wanted udf programm
 

hi..my name is chandu..me and my friend jignesh are working in mixing flows .we r stuck with u.d.f..we want pressure boundary condition udf.in which the prssure is function of time...the function is a step function..can anybody give udf to us...urgent..please help...and we r also getting this error when we are doing unsteady simulations "Specific_Heat_by_T_Integral: invalid lower bound, T0 <= 0".