Numerical analysis of the fluid-structure interaction in the pulsating flow through a radial diffuser

• Grant number: 13/04231-7
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: May 01, 2013
• End date: August 31, 2015
• Field of knowledge: Engineering - Mechanical Engineering - Thermal Engineering
• Principal Investigator: José Luiz Gasche
• Grantee: Iago Lessa de Oliveira
• Host Institution: Faculdade de Engenharia (FEIS). Universidade Estadual Paulista (UNESP). Campus de Ilha Solteira. Ilha Solteira , SP, Brazil

Abstract

Hermetic reciprocating compressors are widely used in small and medium-size vapor compression refrigeration systems. One of the main parts of this type of compressor is the automatic valve system used for controlling the suction and discharge processes. The experimental or analytical/numerical study of these processes is very complex, mainly because the occurrence of the fluid-structure interaction problem during the operation of the valves and due to the geometric complexity of the whole system. Thus, simplified models as radial diffusers have been used to represent the valve system. This work consists of a numerical investigation of the fluid-structure interaction problem in pulsating flows through a radial diffuser with a diameter ratio of 1.2, in which the frontal disc moves due to the flow forces and the restitution force of a spring connected in the frontal disc. The commercial code Ansys-Fluent will be used for the numerical solution of the flow, considering average Reynolds numbers in the range of 3000 and 20000. After validating the numerical procedure, the behavior of the effective force area and discharge coefficient, which are lumped parameters very used for designing compressor valves, will be investigated. (AU)