GB791986A - Liquid fuel supply system for aerial bodies - Google Patents

Abstract

791,986. Jet propulsion plant. LUCAS (INDUSTRIES), Ltd., J. Feb. 10, 1956 [Feb. 11, 1955], No. 4105/55. Class 110 (3). [Also in Group XXIX] A liquid fuel supply system for a ram jet aerial body comprises the combination of a pair of centrifugal pumps a, b, operated by a turbine e driven by ram air at f, throttles 4, 5, respectively, in each pump delivery duct c, d, actuated by servo-control means, one of these means being responsive at least in part to ram air pressure, e.g. at 16, and the other responsive to the fuel pressure, e.g. at 23, in the delivery duct c controlled by ram pressure. A by-pass cock h for the turbine ram air is actuated by pressure in c via n acting on a spring-loaded piston j, leakage through a piston orifice m being controlled by a hinged valve p moved by a piston x responsive to pressure in c and an evacuated bellows u responsive to atmospheric pressure opposed by a diaphragm v responsive to ram air pressure. Throttle 4 is actuated by pressure in c acting on a spring-loaded piston 7, leakage through a piston orifice 9 being controlled by a hinged valve 11 moved by differential diaphragms 15, the diaphragms space 14 opening to atmosphere, the space between the diaphragms opening to ram pressure in pipe 16 leading to atmosphere through two restrictions, the second of which is preferably choked, and the outer space of the larger diaphragm opening between the restrictions. The leakage path 10 is also controlled by a piston valve 18 actuated by differential diaphragms 19, 20. Should the valve 4 throttle unduly, the valve inlet pressure acts on the smaller diaphragm 19 to close the part 10 and re-open the valve. The valve 5 maintains the pressure in pipe d equal to the pressure in pipe c by having the leakage through its actuating piston controlled by a diaphragm valve 27 responsive respectively to the pressures in pipes d and c via passages 30 and 17, 26, 23. Pilot burner pipes 31, 32 lead from the main pipes c, d. In a modification, the action of throttle 4 is reversed and this throttle is bypassed by a spring-loaded relief valve opened by inlet pressure to ensure a minimum fuel flow, while in each pipe c, d, between throttles 5 and 4 and pumps b and a, respectively, a further servothrottle is positioned, the first being controlled as at m, p, q, u and x, the diaphragm v being omitted, the piston x being responsive to throttle outlet pressure and the bellows u to ram pressure, and the second being controlled as at 27 to give equal flows. In a further embodiment a valve as at 11, 16, 15 controls a leak-off from the end of another pipe similar to 16 and from which the ram pressure between the restrictions acts on a bellows to operate a second control valve for the piston 7 and throttle 4. In this embodiment, the pilot burner flows at 31, 32, have throttles controlled, one as at 27 and the other as at m, p, q, x and u except that diaphragm v is omitted, ram pressure acts in the same direction on the bellows and one side of the piston, and throttle outlet pressure acts on the other side of the piston.