variavel0=<b>Francisco F.S. Matos</b> - Francisco_F_Matos@embraco.com.br Empresa Brasileira de Compressores S/A
<b>Alvaro T. Prata</b> - prata@nrva.ufsc.br Universidade Federal de Santa Catarina
<b>Cesar J. Deschamps</b> - deschamps@nrva.ufsc.br Universidade Federal de Santa Catarina
<b>Abstract.</b> This work presents the modeling of automatic compressor valves under turbulent flow condition. The valve dynamics and the time dependent flow field are coupled and therefore solved simultaneously. A system with one-degree of freedom is adopted for the valve motion whereas the turbulent flow is solved with the RNG k- E model of Orzag et al. (1993), due to its capability to predict complex flow features such as those found in valves. In order to maintain the computational effort within available resources, the flow is considered to be incompressible, isothermal and axisymmetric. A numerical technique has been especially developed to take into account the time variation of the computational domain originated by the valve motion. Through a coordinate transformation a moving coordinate system is obtained so as to expand and contract according to the valve displacement. Results for flow quantities (streamline, turbulence intensity and length scale) and for the valve dynamics (resultant force and displacement) are obtained for a prescribed periodic mass flow rate at the valve entrance.
<b>Keywords.</b> Automatic valves, Compressor valves, Turbulence modeling.