It is also possible to modify the Model Constants, but this is not necessary for most applications. For more information about the constants, see Spalart-Allmaras Model through Large Eddy Simulation (LES) Model (in the Theory Guide). Note that C1-PS and C2-PS are the constants and in the linear pressure-strain approximation of Equation 4–231 and Equation 4–232 (in the Theory Guide), and C1’-PS and C2’-PS are the constants and in Equation 4–233 (in the Theory Guide). C1-SSG-PS, C1’-SSG-PS, C2-SSG-PS, C3-SSG-PS, C3’-SSG-PS, C4-SSG-PS, and C5-SSG-PS are the constants , , , , , , and in the quadratic pressure-strain approximation of Equation 4–242 (in the Theory Guide).