Showing papers in "Journal of Rocket Propulsion in 2012"

Cold flow experimental research of RBCC ejector modal

Abstract: The method of cold flow experiment was used to research the anti-backpressure characteristics of RBCC ejector modal with different configurationsThe wall surface pressure curve in different length of the mixer and different configurations of main rockets is given by measuring the wall static pressureThe anti-backpressure performances of different configurations are analyzedThe Results show that the increase of the mixer length can improve the anti-backpressure performance,but the performance can not be improved significantly;the double main rockets structure can effectively enhance the anti-backpressure abilityThe test shows that the structure of main rocket has an important influence on anti-backpressure performanceThis test provides a reference for the configuration design of RBCC ejector modal

Simulation of dynamic regulating characteristics of PWM high-speed on-off valve

Abstract: For the pulse width modulation(PWM) high-speed on-off valve of a certain ramjet regulator,a simulation study on the system dynamic characteristics of pressure and flow rate during regulation of high-speed on-off valve was carried out by establishing a dynamic mathematical model of high-speed on-off valve system.The factors that influence the valve dynamic output characteristic were analyzed.The results indicate valve seat diameter,driving frequency and volume of control cavity are the main reasons that influence valve performance.The methods to improve the dynamic performance were provided.A reference is also provided for improving control system accuracy and performance in this paper.

Spectral-Fourier method for water hammer

Abstract: The mathematical model of fluid transient inside propellant pipelines is introducedA new algorithm is proposed to solve the nonlinear hyperbolic partial differential equations for gover-ning the fluid transient by spectral-Fourier methodThe method is presented in detail with an illustration of the water hammer in a simple piping system connecting tank and valveThe water hammer and pressure oscillation formed in the pipeline when its valve is suddenly shut down were solved with the methodThe corresponding simulation results are given and compared with the results obtained by method of characteristics and finite element method issued previouslyThe high frequency oscillation problem in the numerical calculation is also discussed

Improvement of static calibration method for pressure sensors

Abstract: The problems existing in the available calibration methods of pressure sensors used in the rocket engine test are analyzed in this paper.In order to solve these problems,an automatic static calibration method of the linear pressure sensor is proposed.This method can improve the calibration efficiency of pressure sensors and make up for the weakness of the current calibration methods by reducing the dependence on the accuracy of the pressure standard source and cycle times of the calibration.

Propane micro propulsion system used in micro and nano satellite

Abstract: A propane micro propulsion system used in a micro and nano satellite is introduced.With this system,the"liquid-gas"transformation was achieved without any extra consumption of energy on satellite by a heat exchange module.The propulsion system can realize a fast and accurate control for the thrust of 50 mN by the aid of pressure-stabilizing module and control module in the micro propulsion system.The dry mass of the system based on the miniaturization technology is only 2.5 kg.

Software architecture design of measurement and control system in ground testing system for large-scale rocket engine

Abstract: Through the status analysis of software development modes of ground testing and control system for the domestic large-scale rocket engines,the Rational Unified Process"4+1"view method is proposedThe modeling of measurement and control system software was carried out in combination with object-oriented design ideaA set of targeted object-oriented model of measurement and control system software design was buildIt laid a good foundation for solving the problems(low efficiency,high failure repeatability,difficult maintenance) generally existing in the software development of ground testing and monitoring system for large-scale rocket engines

Numerical simulation of soft metal sealing performance

Abstract: The soft metal sealing structure widely used in LOX/kerosene rocket engine was numerically simulated by means of the Nastran implicit nonlinear module and the method which combines the contact model and material elastic-plastic model.The relevant parameters such as structure stress,displacement,contact stress and so on are analyzed.The result shows that the intensity of the soft metal sealing structure can satisfy the requirement of application when it is at the pressure of 45 MPa,the contact stress of the sealing surface is above 300 MPa,and the sealing safety factor is more than 1.67.