Visualization of reacting shock wave in single pulse supersonic combustion tube

Flame propagation through a single pulse supersonic combustion tube with test section was studied experimentally. The supersonic combustion tube which is 3 meter long has three section (Section A, B and C). A 1.5 meter orifice plate is installed from Section A to B to generate an accelerating turbulence for the laminar combustion wave. Two types of fuel gases were used which are Methane and Propane with Oxygen as oxidizer. The motivation for this research mainly comes from the initiative in designing and developing of Rotating Supersonic Combustion Engine (RSCE). The effect of equivalence ratio (Ф) on pressure, velocity and Mach number were investigated experimentally in supersonic combustion experiments. The experimental results obtain were compared with the numerical result by using Chemical Equilibrium with Applications (CEA) software. In order to visualize the Schlieren images of the reacting shock wave for the hydrocarbon mixtures, test section with an optical window access is installed at the end of the supersonic combustion tube. Results showed that the experimental readings of supersonic combustion pressure and velocity were within the percentage errors of 10% as compared to the numerical readings obtained from CEA software. When a supersonic combustion wave front propagates from one place to another, it leaves cell width that shows the reactivity of the mixture. The smaller the cell width size, the higher the reactivity of the mixtures. From the results obtained, Propane-Oxygen mixture at Ф = 0.6 shows smaller size of the supersonic combustion wave front as compared to the Methane-Oxygen mixture at Ф = 0.6 and Ф = 0.8.