Continuous multifront detonation of kerosene mixtures with air heated in the settling chamber

Regimes of continuous multifront detonation of two-phase mixtures of aviation kerosene and hot air are obtained for the first time and studied in a flow-type annular combustor 503 mm in diameter and 600 mm long. Air with a flow rate of 7.8 $\div$ 24 kg/s is preheated up to 600 $\div$ 1200 K by a firing method in the settling chamber by means of burning a stoichiometric H$_2$–O$_2$ mixture. Liquid kerosene is bubbled with air in the fuel injection system. The equivalence ratio of the fuel is 0.66 $\div$ 1.28. The influence of the air temperature on the region of continuous detonation, pressure in the combustor, and specific impulse is studied. Experiments with the air temperature in the interval 600 $\div$ 1200 K reveal regimes of continuous multifront detonation with one pair (frequency 1.2 $\pm$ 0.1 kHz) or two pairs (frequency 2.4 $\pm$ 0.2 kHz) colliding transverse detonation waves. Based on the stagnation pressure measured at the combustor exit, the thrust force and specific impulse are determined. It is shown that an increase in the air temperature assists in detonation burning of the two-phase kerosene-air mixture, but the degree of dissociation of combustion products increases, while the specific impulse of the thrust force decreases. The specific impulse increases if the amount of the fuel in the mixture is sufficiently small, and its maximum value with allowance for the energy of compressed air in receivers is approximately 2200 for the air temperature in the settling chamber equal to 600 K.