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+clc
+// Given that
+N = 16000 // Speed in RPM
+t1 = 17 // Intake temperture of gas in degree centigrade
+rp = 4 // Pressure ratio
+sigma = 0.85// Slip factor
+n_iso = 0.82 // Isentropic efficiency
+alpha_wirl = 20 // Pre-wirl angle in degree
+d1 = 200 // Mean diameter of impeller eye in mm
+V1 = 120 //Absolute air velocity in m/s
+gama = 1.4 // Ratio of heat capacities
+cp = 1.005 // Heat capacity in kJ/kgK
+printf("\n Example 19.20\n")
+T1 = t1 + 273
+T2s = T1*((rp)^((gama-1)/gama))
+delta_Ts = T2s-1
+delta_T = delta_Ts/n_iso
+Wc = 1 *cp*delta_T
+Vb1 = (%pi*d1*(1e-3)*N)/60
+Vw1 = V1*sind(alpha_wirl)
+Vb2 = 459.78 // By solving quadratic equation 172.81e3=0.85*Vb2^2-167.55*41.05
+d2 = Vb2*60/(%pi*N)
+
+printf("\n Impeller tip diameter = %f mm",d2*1000)
+// The answer given in the book varies due to round off error
+