to largely by the high air temperature obtained under the bonnet of the car during running conditions, because supplying the latent heat of evaporation by means of the ingoing air appears the most logical means of providing an easy distributable mixture. Such a method by itself, however, would be of little use due to the considerable time before benefit could be derived from this source after starting up from cold. (Contd.) | ||