1 Reply Latest reply on Feb 21, 2013 4:57 PM by Jared Conway

    Why does time dependent(transient) simulation of fsae intake manifold result in flow in only two runners?

    Samio Roi

      Hii All,

      I was doing a time dependent flow simulation for our manifold. The inlet was set to ambient pressure. The runners were given a data in which the data upper time limit was
      0.01365, with steps of 0.000525. The time dependency had a phase difference of 90 deg every cylinder. After running the simulation, I explored the results through a flow trajectory which shows the fluid flow only in 2 of the runners.

      It would be great if anyone could help me figure out what else have i left out (like some goal is to be defined). Also the maximum calculation time was set to .017 sec.

       

      Any help is greatly appreciated.

      Thanks,

      Samio

        • Re: Why does time dependent(transient) simulation of fsae intake manifold result in flow in only two runners?
          Jared Conway

          what is the boundary condition at the end of each runner? pressure or volume flow rate? and just to confirm, you're "turning" them on and off in phase to simulate the effect of the cylinders? if you have them all open, you'll have to elaborate on how what you're trying to analyze.

           

          what does a surface parameter of volume flow rate or pressure over time look like at each of the runner outlets? that would tell you if your boundary conditions are working properly.

           

          what was the finishing condition that stopped your calculations? did it reach all the way to your max time?

           

          sorry for all the questions, but when you plotted the flow trajectory, were you looking at a specific time step? if you were, you're probably only seeing what is happening with that time step vs what is happening "over time". IE, if you're turning the cylinders on and off in phase, you're only seeing what happens at one time step.