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Under Properties, ensure that density is set to Constant and enter 1 kg/m^3
as the density. Click Change/Create to set the density. Now that the fluid has been described, we are ready to set the boundary conditions of the simulation. Bring up the boundary conditions menu by selecting Problem Setup > Boundary Conditions. In the Boundary Conditions window, look under Zones. First, let's set the boundary conditions for the inlet. Select Inlet to see the details of the boundary condition. The boundary condition type should have defaulted to velocity-inlet: if it didn't, select it. Now, click Edit to bring up the Velocity-Inlet Window. We need to specify the magnitude and direction of the velocity. Select Velocity Specification Method > Components. Specify X-Velocity as 1 m/s
and Y-Velocity{*}{*} as 0 m/s