porous jump boundary jump thread not handled
 

hi friends, iam trying to simulate flow in a channel, tha channel has a valve, regulating the flow by maintaing the presseure drop across the valve. To simulate for the pressure drop across the valve, iam trying to use Fan boundary condition or Porous jump boundary condition. When i initialize the problem in Fluent, it is showing that "JUMP THREAD NOT HANDLED", i dont know wht this error is all abt. please can any one help me, Thanks a lot