Hello: I am trying to model GDI engine using star 3150 A. Can any body suggest me how to do the set-up. The help or tutorial files does not have an example for it. i wld really appreciate if some body cld suggest me steps to set it up.

Well, first you need to create a grid considering your combustion chamber geometry. Then you set Analysis Features (Transient, Steady), Lagrangian Multi-Phase, Chemical Reaction, usually if you run spray and combustion model it will be transient. Then you go to Thermophysical Models and Properties and set up molecular properties for air, then you set up turbulence model, thermal model, initialization for air, monitoring and reference data. Then you need to set chemical reactions (Scheme Definition, Reaction system, Ignition, Emission, Scheme Association, etc., Additional Scalars. Then you go to Lagrangiam Multi-Phase and specify droplet properties. Then you go to analysis controls -> solution controls -> Equation Behavior -> primary variables -> Solver Parameters. You also need to set additional scalars. Then you go to Analysis output and specify the time per period and you select the data to be written by STAR. Then you go to Set Run Time Controls and specify total run time for your model, as well as, time step for period. Then you save a geometry file, a problem file and run STAR.