Second Order Polynomial Model for Fluid Dynamics in High Pressure

This paper suggests second order polynomials for modeling hydraulic fluid dynamic properties — tangent bulk modulus, density and speed of sound in fluid. Model parameters can be calculated from ISO fluid characteristics data available for every commercial hydraulic fluid. The accuracy of the models is verified with measurements at pressures up to 1500 bar. The measurement results as well as the measuring method are also introduced. Although the models are quite simple, correlation with the measurement results is excellent.