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Lecture 3 Advanced Features in EES. By Mary shanti Emai:mpampa1@lsu.edu Phone:389-2963 Department of mechanical Engineering Louisiana State University. Advanced Features in EES. Integration and Differential Equations Table-based integral function Equation-based integral function
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Lecture 3 Advanced Features in EES By Mary shanti Emai:mpampa1@lsu.edu Phone:389-2963 Department of mechanical Engineering Louisiana State University
Advanced Features in EES • Integration and Differential Equations • Table-based integral function • Equation-based integral function • Build-in Functions • Mathematical functions • String functions • Thermophysical property functions
Integral Function • EES has a function called INTEGRAL function which can be used to evaluate an integral and solve differential equations. • The format of integral function is
Two Basic Forms of Integral Function • There are two basic forms of the integral function: • Table-based integral function • Equation-based integral function
Table-based integral function • Table-based Integral function uses the Parametric table to provide the limits and step size of the integration variable. • The integral variable, t, • must be a legal variable name • has values defined in one of the columns of the table • The integrand, f, can be a variable or expression of variables, values, and t.
Equation-Based Integral Function • Equation-based integral function does not require the use of Parametric table. • The format is • F=Integral(f, t, t1, t2, tStep) • or F=Integral(f, t, t1, t2), where t1 and t2 are the lower an upper limits of the integration variable, tStep is the increment EES will use for the integration. If tStep is not provided, EES will use automatic step size.
Differential Equations Any kind of first order differential equations can be rewritten as Where y0 is the initial value of y