The presence of free gas at the pump intake and in the discharge tubing makes the process of equipment selection much more complicated and voluminous. As the fluid (liquid and gas mixture) flows through the pump stages from intake to the discharge and through the discharge tubing, the pressure fluid properties (such as volume, density, etc.) continue to change. The presence of free gas in the discharge tubing may create significant “gas-lift” effects would could considerably reduce the required discharge pressure.