Numerical Study of Heat Transfer in Film Cooled Thrust Chambers

Abstract

Film cooling as a thermal protection for the walls of liquid rocket engines is studied numerically for hydrogen and methane thrust chamber tests. The aim is to verify the capability of the Reynolds Average Navier-Stokes model to capture the basic characteristics of film-cooled thrust chambers, considering a simplified approach, named pseudo-injector approach, which does not model propellant injection and combustion. This assumption allows a great saving in computational time, in particular when considering 3D simulations. The present study takes its origin from the European Community In-Space Propulsion 1 (ISP-1) program where, among various projects, an experimental campaign has been designed to study the film cooling technique in an oxygen/methane thrust chamber and to provide a database for computational fluid dynamics validation. The results show that the present approach gives good results in terms of heat flux characterization, in particular when dealing with test cases of high chamber pressure.

Numerical and experimental investigation of the methane film cooling in subscale combustion chamber

“…To realize the validation of combustion pressure distributions in the combustion chamber, one cannot use the combustion gas instead Figure 6 Averaged heat §ux in circumferential direction: (a) 0.46-millimeter slot; (b) 1.00-millimeter slot dimension; and (c) no ¦lm cooling. Signs refer to experiments and curves to CFD of the actual coaxial injector con¦guration, which was proposed in the previous works [5,6]. Figure 6 shows the circumferentially averaged heat §uxes for the experiment and simulation.…”

“…In the previous numerical works [5,6], the coaxial injector of CH 4 and O 2 was simpli¦ed to simulate the heat §ux to the thrust chamber wall of the CH 4 /O 2 subscale combustor. The near injector plate phenomena were neglected, and equilibrium combustion products were injected into the chamber at the adiabatic §ame temperature.…”

Coupled Heat Transfer Analysis in Regeneratively Cooled Thrust Chambers

“…Wall heat flux evaluation has been validated by reproducing a benchmark test case involving a supersonic nozzle operated with air. 16 B. Coolant and wall: quasi-2D solver A simplified quasi-2D approach 7 is used to study the coupled problem of coolant flow and wall structure heat transfer in rectangular cooling channels of liquid rocket engine thrust chambers. The cooling channel flow model is developed by using the steady-state conservation laws of mass, momentum, and energy, taking into account the effects of heat transfer and friction.…”

“…In particular, combustion is not simulated, but a flow of combustion products in chemical equilibrium at the chamber temperature and pressure is injected using a "full-inlet" approach. 16 The numerical solutions are carried out by means of an in-house 3D multi-block finite volume RANS equations solver able to treat multi-component mixtures of thermally perfect gases. Multicomponent diffusion has been validated 17 reproducing experimental test cases retrieved in open literature.…”

Development of Thrust Chamber Components for a System Analysis Tool

“…Turbulence is described by means of the Spalart-Allmaras one-equation model [28], a constant turbulent Schmidt number is adopted to model turbulent diffusivity, and a constant turbulent Prandtl number is adopted to model turbulent conductivity. The present solver has been validated in different operative conditions against experimental data [29][30][31]. Frozen flow assumption is adopted without aiming to describe the details of injection and combustion of propellants in the thrust chamber.…”