By maens of or thogonal experiments

the flowability of Al-Li alloy in graphit moldunder vaccum condition is measured

the principal influencing factors are obtained.Based on Benulli equation and energy equation

the vilocity

temperature field and the flowing lenth of Al-Lialloy filling in bar-shape are simulated with computer. Using Volume of Fluid（VOF）method

combining the fluid flow and heat transfer

the computor simulates not only the two dementionalvelocity field and temeprature field

but also the flowing stoping process

providing the theory ofpredicting and preventing defacts such as shot run

cold shut and so on.