Effect of piston texture at inclination and eccentricity work conditions on damping characteristics of a hydraulic shock absorber

Abstract

In order to accurately predict the damping characteristics of a hydraulic shock absorber under piston inclination and eccentricity conditions, especially, considering effects of piston surface construction. In present work, taking account of piston slight inclination and eccentricity, a more detailed mathematical model was developed to estimate effects of piston texture on damping characteristics. Based on the mathematical models of reservoir and compression stroke coupled with Reynolds equation, a new damping force model was developed, which analyzed effects of piston structure on damping characteristics. The mathematical models of piston texture, piston slight inclination, piston eccentricity and combinations of three cases are developed to analyzed in detailed effects of piston texture at different work conditions on damping characteristics. The results shown that the friction force of piston increases parabolically with increasing depth ratio, and that of piston increases linearly with increasing area ratio. Piston textures have little effects on damping characteristics at specific structural parameters conditions when piston normal operation, however, textures of slight inclined and eccentric piston have great effects. As a result, piston textures might cause high damping force, destroyed comfort and safety. Therefore, it is necessary that effects of piston surface construction were precisely predicted on damping characteristics under different work conditions. The results might provide a new insight for the design of hydraulic shock absorber and investigation of vehicle system dynamics.

Assessment of a hydraulic bottle jack as an effective device for controlling vibration and mitigating the effects of earthquakes

“…44 Their principal elements include a pumping mechanism, oil, and valves: the pumping mechanism supplies energy to the system, while the valves control the oil flow and pressure, 45,46 and the oil lubricates the internal parts and transmits the pressure imposed by the pump to the lifting chamber. 47 The pressure created in this way represents the reaction of the system to the applied (or sustained) force. However, precise control over the pressure level has been a recurring challenge for manufacturers 48 aiming to establish reliability and good operating conditions.…”

Comparative study of a hydraulic, pneumatic and electric linear actuator system

“…Their precision and control make them suitable for applications where precise and repeatable motion is required 10,12 . Hydraulic 2,6,8, [13][14][15][16][17][18][19][20][21][22][23] and pneumatic 10,11,21,[24][25][26] systems are quite easy to compare, since both systems convert the energy stored in the uid into mechanical energy (force or torque), and the working principle is almost identical. The only difference is that the most common hydraulic systems usually use oil as the uid, while pneumatic systems use air.…”

Comparison of hydraulic, pneumatic and electric linear actuation systems

“…Their precision and control make them suitable for applications where precise and repeatable movement is required 20,22 . Hydraulic 2,6,14,16,18,[23][24][25][26][27][28][29][30][31][32][33] and pneumatic 20,21,26,[33][34][35][36] systems are quite easy to compare because both systems convert the energy stored in the fluid into mechanical energy (force or torque) and the principle of operation is almost identical. The only difference is that the most common hydraulic systems usually use oil as the fluid,…”