Solid Fuel Ramjets

N.P.Dulepov, G.K.Kotenkov, L.S.Yanovskiy

Central Institute of Aviation Motors (CIAM), State Research Center of Russian Federation

2, Aviamotornaya Str., Moscow, Russia, 111250

Telex: 411686 CIAM SU

There are presented the methods of regulation of mass flow rate and chemical composition of solid propellant (SP) for Ramjets/Ramrockets (RJ/RRJ). These methods are based on experimental and analytical studies carried out at the CIAM. There are shown the advantage of the scheme Ramrocketjet with divided and combined grains (charges) – SPRRJ_DCG (solid propellants Ramrocket jets with divided and combined grains which include solid propellants and high energy fuels and high energy solid propellants–heat protection) – in comparison with another types of RJ/RRJ. It has allowed on the basis of experimental and computational researches to develop a methodology of a flight vehicles powered SPRRJ_DCG which include another types of motors (solid rocket motors – SRM, SRM + Ramjets, SRM + RRJ etc.). The methodology allows to determine an optimum chemical composition SP, to select an optimal regime of engine operation and optimal programs for SP mass flow rate regulation. The range of SP mass flow rate regulation at RRJ_DCG charges can be 1: 30 vs. 1: 7 for usual Ramjets/Ramrockets. The range of SP mass flow rate regulation is function of types of SP and high-energy fuels and high–energy solid propellants–heat protection. It is depend from tactical requests to flight vehicles.

At the CIAM developed the computer codes for calculation of parameters for different types of Ramjets/Ramrockets (RAMJET). These codes can be used for calculation both an engine parameters and a system “propellant–engine–flight vehicle“. It is possible to improve an tactical–technical characteristics for flight vehicles powered with Ramjets/Ramrockets by means of application of CIAM’s developed methodology of designing.

NOTATIONS:

─ Wide experimental tests and analysis of solid-fuel ramjets of various configurations were performed at CIAM.

─ The design technique of power plants with SFRJ/SPRR for multi-role vehicles was developed. The technique made possible to find optimal fuel composition, and to make a choice of operating conditions and optimal control laws of SP flow rate.

─ The proposed technique can provide 1:30 control band of SP flow rate as compared with gas generator ramjets (1:7). The control band of SP flow rate and composition as well as chemical composition of combustion products in air depends on the type of SP, HEF, and HEHPM, and, mainly, is determined by vehicle performances.

─ “RAMJET” software package was developed at CIAM for analysis of ramjets of different configurations. This software can be useful for prediction of engine performances as well as “fuel-engine-vehicle” characteristics in flight.