Abstract: An example ullage-recirculating catalytic inerting system includes: (i) a plurality of fuel tanks having (a) respective inert gas ports for discharging the inert gas within a respective fuel tank, and (b) respective ullage gas ports for drawing ullage gas from the respective fuel tank; and (ii) an inert gas generating system including (a) an ullage gas inlet port fluidly coupled to the respective ullage gas ports, (b) an inert gas outlet port fluidly coupled to the respective inert gas ports, (c) a catalytic reactor for chemically converting ullage gas received through the ullage gas inlet port to inert gas for discharge through the inert gas outlet port, and (d) a prime mover for moving gas through the inert gas generating system.

Abstract: A catalytic inerting system (CIS) architecture includes a fuel tank including a fuel tank inlet and a fuel tank outlet, the fuel tank defining a space for containing a liquid fuel and an ullage space above the liquid fuel containing an ullage gas. A catalytic reactor is in fluid communication with the fuel tank, the catalytic reactor having a catalytic inlet and a catalytic outlet, wherein the catalytic reactor receives an ullage gas flow from the fuel tank outlet and performs a catalytic reaction on the ullage gas to produce a more inert flow from the catalytic outlet to the fuel tank inlet. A bypass line provides a flow pathway between the fuel tank inlet and the fuel tank outlet, thereby bypassing the fuel tank, and a flow control mechanism controls relative flows of the inert flow from the catalytic outlet to the fuel tank inlet versus through the bypass line.

Abstract: An example ullage-recirculating catalytic inerting system includes: (i) a plurality of fuel tanks having (a) respective inert gas ports for discharging the inert gas within a respective fuel tank, and (b) respective ullage gas ports for drawing ullage gas from the respective fuel tank; and (ii) an inert gas generating system including (a) an ullage gas inlet port fluidly coupled to the respective ullage gas ports, (b) an inert gas outlet port fluidly coupled to the respective inert gas ports, (c) a catalytic reactor for chemically converting ullage gas received through the ullage gas inlet port to inert gas for discharge through the inert gas outlet port, and (d) a prime mover for moving gas through the inert gas generating system.

Abstract: A catalytic inerting system (CIS) architecture includes a fuel tank including a fuel tank inlet and a fuel tank outlet, the fuel tank defining a space for containing a liquid fuel and an ullage space above the liquid fuel containing an ullage gas. A catalytic reactor is in fluid communication with the fuel tank, the catalytic reactor having a catalytic inlet and a catalytic outlet, wherein the catalytic reactor receives an ullage gas flow from the fuel tank outlet and performs a catalytic reaction on the ullage gas to produce a more inert flow from the catalytic outlet to the fuel tank inlet. A bypass line provides a flow pathway between the fuel tank inlet and the fuel tank outlet, thereby bypassing the fuel tank, and a flow control mechanism controls relative flows of the inert flow from the catalytic outlet to the fuel tank inlet versus through the bypass line.