Thermodynamic Modeling of a Rotating Detonation Engine
49th AIAA Aerospace Sciences Meeting including the New Horizons Forum and Aerospace Exposition
In pursuit of greater thermal and propulsive efficiencies in rockets or gas turbines, a onedimensional thermodynamic model of a Rotating Detonation Engine (RDE) is compared to a numerical simulation model with good results. A ZND detonation model is modified to include stagnation properties and account for the velocity vectors that occur upstream of the detonation. Features of the RDE and their impact on the model are discussed. Velocity triangles, commonly used in the gas turbine industry, are
... rbine industry, are shown to be an effective tool for understanding energy transfer in RDE's. 2 Understanding the operation of a RDE requires a basic thermodynamic model. The requirements for this model are driven by its suitability as an initial analysis tool of a RDE in much the same way that a Brayton cycle model is used for preliminary analysis of gas turbines. The model must be one-dimensional and independent of flow geometry. There must be means to account for the first order effects of thermodynamic states and an accounting of loss mechanisms. An assessment of efficiency and performance must be made with a reasonable degree of fidelity. Common thermodynamic equations of state should be used and the chemistry of combustion should be manifest only as heat added and appropriate gas constants. Above all, the model must be understandable at a fundamental level. A thermodynamic assessment is made of a rotating detonation wave engine for the purpose of creating a parametric model. This model is based on a ZND (Zeldovitch-von Neumann-Doring) 6 analysis modified by the use of the Rankine-Hugoniot equations and the application of a vector analysis of the upstream conditions. This model is compared to the thermodynamic cycle based on data from a computational simulation of an RDE. With some adjustments, the modified ZND model approximates many features of the computational model. Further refinements should improve the predictability of the model. This model provides a reasoned thermodynamic basis for theoretical understanding, design and testing of RDE's.