QUESTION FOUR: A four-cylinder turbo-charged diesel engine has a compression ratio of 22:1. At the start of the compression stroke cylinder No. I contains 0.25kg of air at a pressure of 100kN/m² and a temperature of 65°C. The air is then compressed according to the law P1.32 = c, a constant. The mass of the fuel injected amounts to '/soth of the mass of air in the cylinder. If combustion occurs under conditions of constant pressure and the calorific value of the fuel used is 44.5MJ/kg, determine: (a) The temperature after compression, (b) The work done on the air during compression, and (c) The temperature after combustion. Given: Q=mfuel x Ho [Take Cp for the mixture as 995J/kg K] Q = m CpAT n-1 n T₂ = T₁ (²²) 7² P₂ = P₁ (1/1²) Cp n Cv 1.32 W₁ = P₁V₁-P₂V₂ n-1 R=Cp-Cv PV= mRT PV = C

QUESTION FOUR: A four-cylinder turbo-charged diesel engine has a compression ratio of 22:1. At the start of the compression stroke cylinder No. I contains 0.25kg of air at a pressure of 100kN/m² and a temperature of 65°C. The air is then compressed according to the law P1.32 = c, a constant. The mass of the fuel injected amounts to '/soth of the mass of air in the cylinder. If combustion occurs under conditions of constant pressure and the calorific value of the fuel used is 44.5MJ/kg, determine: (a) The temperature after compression, (b) The work done on the air during compression, and (c) The temperature after combustion. Given: Q=mfuel x Ho [Take Cp for the mixture as 995J/kg K] Q = m CpAT n-1 n T₂ = T₁ (²²) 7² P₂ = P₁ (1/1²) Cp n Cv 1.32 W₁ = P₁V₁-P₂V₂ n-1 R=Cp-Cv PV= mRT PV = C

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

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