Question

(i) Look up the four thermodynamic processes that compose an Otto cycle. Give the correct thermodynamic name for each process in the Otto cycle. Which properties stay constant during each process? (ii) Sketch pressure-volume (P-V) and temperature-entropy (T-S) diagrams for the Otto cycle. ČLEARLY LABEL THE ENDPOINTS OF EACH PROCESS. Begin with the start of the compression stroke. (iii) Make a table that shows the sign (-ve , 0, +ve) of heat transfer, work transfer, and change in internal energy associated with each process the makes up the Otto cycle. (iv) Shade the area on the P-V diagram which represents the NET work output. (v) Shade the area on the T-S diagram which represents heat transfer INTO the cycle. (vii) Explain how to use data from the T-S diagram to estimate the Otto cycle efficiency. ) Shade the area on the T-S diagram which represent the NET work output. viii) Predict changes in Otto cycle efficiency due to decreased compression ratio.Justify your reasoning using your P-V and T-S diagrams.

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