Experimental Investigation of Film Cooling with Tangential Slot Injection in a LOX/CH4 Subscale Rocket Combustion Chamber

Abstract

Within the frame of a broader activity towards research into the application of methane in cryogenic liquid rocket engines, the efficiency of film cooling was studied in a LOX/CH 4 fired subscale sized model combustor. Aiming at booster as well as upper stage applications, the combustion pressure levels have been varied between 4 MPa and 7 MPa. The effectiveness of the ambient temperature film was determined in axial and circumferential directions by measuring temperature gradients in the copper liner material. The experiments revealed remarkable circumferential differences of the film cooling efficiency which remain existent far downstream. However, circumferential film cooling varieties are more pronounced at close proximity of the point of film coolant injection.

Visualization of Coolant Liquid Film Dynamics in Hypergolic Bipropellant Thruster

“…Morrell [26] employed small rocket engines operating with three different coolant films: water, ethyl alcohol, and liquid ammonia. Arnold et al [27] experimentally measured temperature distribution of a LOX/liquid methane combustor and studied the film-cooling efficiency. These studies, however, focused on the film-cooling flow at the steady states, and there have been limited experimental data available reporting the developing film dynamics before reaching the steady film length.…”

Cars measurements at high pressure in a CH4/O2Jet flame

“…The present authors concentrated their e¨orts on simultaneous and synchronous CARS of H 2 and H 2 O because this gives valuable information on the mixing processes in the turbulent reacting §ow. H 2 and H 2 O were already widely used as probed molecules in the past for CARS temperature measurements in sub-and supercritical LOx/GH 2 cryogenic combustors because of their abundance [3,5,6]. In the current experiment, the same molecules were probed using a laser system composed of two separate optical benches producing the pump and Stokes beams required for H 2 and H 2 O Figure 5 The CARS experimental setup.…”

“…Among hydrocarbons, methane is one of the best suitable candidates because of its high speci¦c impulse. Moreover, it represents the simplest hydrocarbon fuel for investigating various physical processes related to rocket combustor technology such as regenerative cooling [3], kinetics of LOx/CH 4 [4], propellant injection [5], and ignition [6].…”

Experimental Investigation of Heat Transfer in a Subscale Liquid Rocket Engine

“…They are mainly based on calorimeter cooled segments where heat fluxes are deduced from enthalpy difference measurements of cooling channels. Such a setup was operated with methane and used for direct comparison with numerical simulations [9] and with both methane and hydrogen with specific focus on film cooling [10][11][12][13]. Ahn et al also used a calorimeter cooled combustion chamber to study the influence of bi-swirl injector recess length on the heat transfer at the wall for a multi-injector oxygen-kerosene configuration [14].…”