# Result Table - Rotating Positive Displacement Pump

The available results that are listed in the table vary depending upon the visible properties that you have selected. Figure 1 shows the normal or default rows. You can choose the rows you wish to display in the results table via the Set Visible Results Dialog. Figure 1: Available results for a rotary PD pump. Only descriptions for the default results are shown in this section. If you wish to see the definition for other values click here. -- ID -- (aka User Number): All flowsheet elements have a unique number that is assigned by FluidFlow. It is not possible for the user to change this number because it is used as a unique identifier by the scripting module. Node numbering starts from 1, incrementing upwards, and pipe numbering starts from -1, decrementing downwards. Composition Mass %: This is the fluid mass composition that remains constant throughout the pump. FluidFlow determines the composition because an individual component mass balance is carried out at each node. Duty Flow: This is the flow that FluidFlow has calculated that the pump will deliver when it is placed in your system. For a rotary positive displacement pump this will be equal to the operating speed x the volume displacement per revolution less any slip. The slip through the pump is a function of liquid viscosity Duty Pressure Rise: This is the head that will be developed by a rotary positive displacement pump at the duty flow. A rotary positive displacement pump, in any fixed system will always deliver the head required to overcome system friction and static head differences, whatever the pressure requirement. In Stagnation Pressure: The stagnation pressure at the pump inlet. This is the sum of kinetic and pressure energies (static pressure + velocity pressure). Stagnation pressure is the pressure a flowing fluid would rise to if brought isentropically to rest, converting its kinetic energy to enthalpy. In Stag. Temperature: This is the stagnation temperature at the pump inlet. The stagnation temperature is the temperature that the fluid would reach if it were brought to rest isentropically, converting its kinetic energy to enthalpy. In Static Pressure: This is the pressure that acts equally in all directions at the point in the fluid and is present irrespective if the fluid is flowing or if the fluid is at rest. The pressure inside any element is not the static pressure, unless there is no flow. Stagnation pressure is the flowing pressure. In Static Temperature: The static temperature at the element inlet. Static temperature is related to stagnation temperature (ignoring work, heat exchange, and potential energy) by the equation T 1 = T 1 0 - 0.5 v 1 2 / C p In Velocity: The velocity at the pump inlet. This is often different to the outlet velocity because typically pump suction size is larger than pump discharge size. Out Stagnation Pressure: The stagnation pressure at the pump outlet. This is the sum of kinetic and pressure energies (static pressure + velocity pressure). Stagnation pressure is the pressure a flowing fluid would rise to if brought isentropically to rest, converting its kinetic energy to enthalpy. Out Stag. Temperature: This is the stagnation temperature at the pump outlet. The stagnation temperature is the temperature that the fluid would reach if it were brought to rest isentropically, converting its kinetic energy to enthalpy. Out Static Pressure: This is the pressure that acts equally in all directions at the point in the fluid and is present irrespective if the fluid is flowing or if the fluid is at rest. The pressure inside an element is not the static pressure, unless there is no flow. Stagnation pressure is the flowing pressure. Out Static Temperature: The static temperature at the element outlet. Static temperature is related to stagnation temperature (ignoring work, heat exchange, and potential energy) by the equation T 2 = T 2 0 - 0.5 v 2 2 / C p Out Velocity: The velocity at the pump outlet. Volumetric Efficiency: This is a volumetric efficiency of the rotary positive displacement pump at the duty point. In this sense, it represents a measure of the slip back of liquid through the pump.