Calibrating the Mixing Length Parameter for a Red Giant Envelope

Abstract

Two-dimensional hydrodynamical simulations were made to calibrate the mixing length parameter for modeling red giant's convective envelope. As was briefly reported in Asida & Tuchman (97), a comparison of simulations starting with models integrated with different values of the mixing length parameter, has been made. In this paper more results are presented, including tests of the spatial resolution and Large Eddy Simulation terms used by the numerical code. The consistent value of the mixing length parameter was found to be 1.4, for a red giant of mass 1.2 solar-mass, core mass of 0.96 solar-mass, luminosity of 200 solar-luminosities, and metallicity Z=0.001.