A GRAPHICAL METHOD OF CALCULATING GAS ENGINE EFFICIENCIES. (INCLUDING PLATE AT BACK OF VOLUME)

E W HOLLINGWORTH
1908 Minutes of the Proceedings of the Institution of Civil Engineers  
THE following is an explanation of a graphic method for calculating the theoretical efficiency of gas-engines. The specific heats and other data are taken from a Paper by Mr. Leonard Bairstow.1 From general thermo-dynamic relations where H denotes heat added (in foot-lbs.). kv " specific heat a t constant volume (in foot-lbs.). t " absolute temperature in degrees Centigrade. P " absolute pressure in pounds per square foot. V " volume in cubic feet. I n adiabatic expansion or compression d H =
more » ... compression d H = 0, and the equation becomes k , d t = -p d~, but for a gas p V = R t, therefore by substitution for y and integrating R. If v1 and 2r2 be any particular values of W, and t , and t, the corrcsponding temperatures, log c may be eliminated, and Where to is any convenient value of t which may be chosen as the starting point. Gas-Engine Efficienciea," Engineehng, vol. lxxxiii, p. 731. S 2 Downloaded by [ University of Liverpool] on [17/09/16]. Copyright © ICE Publishing, all rights reserved. of " apparent" specific heats which differ considerably from those given above. It should, however, be noticed that although the difference between these Tables amounts a t some points to 15 per
doi:10.1680/imotp.1908.17595 fatcat:lmqavvg45jbetaxdw6i36n3z7a