Current global concerns on environmental protection and sustainable development for clean energy have led to the creation of new engineering devices. Since the dimensions and geometry of the microchannel and the fluid (gas-liquid) used in each phase flow can have an effect on system performance, in this study consists of three parts to compare several different modes using simulation has been numerically. First a two-dimensional simulation of different T-shaped microchannel and two-phase steady flow (gas-liquid) with different fluids and multiphase flow with Eulerian model has been performed. Then different fluid is used in simulations of two-dimensional two-phase flow and heat transfer system to investigate the microchannel performance in cooling. Finally pressure drop and heat transfer coefficient of fluid inside the T-shape has been calculated in two-phase flow.