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Question: use variable specific heats an ideal diesel cycle has a...

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(Use variable specific heats) An ideal diesel cycle has a compression ratio of 20 and uses air as the working fluid. The state of air at the beginning of the compression process is 95 kPa and 20oC. If the maximum temperature in the cycle is not to exceed 2200 K (this corresponds to T3 the highest temperature), determine:

Please follow the instruction given in problem 1 to solve Problem 2 using "variable specific heat".

Ensure that the given answers agree with the given answer key at the end of the image below.

Your help is appreciated!!!

Problem 1. (Use constant specific heats) An ideal diesel cycle has a compression ratio of 20 and uses air as the working fluid. The state of air at the beginning of the compression process is 95 kPa and 20°C. If the maximum temperature in the cycle is not to exceed 2200 K (this corresponds to T3 the highest temperature), determine 1. The temperature at the end of the compression process. Here, use the isentropic relations between 1 and 2 for constant specific heats 2. The cut-off ratio, re, for the cycle. Use the relation given in the previous page between the temperatures at 2 and 3 to determine the cut-off ratio. Note that this relation applies regardless ofwhether we assume constant specific heats or not. 3. The temperature at the end of the expansion process. Again, you may use the isentropic relations between 3 and 4. However, note that the volume ratio does not correspond to the compression ratio. Instead, L-i-. This relation again applies whether you have V, V, V, constant or variable specific heats 4. The thermal efficiency of the cycle. The generic form of the thermal efficiency of the cycle is This relation applies whether you assume constant or variable specific heats. However, there is an even simpler form for constant specific heats, which we will discuss in class Problem 2. Redo problem 1 using variable specific heats Select Answers. T2-912.69 K, r-2.410, ,1,-1 1-4-4 0.565 or 56.5%.

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