Thermal management system with fuel cooling

A method of operating a system, the method comprising:

• flowing a coolant along a coolant flowpath, the coolant flowpath including a cooling system such that the coolant passes through the cooling system to cool the coolant, the coolant flowpath further including a coolant-cooled thermal load Lfuel;
• flowing a fuel along a fuel flowpath, the fuel flowpath including a fuel tank for accumulating the fuel and a fuel-cooled thermal load Lfuel;
• passing both the coolant and the fuel through a coolant-fuel heat exchanger to cool the fuel;
• controlling the flow of the fuel from the coolant-fuel heat exchanger to the fuel tank for accumulation of the cooled fuel;
• and
• controlling the flow of the fuel from the coolant-fuel heat exchanger to a fuel use location,
• wherein the coolant has a thermal capacity TCcool and the fuel has a thermal capacity TCfuel,
• wherein the flow of the fuel includes a flow Ftank of the fuel to the fuel tank and a flow Fuse of the fuel to the fuel use location, and
• wherein the flow of the fuel is controlled such that Ftank/Fuse>1 when TCcool>Lcool.

A method of operating a system, the method comprising:

• flowing a coolant along a coolant flowpath, the coolant flowpath including a cooling system such that the coolant passes through the cooling system to cool the coolant, the coolant flowpath further including a coolant-cooled thermal load Lcool;
• flowing a fuel along a fuel flowpath, the fuel flowpath including a fuel tank for accumulating the fuel and a fuel-cooled thermal load Lfuel;
• passing both the coolant and the fuel through a coolant-fuel heat exchanger to cool the fuel;
• controlling the flow of the fuel from the coolant-fuel heat exchanger to the fuel tank for accumulation of the cooled fuel;
• and
• controlling the flow of the fuel from the coolant-fuel heat exchanger to a fuel use location,
• wherein the coolant has a thermal capacity TCcool and the fuel has a thermal capacity TCfuel,
• wherein the flow of the fuel includes a flow Ftank of the fuel to the fuel tank and a flow Fuse of the fuel to the fuel use location, and
• wherein the flow of the fuel is controlled such that Ftank/Fuse<−0.50 when Lfuel>TCfuel.

A system, comprising:

• a coolant flowpath containing a coolant having a thermal capacity TCcool, the coolant flowpath including a cooling system configured to cool the coolant and a coolant-cooled thermal load Lcool;
• a fuel flowpath containing a fuel having a thermal capacity TCfuel, the fuel flowpath including a fuel tank for accumulating the fuel and a fuel-cooled thermal load Lfuel;
• a coolant-fuel heat exchanger in thermal communication with the fuel and coolant such that heat flows from the fuel to the coolant to cool the fuel;
• and
• one or more valves automatically actuated by a change in temperature, a change in pressure, or a change in both temperature and pressure to control a flow Ftank of the fuel from the coolant-fuel heat exchanger to the fuel tank for accumulation of the cooled fuel and a flow Fuse of the fuel to a fuel use location such that Ftank/Fuse>1 when TCcool>Lcool and Ftank/Fuse<−0.50 when Lfuel>TCfuel.