[bsantana]

Hi:
I am currently "learning" and using the COMSOL Fluids module to analyze an 2D (for the moment) intake manifold geometry, for an undergraduate research course. The geometry has a 20mm inlet, 1.5 inch outlets and 6 inch cylindrical plenum. After performing the simulations it seems like the vacuum force from the piston the intake phase is missing (it rather seems like if i was just blowing air from the inlet, like if i was blowing air through a seashell) I tried establishing the outlets boundary condition to decreasing pressure values until i reached negative pressure values, [but with these (negative values) i had an error during the simulation]. An early hypothesis could be that, the velocity is inversely proportional to the area in order the achieve the mass conservation condition. However, i tried reducing the plenum diameter to decrease abrupt change in plenum area and try to maintain more constant velocity values, but this netted unsuccessful results. Any help or input would be greatly appreciated as i am running out of time. If this is the wrong forum, admins, feel free to move or relocate. Attached is a result of one of the simulations.