Transcription of RANKINE POWER GENERATION CYCLE
{{id}} {{{paragraph}}}
Example: barber
RANKINE POWER GENERATION CYCLE
RANKINE POWER GENERATION CYCLE A heat ENGINE: PRODUCES WORK FROM heat BY WASTING A FRACTION OF heat INPUT TO A LOW TEMPERATURE RESERVOIR T oC s (kJ/kg-K) 4 3 21 CHARACTERISTICS 1. RANKINE CYCLE is a heat engine comprised of four internally reversible processes. Significance: area enclosed by process lines equals the net heat transfer by Clausius Principle for internally reversible processes: dQ = TdS for a CYCLE : =TdSQnet and by the First Law for a CYCLE : Qnet = Wnet Wturbine + Wpump = QH + QL where Wturbine is positive, Wpump is negative, QH is positive, QL is negative, |QH| > |QL| and |Wturbine| > |Wpump|. 12. Process analysis using the First Law: Process Phases Device 1st Law expression1 2 adiabatic and reversible (isentropic) compressioninput: wpumpSaturated Liquid Compressed liquid pump wpump = (h2 h1) = v(P2 P1) 2 3 isobaric expansion qH = heat input from high temp reservoir Liquid Superheated (usually) vapor boiler qH = (h3 h2) 3 4 adiabatic and reversible (isentropic) expansion output: wturbine >> wpumpSuperheated vapor Liquid-vapor mixture (usually) turbine wturbine = (h4 h3) 4 1 isothermal a
3. Heat transfer in the ideal Rankine Cycle relies on phase change, a very efficient way to store and release energy. The working fluid is usually water/steam. During the cycle, the properties of the working fluid change as below with associated heat/work exchanges. h (kJ/kg) P (kPa) T (oC) s (kJ/kg-k) q or w (kJ/kg) 1Æ2 Small increase h1 = hf ...
Tags:
Information
Domain:
Source:
Link to this page:
Please notify us if you found a problem with this document: