【摘要】 在对机械液压系统建模和仿真的过程中,液体密度和体积弹性系数的选取将直接影响到模型的精度.国内通常采用的方法是根据工程经验对其取常数,建模精度低.本文研究了如何选取这两个参数的方法,总结了这些参数的简化计算公式和算法,并运用该方法进行实例计算.结果表明:正压阶段,压力对于密度和体积弹性系数的影响很小,而当压力为负压时,必须考虑油液气体含量及压力等因素对于两者的影响.更多还原

【Abstract】 During the process of modeling and simulation for hydromechanical systems,the model precision can be affected directly by the choice of liquid density and fluid bulk modulus. The traditional method,in which these two parameters are taken as constants based on engineering experience,often lowers the modeling precision. A new method to calculate the liquid density and the fluid bulk modulus has been proposed in this paper,and the formula and algorithm for simplifying these parameters are summarized. A case widely used in the aerospace systems is thoroughly explained with this method. Results indicate that the pressure in positive stage has a little effect on the liquid density and fluid bulk modulus,whereas it must be taken the influence of gas content and pressure on these parameters into account during the stage of negative pressure.更多还原