Constants and information that you may need: Drag force = Cd0.5pu Af Universal gas constant, R...

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Constants and information that you may need: Drag force = Cd0.5pu Af Universal gas constant, R = 8.3143 x 103 J/kmol-K. Solid propellant burning rate, r = = ap Steady state solid propulsion combustion chamber pressure: Ab a (pp - Po) Po= A* (+ RTO (741) 2 + 1) ( y 1) - + aA+BBC+vD Keq,n = pa+B--v Keq,p XCeqXDeq Keq,n = B XAeqX Beq (1 n) where is the mole fraction. Exhaust velocity, ue, in terms of molecular mass of mixture, M, stagnation chamber temperature, To, and exit to stagnation cham- ber pressure ratio, Pe PO' ue = Flight Dynamics V (Y - 1) / Pe To 1 - 2R (Y - 1) M To du F dt m where F is thrust. Mathematical expressions: Po D m - g cos 0 sinh u = cosh u 1- (eu - e-u) 1 = 2 (e + e ) sinh-12 = ln (x+x+1) cosh 1x = In (x + x - 1) 5. A hybrid rocket motor is constructed with three ports with initial and final port diameters of 0.15 and 0.25 m, respectively. The burn rate is, r = 2.75 10-4G0.6 m/s where the units of G, are in kg/ms and the product of the fuel density times the grain length is 3.4 103 kg/m. (a) Without calculations, how does the oxidizer to fuel mass flow ratio vary with time? (b) How much fuel has been consumed in the first third of the burn time? (c) 4-credit students: If the burn time is 70 s, what is the oxidizer mass fuel rate in kg/s? Constants and information that you may need: Drag force = Cd0.5pu Af Universal gas constant, R = 8.3143 x 103 J/kmol-K. Solid propellant burning rate, r = = ap Steady state solid propulsion combustion chamber pressure: Ab a (pp - Po) Po= A* (+ RTO (741) 2 + 1) ( y 1) - + aA+BBC+vD Keq,n = pa+B--v Keq,p XCeqXDeq Keq,n = B XAeqX Beq (1 n) where is the mole fraction. Exhaust velocity, ue, in terms of molecular mass of mixture, M, stagnation chamber temperature, To, and exit to stagnation cham- ber pressure ratio, Pe PO' ue = Flight Dynamics V (Y - 1) / Pe To 1 - 2R (Y - 1) M To du F dt m where F is thrust. Mathematical expressions: Po D m - g cos 0 sinh u = cosh u 1- (eu - e-u) 1 = 2 (e + e ) sinh-12 = ln (x+x+1) cosh 1x = In (x + x - 1) 5. A hybrid rocket motor is constructed with three ports with initial and final port diameters of 0.15 and 0.25 m, respectively. The burn rate is, r = 2.75 10-4G0.6 m/s where the units of G, are in kg/ms and the product of the fuel density times the grain length is 3.4 103 kg/m. (a) Without calculations, how does the oxidizer to fuel mass flow ratio vary with time? (b) How much fuel has been consumed in the first third of the burn time? (c) 4-credit students: If the burn time is 70 s, what is the oxidizer mass fuel rate in kg/s?