METEO 300 Lecture Notes - Lecture 23: Thermal Efficiency, Thermodynamic Cycle, Thermodynamics
Document Summary
Me 300 - lecture 23 - second law of thermodynamics continued. Heat reservoir: a source of heat so large that the extraction of any desire amount of heat does not change the temperature of the reservoir. Heat engine: extracts heat from a high-temperature reservoir and outputs it to produce work. is heat lost to decrease entropy. is heat added to drive the cycle. Cyclic device: fluid returns to initial state (associated with a thermodynamic cycle). *a cyclic device must have more than one reservoir in order to convert heat energy to work. The smaller is to , the greater the efficiency. *the less you subtract from 1 the efficiency). greater the thermal efficiency. We can find the net work using the definition of thermal efficiency: A 50% efficient engine is delivered heat at 10 j/s. = 10 j/s: 0. 5 = 5 j/s. We can find the rate of heat rejection using the overall energy balance:
