Pump mixer separator unit

A fuel delivery system for an aeronautical engine, comprising:

• a supply portion comprising a stripping gas line that provides an inlet stripping gas flow, and a fuel line that provides an inlet fuel flow at a sub-ambient pressure;
• and
• a pump mixer separator unit comprising:
• a housing;
• a first inlet in the housing connected to the stripping gas line;
• a second inlet in the housing connected to the fuel line;
• a first outlet in the housing to provide an outlet fuel flow;
• and
• a second outlet in the housing to provide an outlet stripping gas flow,
• the housing containing a first pump and a second pump integral with the housing:
• the first pump in fluid communication with the stripping gas line and the fuel line to form a fuel/gas mixture flow, the first pump to draw in fuel at a sub-ambient pressure and generate a first pressure rise from the inlet fuel flow to the fuel/gas mixture flow;
• the second pump in fluid communication with the first pump, wherein the second pump receives the fuel/gas mixture flow from the first pump, wherein the second pump separates the fuel/gas mixture flow into the outlet stripping gas flow and the outlet fuel flow and generates a second pressure rise from the fuel/gas mixture flow to the outlet fuel flow;
• and
• a recirculation stripping gas flow loop in fluid communication with the second pump and the stripping gas line, the recirculation stripping gas flow loop configured to:
• receive the outlet stripping gas flow from the second pump, reduce an oxygen content of the received outlet stripping gas flow, and provide the received the outlet stripping gas flow having the reduced oxygen content to the stripping gas line,
• wherein the first pump includes a supplemental pump feature for drawing the inlet fuel flow through the fuel line through suction at the sub-ambient pressure during operation,
• the first pump further including an axial impeller and a first radial impeller, the second pump including a second radial impeller, the axial impeller to draw the inlet fuel flow in conjunction with the supplemental pump feature via the fuel line and generate the first pressure rise, an output of the axial impeller connected to an input of the first radial impeller, the axial impeller to provide the inlet fuel flow to the first radial impeller, the first radial impeller to mix the inlet fuel flow with the inlet stripping gas flow from the stripping gas line to form the fuel/gas mixture flow, the first radial impeller to output the fuel/gas mixture flow to the second radial impeller, the second radial impeller separating the fuel/gas mixture flow into the outlet stripping gas flow and the outlet fuel flow and generating the second pressure rise.