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).
Correction of aero engine B.HP for atmospheric humidity.
| Identifier | ExFiles\Box 37\3\ scan 124 | |
| Date | 22th October 1917 | |
| To EP.{G. Eric Platford - Chief Quality Engineer} from EFC. c. to EH. X. 3178 EFC4/T22.10.17. X.3202 - CORRECTION TO AERO ENGINE B.H.P. FOR ATMOSPHERIC HUMIDITY, In answer to your note EP{G. Eric Platford - Chief Quality Engineer}/HS{Lord Ernest Hives - Chair}50/R191017, asking for information re atmospheric humidity, we have given this matter consideration and we are now in a position and have the necessary tables for the determination of the total quantity of water vapour contained in any given quantity of air, when the readings of the wet and dry bulb thermometers of a hygrometer are known. It is quite impossible to predict exactly what law the variation of horse power will follow in relation to the amount of water vapour in the air; one can only say that the horse power would, as you have already found, diminish with increase of this factor. In order to arrive at a definite law of variation, it will be necessary to have some experimental observations, and for this purpose we must, of course, have a wet and dry bulb hygrometer. We have talked this matter over with Mr. Hives and he is going into town this morning and will see if he can obtain a self contained wet and dry bulb hygrometer. I have suggested that it will be better to have two of these, one for our Dept, and one for yours, and he will see what can be done in the matter. What we suggest is that as many observations as possible should be taken on engines on test of the Contd. | ||