Parameter Analysis of Spherical Pulsation Damper Using ANSYS Fluid-Solid Interaction

Abstract

Abstract Various devices have been developed for the reduction of pulsation-induced vibrations, such as diaphragm chamber systems or gas bladders, non-intrusive fluid wave actuators and fluid filled, also known as reflection-type, dampeners. However, these devices are not suitable in a hydraulic system powered by a triplet piston pump. For example, pulsation dampeners incorporating gas bladders are effective, but there are many drawbacks. Loss of gas charge, incorrect gas charge or volume/mass ratio, elastomeric rupture, narrow range of pressure operation and pump speeds, routine maintenance, ineffective location, and branch connection instead of in-line configuration are all integrity issues which the industry faces. In addition to having a structural integrity issue, branch connected devices do not perform as efficiently as in-line devices. If a pulsation dampener is responsible for safeguarding critical equipment or systems, premature rupture of a gas bladder can be catastrophic. This paper introduces a spherical pulsation dampener which is used to reduce harmful pulsations induced by a triplet piston pump in fluid power systems. The damper is composed of an inlet, a distributing plate with nozzles, a spherical housing, a receiving plate with orifices, and an outlet. The damper can be welded in-line and reduce 75% of pulsation-induced vibrations. The paper presents how fluid-solid interaction (FSI) and transient structural modules of ANSYS will be used to model and simulate the spherical pulsation damper. Developing a compatible system coupling module is necessary to generate models cognizant of time and computing expenditure. The preparatory build model is used to study mechanisms of pulsation reduction in the spherical damper and to analyze the correspondence of key damper parameters to the effectiveness of pulsation reduction. A CAD model of the pulsation damper is built in Autodesk Inventor, with a control volume of the fluid in the damper indicative of proper boundary condition. The model will then be imported into ANSYS, with fluid-solid interaction and transient structural modules, to study fluid flow fields and understand the governing mechanisms for reducing the pulsation induced by a triplet piston pump. Furthermore, a study will be carried out to analyze how the design of key parameters, such as the diameters of the inlet and the outlet nozzles, the axial distance between the distribution plate and the receiving plate, and the radius of the spherical housing, experience fundamental repercussions in pulsation reduction. The results of this work will be partially useful for engineers to design an efficient spherical pulsation damper, and supplement individual requirements to match up a triplet piston pump with a spherical pulsation damper effectively.