Abstract: Disclosed herein in various embodiments are aryl-ether free polyaromatic polymers based on random copolymer architecture with two, three, or more aromatic ring components and methods of preparing those polymers. The polymers of the present disclosure can be used as ion exchange membranes, e.g., as anion exchange membranes, and ionomer binders in alkaline electrochemical devices.

Abstract: The present disclosure relates, in part, to polymers having a graft chain and/or a cyclic amino group. In particular examples, the graft chain and/or the cyclic amino group provides enhanced hydrophilicity, alkaline stability, and/or anion solvation. Compounds, compositions, and methods are described herein.

Abstract: A fuel supply system includes a fuel supply line, a fuel filter, a filter bypass line, a first differential pressure sensor, a second differential pressure sensor, and a filter bypass valve. The fuel filter is disposed in series in the fuel supply line to remove particulate from the fuel. The filter bypass line has a fuel inlet upstream of the fuel filter, and an outlet that is downstream of the fuel filter. The first differential pressure sensor continuously senses differential pressure across the fuel filter, and the second differential pressure sensor selectively senses differential pressure across the fuel filter. The filter bypass valve is movable between a first non-bypassing position and a second bypassing position and controls whether only the first differential pressure sensor or both the first and second differential pressure sensors sense the differential pressure across the fuel filter.

Abstract: A system provides “fail fixed” functionality and allows a user to manually manipulate fuel flow to a gas turbine engine in the unlikely event the primary control means is unavailable. The fuel metering unit includes a fuel metering valve, a flow increase valve, and a flow decrease valve. The flow increase valve and flow decrease valves are both in fluid communication with the fuel metering valve and are each adapted to selectively receive fuel flow commands from a primary fuel flow command source and from a secondary fuel flow command source. The flow increase and decrease valves are responsive to the fuel flow commands to selectively control the position of the fuel metering valve.

Abstract: A fuel supply system includes a fuel supply line, a fuel filter, a filter bypass line, a first differential pressure sensor, a second differential pressure sensor, and a filter bypass valve. The fuel filter is disposed in series in the fuel supply line to remove particulate from the fuel. The filter bypass line has a fuel inlet upstream of the fuel filter, and an outlet that is downstream of the fuel filter. The first differential pressure sensor continuously senses differential pressure across the fuel filter, and the second differential pressure sensor selectively senses differential pressure across the fuel filter. The filter bypass valve is movable between a first non-bypassing position and a second bypassing position and controls whether only the first differential pressure sensor or both the first and second differential pressure sensors sense the differential pressure across the fuel filter.

Abstract: A system provides “fail fixed” functionality and allows a user to manually manipulate fuel flow to a gas turbine engine in the unlikely event the primary control means is unavailable. The fuel metering unit includes a fuel metering valve, a flow increase valve, and a flow decrease valve. The flow increase valve and flow decrease valves are both in fluid communication with the fuel metering valve and are each adapted to selectively receive fuel flow commands from a primary fuel flow command source and from a secondary fuel flow command source. The flow increase and decrease valves are responsive to the fuel flow commands to selectively control the position of the fuel metering valve.

Abstract: A thermal recirculation throttle valve (1) for an aircraft fuel system includes a housing (11) having a throttling valve chamber; a cover (5) operatively engaging a first side of the housing (11); a power piston (6) within a power piston sleeve (7), the power piston (6) having a first (21) and second face (22) for control pressure to act upon, the power piston (6) and power piston sleeve (7) operatively engaged with the housing (11) within the throttling valve chamber; a Linear Variable Differential Transformer (15) for measuring a linear position of the power piston (6) within the housing (11); a throttling valve (8) within a throttling valve sleeve (9), the throttling valve (8) operatively engaged with the power piston (60) to transfer the linear movement of the piston (6) between a fully extended and a fully retracted operating position; and a flow deflector (10) engaged with the throttling valve (8) for protecting the housing (11) from flow erosion from fuel exiting flow windows (37).