Aerothermal Prediction of an Aeronautical Combustion Chamber Based on the Coupling of Large Eddy Simulation, Solid Conduction and Radiation Solvers

Abstract

A precise knowledge of the thermal environment is essential for gas turbines design. Combustion chamber walls in particular are subject to strong thermal constraints. It is thus essential for designers to characterize accurately the local thermal state of such devices. Today, the determination of wall temperatures is performed experimentally by complex thermocolor tests. To limit such expensive experiments and integrate the knowledge of the thermal environment earlier in the design process, efforts are currently performed to provide high fidelity numerical tools able to predict the combustion chamber walls temperature. Many coupled physical phenomena are involved: turbulent combustion, convection and mixing of hot products and cold flows, conduction in the solid parts as well as gas to gas, gas to wall and wall to wall radiative transfers. The resolution of such a multiphysics problem jointly in the fluid and the solid domains can be done numerically through the use of several dedicated numerical and algorithmic approaches. In this paper, a partitioned coupling methodology is used to investigate the solid steady state wall temperature of a helicopter combustor in take-off conditions. The methodology relies on a high fidelity Large Eddy Simulation reacting flow solver coupled to conduction and radiative solvers. Different computations are presented in order to assess the role of each heat transfer process in the temperature field. A conjugate heat transfer simulation is first proposed and compared with experimental thermocolor tests. The effect of radiation is then investigated comparing relative importance of convective and radiative heat fluxes.

Joint experimental and numerical study of the influence of flame holder temperature on the stabilization of a laminar methane flame on a cylinder

“…Note that computing the interaction between the flame and the wall requires to compute both the flow and the temperature within the walls simultaneously: the LES code must be coupled with a heat transfer code within the combustor walls. This task is not simple [19,20] because time scales are usually very different (a few milliseconds in the flow and a few minutes in the walls).…”

Prediction of Liner Metal Temperature of an Aeroengine Combustor with Multi-Physics Scale-Resolving CFD

“…Therefore, to effectively handle this problem and reduce computational costs, a loosely coupling is preferred, where segregated simulation processes are adopted for each involved physics (i.e., flow field, radiation, and heat conduction) exchanging only the relevant quantities among domains at a given frequency. The open literature reports several approaches suitable for the analysis of long transients [ 19 , 20 ] or quasi-steady [ 21 , 22 , 23 ] metal temperature evolution.…”

Multiphysics Numerical Investigation of an Aeronautical Lean Burn Combustor

“…On the other hand, in order to effectively overcome this issue and minimize the CPU cost, loose coupling is preferred where different simulations are devoted to each physics exchanging only some quantities at a given frequency at the interface between two coupled domains. Several approaches can be found in literature, suitable for the prediction of long transient [19,20] or quasi-steady [21][22][23] metal temperature.…”