Thermodynamics Homework 12 – due Friday November 22 nd You may complete this assignment individually, or with anyone in your assigned group. Please include both your team number and the ME-ID’s of all students who contributed to it. Your team number will only be used to return the assignment to you in your file folder. 1. The minimum enclosed volume (at TDC) in a single-cylinder four-cycle Diesel engine is 5.5% of the maximum enclosed volume (at BDC). The cylinder contains 10 g of gas. The gas is at 27 °C at 100 kPa at the beginning of the compression process and at 1400 °C at the end of the heat addition process. a. Draw the process on P-V and T-S diagrams. b. Determine the cutoff ratio (see Section 9-6) c. Determine the power output of the engine in horsepower if it turns at 1800 rpm. (27+273)*(1/0.055)^0.4=957.1416 1 to 2 = isentropic compression (1400+273) / 960=1.7427 2 to 3 = constant pressure heat addition 1673*(1.743*0.055)^0.4=654.8774 1.005*(1673-960) - 0.718*(655-300)=461.675 1800/60 * 1/2 * 462 * 0.010 * 1000 * 1/745.7 = 92.9328
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Thermodynamics Homework 12 – due Friday November 22nd You may complete this assignment individually, or with anyone in your assigned group. Please include both
your team number and the ME-ID’s of all students who contributed to it. Your team number will only be
used to return the assignment to you in your file folder.
1. The minimum enclosed volume (at TDC) in a single-cylinder four-cycle Diesel engine is 5.5% of the maximum
enclosed volume (at BDC). The cylinder contains 10 g of gas. The gas is at 27 °C at 100 kPa at the beginning of the
compression process and at 1400 °C at the end of the heat addition process.
a. Draw the process on P-V and T-S diagrams.
b. Determine the cutoff ratio (see Section 9-6)
c. Determine the power output of the engine in horsepower if it turns at 1800 rpm.