I am having some trouble modeling an internal fan simulation. I am simulating 4 fans running inside of a box. The fans are 38X38X25mm and run at 23CFM no load. The fans are placed in parallel inside the clube close to the front opening. I have an opening at both the front and the back of the cube where I have set the boundary conditions to ambient pressure (14.7psi). Inside of the cube I set up a internal fan condition for each of the 4 fans. I entered the fan profile from the manufacturer spec sheet. I then set a goal at the surfaces of the fan inlets and exists to determine the static pressure at the fan. I used 1 of these static pressure goals for convergence. After running my simulation I am finding that the pressure throughout my cube remains at ambient. All of my static pressure goals also display the ambiet pressure of 14.7psi. I am getting no pressure drop or rise anywhere in my model. This does not seem right to me. It is my belief that the fans should be causing a pressure differential. When I look at the flow of air, I see that the air does flow from the front of the cube to the back of the cube at a rate of 2m/s. Is there anyone out there who might be able to explain to me what is going on? I am unable to upload my model for NDA reasons.