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+clc
+// Example 5.3.py
+// Consider a rocket engine burning hydrogen and oxygen combustion chamber temper-
+// ature and pressure are 3571 K and 25 atm, respectively. The molecular weight of
+// the chemically reacting gas in the combustion chamber is 16.0 and gamma1 = 1.22.
+// The pressure at the exit of the convergent-divergent rocket nozzle is 1.174*10^-2
+// atm. The area of the throat is 0.4 m^2. Assuming a calorifically perfect gas,
+// calculate (a) the exit mach number (b) the exit velocity (c) the mass through the
+// nozzle and (d) the area of the exit.
+
+// Variable declaration
+po = 25.0 // combustion chamber pressure (in atm)
+To = 3571.0 // combustion chamber temperature (in K)
+pe = 1.174e-2 // pressure at the exit of the nozzle (in atm)
+Astar = 0.4 // throat area (in m^2)
+gamma1 = 1.22 // ratio of specific heats
+mol_wt = 16.0 // molecular weight (in gms)
+
+// Calculations
+
+// part (a)
+Me = (2/(gamma1-1) *((po/pe**(gamma1-1)/gamma1) - 1)** 0.5) // Exit mach number
+
+// part (b)
+Te_by_To = (pe/po** (gamma1-1)/gamma1) // Te/To
+Te = Te_by_To * To // exit temperature (in K)
+
+R = 8314.0/mol_wt // gas constant (in J/Kg K)
+ae = (gamma1*R*Te** 0.5) // speed of sound at exit (in m/s)
+ve = Me * ae // velocity at exit (in m/s)
+
+// part (c)
+rhoo = po*101325/R/To // density at reservoir (in Kg/m^3)
+rhostar_by_rhoo = (2.0/(gamma1+1)**1/(gamma1-1)) // rhostar/rhoo
+rhostar = rhostar_by_rhoo * rhoo // rhostar, throat density (in Kg/m^3)
+
+Tstar_by_To = 2.0/(gamma1+1) // Tstar/To
+Tstar = Tstar_by_To * To // Tstar, throat temperature (in K)
+astar = (gamma1*R*Tstar** 0.5) // speed of sound at throat (in m/s)
+mass = rhostar*Astar*astar // mass flow rate at throat (in Kg/s)
+
+// part (d)
+rhoe = pe*101325/R/Te // density at exit (in Kg/m^3)
+Ae = mass/rhoe/ve // exit area (in m^2)
+
+// Results
+
+printf("\n Exit mach number %.2f", Me)
+
+printf("\n Exit velocity %.2f m/s", ve)
+
+printf("\n Mass flow rate %.2f Kg/s", mass)
+
+printf("\n Area of the exit %.2f m^2", Ae)
+