Accession Number : AD0011043


Title :   PRELIMINARY PERFORMANCE STUDIES OF THE MULTI-JET


Descriptive Note : Technical rept.


Corporate Author : CURTISS-WRIGHT CORP SANTA BARBARA CA


Personal Author(s) : BITONDO, D ; KUMM, E L


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/011043.pdf


Report Date : 24 Jan 1953


Pagination or Media Count : 294


Abstract : The engine consists of a large number of tiny pulsejet tubes assembled into a matrix. It differs from the standard pulsejet in that it achieves a shock compression prior to combustion and in addition completes the combustion at constant volume. A typical tube is about 0.25 to 0.5 in. in diam and 6 in. long. A jet unit producing a thrust of 150 lb at a maximum temperature of 3000 deg F would have an 8.25-in. diam, a weight of 43 lb, and a specific fuel consumption of 1.86 lb/hr/lb of thrust. A peak gas temperature of 2500 deg F may be safely considered as the design cruising temperature. There are 160 tubes in the assembly and each tube 240 times/sec. There are 960 thrust pulses/sec. The result is a steady net thrust, since the expansion of each jet occupies about 25% of its firing cycle and the individual radial columns of tubes are fired in sequence. The engine should be much smoother and quieter than the conventional pulsejet. It should provide a simple inexpensive jet unit suitable for helicopters and other subsonic aircraft and missile application. Preliminary design studies indicate that a helicopter powered by multijet engines has a greater range and endurance than can be obtained with other types of power-plants. The preliminary analysis of the engine, including the cycle, the ideal and actual performance of a single tube, the performance of a large supersonic unit, the performance of a small subsonic unit, the materials that can be used, and the feasibility of practical applications, is described in detail. Derivations of the basic equations of the cycle of operation are presented.


Descriptors :   *PULSEJET ENGINES , STEADY STATE , PEAK VALUES , TEMPERATURE , VOLUME , AIRCRAFT , CYCLES , GASES , COMBUSTION , ENDURANCE(GENERAL) , HELICOPTERS , SHOCK , FUEL CONSUMPTION , SUBSONIC CHARACTERISTICS , EQUATIONS , SUPERSONIC CHARACTERISTICS , THRUST , TUBES , COMPRESSION , GUIDED MISSILES


Subject Categories : Jet and Gas Turbine Engines


Distribution Statement : APPROVED FOR PUBLIC RELEASE