Department of Mechanical Engineering ME 322 – Mechanical Engineering Thermodynamics Review for Exam 3

Exam Information 50-minutes (strictly enforced) Resources allowed –The blue properties booklet You can write anything you want in the white space of this booklet. NO photocopies, no taping, pasting, photocopies, or loose papers –A handheld calculator No other electronic devices may be used including cell phones, computers, tablets, music players, etc. 2

Exam Information A table of conversion factors will be provided NO interpolation should be necessary Material covered All assigned reading to date All in-class lecture material to date All in-class problem solutions to date All homework assignments to date 3

Do you know... How to model device efficiency for the following devices? –Pumps –Compressors –Turbines How to determine closed system entropy production? How to determine entropy production for the following open system devices? –Boiler, Condenser, Compressor, Turbine, and Valves How to analyze vapor power cycles? –Determine energy transfer rates (heat and work transfer) associated with each component Pumps, Boilers, Turbines, Condensers, and Feedwater Heaters –Determine cycle performance parameters Thermal efficiency, Heat rate, Back work ratio Represent cycle on Pv and Ts diagrams How to analyze vapor power cycles that have been modified to increase thermal efficiency? –Reheat cycles –Regenerative cycles 4

Do you know... How to analyze gas-turbine based power cycles? –Determine energy transfer rates (heat and work transfer) associated with each component Compressors, Turbines, and Heat Exchangers –Use EES as well as the air tables for these calculation –Determine performance parameters Thermal efficiency, Back work ratio –Represent these cycles on Pv and Ts diagrams How to determine performance parameters for a jet engine? –Propulsive force (engine thrust) –Propulsive power –Propulsive efficiency 5

Do you know... How to analyze internal combustion engine models? –Spark Ignition (Otto Cycle) –Compression Ignition (Diesel Cycle) –Represent these cycles on Pv and Ts diagrams –Determine work transfer, heat transfer, and change in internal energy for the following processes? Compression, Heat Addition, Expansion, and Heat Rejection –Determine performance parameters Thermal efficiency, mean effective pressure Estimate power output given rotational speed and engine type How to analyze vapor compression refrigeration cycles? –Determine energy transfer rates for each component Evaporator, Compressor, Condenser, and Throttling Valve –Represent these cycles on Ph diagrams –Determine performance parameters COP C for a refrigeration cycle COP H for a heat pump cycle 6

Do you know... Know the refrigeration jargon? –SET – saturated evaporating temperature –SCT – saturated condensing temperature –DSH – degrees of superheat –DSC – degrees of subcooling –Refrigeration effect –Refrigeration capacity How to determine the properties of mixtures of ideal gases? –Molar Mass, gas constant, heat capacity ratio –PvT behavior, internal energy, enthalpy, entropy How to convert between mixture mass fraction and mixture mole fraction? How to use Daltons Law of Partial Pressures? 7