RPA: Tool for Rocket Propulsion Analysis Assessment of Delivered Performance of Thrust Chamber Alexander Ponomarenko
[email protected] http://www.propulsion-analysis.com March 2013 (v.1) Abstract Rocket Propulsion Analysis (RPA) is a multi-platform analysis tool intended for use in conceptual and preliminary design (design phases 0/A/B1). This report describes a numerical models and computation techniques implemented in RPA to estimate the delivered performance of thrust chambers. Contents Nomenclature..........................................................................................................................3 Introduction.............................................................................................................................4 Numerical Model.....................................................................................................................4 Delivered Performance.......................................................................................................4 Correction Factors..............................................................................................................6 Finite Rate Kinetics in the Combustion Chamber..........................................................6 Boundary Layer (Friction) Loss......................................................................................7 Divergence Loss...........................................................................................................10 Multi-Phase Flow Loss.................................................................................................12 Built-In Assessment..........................................................................................................13 Finite Rate Kinetics in the Nozzle................................................................................13 Finite-Area Combustion Chamber................................................................................13 Interzonal Losses.........................................................................................................15 Nozzle Flow Separation...............................................................................................16 Thrust Throttling ..........................................................................................................17 Application in RPA and RPA SDK.........................................................................................19 References............................................................................................................................20 2 Nomenclature A cross-sectional area, m2 ̄ A ̄ = A / At relative cross-sectional area, A ̄ F ̄ =A / m˙ , (s·m2)/kg specific cross-sectional area, F c* characteristic velocity, m/s Is specific impulse, m/s Cf thrust coefficient p pressure, Pa T temperature, K w velocity, m/s M Mach number λ characteristic Mach number density, kg/m3 m˙ mass flow rate, kg/s Re Reynolds number δ** boundary layer momentum thickness η dynamic viscosity, kg/(m·s) ξ