A turboprop engine (Fig. 9.27a) consists of a diffuser, compressor, combustor, turbine, and nozzle. The turbine drives a propeller as well as the compressor. Air enters the diffuser at 12 lbf/in.2 , 4608R, with a volumetric flow rate of 23,330 ft3 /min and a velocity of 520 ft/s. In the diffuser, the air decelerates to negligible velocity. The compressor pressure ratio is 9, and the turbine inlet temperature is 21008R. The turbine exit pressure is 25 lbf/in.2 , and the air expands to 12 lbf/in.2 through a nozzle. The compressor and turbine each have an isentropic efficiency of 87%, and the nozzle has an isentropic efficiency of 95%. Combustion occurs at constant pressure. Flow through the diffuser is isentropic. Using an air-standard analysis, determine (a) the power delivered to the propeller, in hp. (b) the velocity at the nozzle exit, in ft/s. Neglect kinetic energy except at the diffuser inlet and the nozzle exit.
Tragedy of the Commons : Resource common to all, used by many but no one is responsible - England Example - Bass, L obster ( easons, L imits (Size, nd umbers) - Lobster w as actually consider it Fertilizer” - AIR QUALITY: No one is individually responsible for the whole problem, or fixing the problem. - Has led to government policy - Individuals who pollute or don’t pollute have the same benefit but different costs. - Hybrid (New) vs. My Jeep - He has a car that he ma
