Mathematical Modelling and Dynamic Analysis of a Direct-Acting Relief Valve Based on Fluid-Structure Coupling Analysis

Table 1

List of system parameters.

Parameters	Signs	Units	Values
Rod body’s total mass		kg	13.7e−3
Oriented seat’s spring stiffness		N/m	1.266e5
Spring precompression		m	2.227e−3
Overflow amount		m^3/s	7.67e−5
Density of water		kg/m^3	1000
Density of fuel		kg/m^3	1232
Pump inlet pressure		Pa	0.4e6∼0.8e6
Pump outlet pressure		Pa	10e6
Radius of back pressure ejector pins		m	3.0e−3
Radius of ball valve		m	2.3812e−3
Radius of valve seat channel		m	2.2e−3
Radius of pump inlet		m	8e−3
Atmospheric pressure		Pa	1e5
Washer’s damping			30
Vertical vibration damping of the rod string			30
Fluid damping		1	0.9
Vertical stiffness of the rod string		N/m	1e6
Fluid compression modulus		Pa	5e9
Pore throat’s fluid volume		m^3	1.1404e−7
Fluid resistance coefficient		1	1.0
Fluid lift coefficient		1	0.2
Added mass coefficients		1	1.0
Strouhal number		1	0.15∼0.2
Restitution coefficient of impact		1	0.2∼0.4