Performance of an experimental polyethylene solid fuel ramjet

An experimental investigation on the characteristics of polyethylene combus tion in a solid fuel ramjet is reported. An experimental expression for the Fuel regression rate is presented for the conditions of the tests: r = 2.7 8 x 10(-3) p(0.8) (c)G(0.35) T-air(air)0.36, where the units of r are mm s( -1), p(c) is the chamber pressure (atm), G(air) is the air mass Aux (g cm(- 2) s(-1)) and T-air is the air inlet temperature (K). Additionally, the eff ects of the introduction of an intermediate mixing chamber and of the incre ase in the post mixing chamber length over the combustion efficiency are st udied. Radiation loss transfer rates are also analysed and discussed. The p arameter was obtained by the use of a translucid polyethylene grain, which was first operated bare and later covered with an insulation aluminium shee t. Experimental results trends agree with those of previous works conducted with systems of similar geometry and different fuels. (C) 1999 Elsevier Sc ience Ltd. All rights reserved.