Advanced Power Cycles and Power Cycle Components/Processes Analysis

Description

The ideal, simple and basic power cycles (Carnot Cycle, Brayton Cycle, Otto Cycle and Diesel Cycle) and ideal power cycle components/processes (compression, combustion and expansion) are presented in this course material.

When dealing with power cycles two different approaches are taken with respect to the working fluid.  For Carnot Cycle and Brayton Cycle, air, argon, helium and nitrogen are considered as the working fluid.  For Otto Cycle and Diesel Cycle, only air is used as the working fluid.

When dealing with power cycle components/processes (compression and expansion), air, argon, helium and nitrogen are used as the working fluid.

When dealing with combustion, six different fuels (carbon, hydrogen, sulfur, coal, oil and gas) react with air and oxygen enriched air as the oxidant at different stoichiometry values (stoichiometry => 1) and oxidant inlet temperature values.

For each power cycle thermal efficiency derivation is presented with a simple mathematical approach.  Also, for each power cycle, a T - s diagram and power cycle major performance trends (thermal efficiency, specific power output, power output, combustion products composition on weight and mole basis, specific fuel consumption and stoichiometry) are plotted in a few figures as a function of compression ratio, turbine inlet temperature and/or final combustion temperature and working fluid mass flow rate.  It should be noted that this course material does not deal with costs (capital, operational or maintenance).

For compression and expansion, the technical performance of mentioned power cycle components/processes is presented with a given relationship between pressure and temperature.  While for combustion, the technical performance at stoichiometry => 1 conditions is presented knowing the specific enthalpy values for combustion reactants and products, given as a function of temperature.  This course material provides the compression and expansion T - s diagrams and their major performance trends plotted in a few figures as a function of compression and expansion pressure ratio and working fluid mass flow rate.  For each combustion case considered, combustion products composition on both weight and mole basis is given in tabular form and plotted in a few figures.  Also, flame temperature, stoichiometric oxidant to fuel ratio and fuel higher heating value (HHV) are presented in tabular form and plotted in a few figures.  The provided output data and plots allow one to determine the major combustion performance laws and trends.

In this course material, the student gets familiar with the ideal simple and basic power cycles, power cycle components/processes and compressible flow components and their T - s and h - T diagrams, operation and major performance trends.