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Description	<div style="color: rgb(68, 68, 68); font-family: Consolas; font-size: 15px;">In thermodynamics, an isentropic process is an ideal thermodynamic process that is adiabatic and reversible. In this system, the transfer of work is friction less and there is no net transfer of heat or mass. </div><div style="color: rgb(68, 68, 68); font-family: Consolas; font-size: 15px;"><br></div><h2 style="margin: 0px; position: relative; font-variant-numeric: normal; font-variant-east-asian: normal; font-variant-alternates: normal; font-kerning: auto; font-optical-sizing: auto; font-feature-settings: normal; font-variation-settings: normal; font-variant-position: normal; font-weight: bold; font-stretch: normal; font-size: 14px; line-height: normal; font-family: "Trebuchet MS", Trebuchet, sans-serif; color: rgb(0, 0, 0);"><span style="font-family: Consolas;">Formula of Isentropic efficiency of steam turbine</span></h2><div style="color: rgb(68, 68, 68); font-family: Consolas; font-size: 15px;"><br></div><div style="color: rgb(68, 68, 68); font-family: Consolas; font-size: 15px;">The isentropic efficiency is the ratio of actual power to the isentropic power and this isentropic efficiency of a steam turbine can be calculated using the following formula:</div><div style="color: rgb(68, 68, 68); font-family: Consolas; font-size: 15px;"><br><b>η = (hi - ho) / (hi - hos)</b></div><div style="color: rgb(68, 68, 68); font-family: Consolas; font-size: 15px;"><b><br></b>Here,<br>hi     : enthalpy of the steam at the inlet of the turbine (btu/lb) <br>ho    : enthalpy of the steam at the outlet of the turbine (btu/lb)<br>hos   : isentropic enthalpy of the steam at the outlet of the turbine (btu/lb)<br><br></div><h2 style="margin: 0px; position: relative; font-variant-numeric: normal; font-variant-east-asian: normal; font-variant-alternates: normal; font-kerning: auto; font-optical-sizing: auto; font-feature-settings: normal; font-variation-settings: normal; font-variant-position: normal; font-weight: bold; font-stretch: normal; font-size: 14px; line-height: normal; font-family: "Trebuchet MS", Trebuchet, sans-serif; color: rgb(0, 0, 0);"><span style="font-family: Consolas;">Python code</span></h2><div style="color: rgb(68, 68, 68); font-family: Consolas; font-size: 15px;"><br></div><div style="color: rgb(68, 68, 68); font-family: Consolas; font-size: 15px;">The following is a Python example that calculates the isentropic efficiency of a steam turbine when superheated steam at 600 psig, 700 degF operates the turbine and is extracted at 60 psig, 350 degF.</div><div style="color: rgb(68, 68, 68); font-family: Consolas; font-size: 15px;"><br><span style="color: rgb(43, 0, 254);">from pyXSteam.XSteam import XSteam</span><span style="color: rgb(43, 0, 254);"><br></span><span style="color: rgb(43, 0, 254);"><br></span></div><div style="color: rgb(68, 68, 68); font-family: Consolas; font-size: 15px;"><span style="color: rgb(43, 0, 254);">steamTable = XSteam(XSteam.UNIT_SYSTEM_FLS) # ft/lb/sec/°F/psi/btu</span><span style="color: rgb(43, 0, 254);"><br></span><span style="color: rgb(43, 0, 254);"><br></span></div><div style="color: rgb(68, 68, 68); font-family: Consolas; font-size: 15px;"><span style="color: rgb(43, 0, 254);">def isentropicefficiency(Pi, Ti, Po, To):</span><span style="color: rgb(43, 0, 254);"><br></span><span style="color: rgb(43, 0, 254);">    hi = steamTable.h_pt(Pi + 14.696, Ti)</span><br><span style="color: rgb(43, 0, 254);">    ho = steamTable.h_pt(Po + 14.696, To)</span><br><span style="color: rgb(43, 0, 254);">    si = steamTable.s_ph(Pi + 14.696, hi)</span><br><span style="color: rgb(43, 0, 254);">    hos= steamTable.h_ps(Po + 14.696, si)</span><br><span style="color: rgb(43, 0, 254);">    </span><br><span style="color: rgb(43, 0, 254);">    return (hi - ho) / (hi - hos) * 100</span></div><div style="color: rgb(68, 68, 68); font-family: Consolas; font-size: 15px;"><span style="color: rgb(43, 0, 254);"><br></span><span style="color: rgb(43, 0, 254);"># from 600 psig + 700 degF to 60 psig + 350 degF</span><br><br></div><div style="color: rgb(68, 68, 68); font-family: Consolas; font-size: 15px;">When run the code, you get the results below.</div><div style="color: rgb(68, 68, 68); font-family: Consolas; font-size: 15px;"><br><span style="color: rgb(43, 0, 254);">hi : enthalpy of steam Pi, Ti (btu/lb) = 1350.1</span><br><span style="color: rgb(43, 0, 254);">si : entropy  of steam Pi, Ti (btu/lb-F) = 1.584</span><br><span style="color: rgb(43, 0, 254);">ho : enthalpy of steam Po, To (btu/lb) = 1205.5</span><br><span style="color: rgb(43, 0, 254);">so : entropy  of steam Po, To (btu/lb-F) = 1.657</span><br><span style="color: rgb(43, 0, 254);">hos : isentropic enthalpy of steam Po, si (btu/lb) = 1149.6</span><br><span style="color: rgb(43, 0, 254);">isentropicefficiency </span><span style="color: rgb(43, 0, 254);">= (1350.1 - 1205.5) / (1350.1 - 1149.6) * 100 = 71.1</span><br><span style="color: rgb(43, 0, 254);">isentropicefficiency = 72.1</span></div><div style="color: rgb(68, 68, 68); font-family: Consolas; font-size: 15px;"><span style="color: rgb(43, 0, 254);"><br></span></div><div class="separator" style="color: rgb(68, 68, 68); font-family: Consolas; font-size: 15px; clear: both;"><a href="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjMo-ENzmhFiKqXSzo9OCNAdE6CMocGNkPPsnbqz6Qi7Vc_O2tgXM_VwxzZYV7F_b2jqlP__Ql_-on3QE34PMP8fAWfPbkaOJ010yiENQoLIHUfDKcOhXoVSkIg7U1BxzkECIbTtCro0KAmoqa0pABHcDJWAd4Bm0z5H-3tTxtYu8GRZag4KKHi1bVmIAA/s600/steamturbineeff.png" style="color: rgb(209, 102, 63); margin-left: 1em; margin-right: 1em;"><img border="0" data-original-height="256" data-original-width="600" height="186" src="https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjMo-ENzmhFiKqXSzo9OCNAdE6CMocGNkPPsnbqz6Qi7Vc_O2tgXM_VwxzZYV7F_b2jqlP__Ql_-on3QE34PMP8fAWfPbkaOJ010yiENQoLIHUfDKcOhXoVSkIg7U1BxzkECIbTtCro0KAmoqa0pABHcDJWAd4Bm0z5H-3tTxtYu8GRZag4KKHi1bVmIAA/w435-h186/steamturbineeff.png" width="435" style="border-width: initial; border-style: none; position: relative;"></a></div><div class="separator" style="color: rgb(68, 68, 68); font-family: Consolas; font-size: 15px; clear: both;"><br></div><div style="color: rgb(68, 68, 68); font-family: Consolas; font-size: 15px;"><span style="color: rgb(43, 0, 254);">print("isentropicefficiency = ", isentropicefficiency(600, 700, 60, 350))</span></div><div style="color: rgb(68, 68, 68); font-family: Consolas; font-size: 15px;"><span style="color: rgb(43, 0, 254);"><br></span></div>