At the beginning of the compression process in an air- standard Diesel cycle, p1 = 1 bar and T1 = 300 K. For maximum cycle temperatures of 1200, 1500, 1800, and 2100 K, plot the heat addition per unit of mass, in kJ/kg, the net work per unit of mass, in kJ/kg, the mean effective pressure, in bar, and the thermal efficiency, each versus compression ratio ranging from 5 to 20.

Steel balls 12 mm in diameter are annealed by heating to 1150 k and then slowly cooled to 400 k in an air att 325 k and h -20 w/m2 k. assume the properties of the steel to be k- 40 w/m k,p 7800 kg/m3, and cp 600 j/kg k. a. determine whether lumped system method can be used to analyze this problem and if so why" b. determine the time required for the cooling process. c. determine the total amount of heat lost from each ball to the ambient air