Application of a simulation algorithm to a specific liquid propellant engine with experimental verification

Abstract

Purpose -The purpose of this paper is to apply a new systematic simulation approach to an existing liquid propellant engine. Design/methodology/approach -The simulation approach is based on following the liquids (oxidizer and fuel) in their respective paths. The nonlinear dynamic model of the engine is composed of implicit nonlinear algebraic equations coupled with a set of differential equations. The model is solved by placing the implicit nonlinear algebraic equations in a set of nested Newton-Raphson loops followed by numerical integration of the differential equations using a first-order Euler technique. Findings -It is found that the simulation algorithm may successfully be applied to an operating point model to predict the steady-state values with errors under 10 percent. These results indicate that such engine models may be used to design reiable robust engine control systems because a robust control system design would allow for about 20 percent discrepancy between the model and the actual case. Research limitations/implications -At present, the research is limited to liquid propellant engines that are modeled by a set of implicit nonlinear algebraic equations coupled with a set of differential equations; engine models that are entirely modeled by differential equations are subject of future research. Practical implications -The major outcome of this research is that verifies liquid engines may be simulated by the novel idea of following the engine liquids in their respective paths. Originality/value -This is the first paper that adapts an existing simulation algorithm for simulation of the specific liquid engine under study with experimental verification.

Mathematical modeling and analysis of cutoff impulse in a liquid-propellant rocket engine

“…Experimental results have been obtained from a test a liquid-propellant engine and by data collection during the start, 30 operations, and at the time of sending the shutdown command. These data are associated with an open-cycle liquid-propellant engine with regenerative cooling (shown in Figure 2) and pyrotechnic valve (shown in Figure 3).…”

An algorithm on simultaneous optimization of performance and mass parameters of open-cycle liquid-propellant engine of launch vehicles

“…To obtain mass flow rate of the turbine, power of the pumps is calculated according to Equation 8 and Equation 9. In this study, the pumps' input pressure has been chosen as an algorithm input, where pox P  and pfu P  defined by Equation 10 and Equation 11, respectively, are the pressure difference of the pumps.…”

“…For specific amount of mass flow rate and chamber's pressure, the specific heat ratio and velocity of produced gas will be calculated. Therefore, the total mass flow rate of chamber, specific impulse and the produced thrust of the chamber can be derived from Equation 21 and Equation 22 [8,9], where  is the efficiency of nozzle that is usually taken to be around 0.9 to 0.98. …”

Modelling, simulation, and optimization of a hot pressurization system for a liquid propellant space engine and comparison with experimental results

“…Typical feed systems, which are usually considered in the literature, use a starter, a turbine, a turbopump system, regulators and stabilizers, pipes, and other simple hydraulic hardware. These types of systems have been extensively studied in the literature [1][2][3], and the interested reader is referred to these references for comprehensive modelling and simulation treatments.…”

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