Liquid cooled electronic chassis having a plurality of phase change material reservoirs
A system and method of thermal management of electrical and electronic systems and components that adequately maintains the temperatures of the system electronics and electrical devices within reliable limits during various postulated system malfunctions. The system and method use a phase change material (PCM). In at least some embodiments, the PCM is disposed such that, if a flow of coolant ceases when primary and backup control circuits are energized, primary control circuit temperature will exceed a predetermined temperature within a first time period after the flow of coolant ceases, and backup control circuit temperature will exceed the predetermined temperature a second time period, which is greater than the first time period, after the flow of coolant ceases.
1. An electronic chassis cooling system, comprising:
a chassis having a plurality of electrical devices mounted therein that are thermally coupled to the chassis, the electrical devices operable, when energized, to generate heat;
a plurality of heat sink devices coupled between the electrical devices and the chassis, to thereby thermally couple the electrical devices to the chassis;
a plurality of reservoirs formed in the chassis;
a phase change material (PCM), disposed within each of the reservoirs, that changes phase from a first phase to a second phase at a phase-change temperature;
a coolant flow passage formed in the chassis and coupled to receive a flow of coolant; and
a coolant supply system operable to supply the flow of coolant into and through the coolant flow passage at a flow rate that, at least when the electrical devices are energized, is sufficient to:
(i) remove at least a portion of the generated heat, and
(ii) maintain the PCM below the phase-change temperature.
2. The system of claim 1 , wherein the coolant supply system comprises:
a coolant reservoir having a volume of coolant disposed therein; and
a coolant pump having an inlet and an outlet in fluid communication with the coolant reservoir and operable to supply to the flow of coolant to the coolant flow passage.
3. The system of claim 1 , wherein the chassis comprises a cold plate having the plurality of reservoirs and the coolant flow passage formed therein.
4. The system of claim 3 , wherein the cold plate is disposed to transfer heat from a surrounding environment to the coolant.
5. The system of claim 1 , wherein:
the plurality of electrical devices comprise at least a primary control circuit and a backup control circuit; and
the reservoirs, and the PCM disposed therein, are formed in the chassis such that, if the flow of coolant ceases when at least the primary and backup control circuits are energized,:
primary control circuit temperature will exceed a predetermined temperature within a first time period after the flow of coolant ceases,
backup control circuit temperature will exceed the predetermined temperature a second time period after the flow of coolant ceases, and
the second time period is greater than the first time period.
6. The system of claim 5 , wherein:
the primary control circuit comprises a primary control circuit temperature sensor configured to sense a temperature of at least a portion of the primary control circuit and supply a primary control circuit temperature signal representative thereof;
the primary control circuit is configured, in response to the primary control circuit temperature signal, to automatically electrically shutdown when the primary control circuit temperature signal indicates that the temperature of at least a portion of the primary control circuit exceeds the predetermined temperature;
the backup control circuit comprises a backup control circuit temperature sensor configured to sense a temperature of at least a portion of the backup control circuit and supply a backup control circuit temperature signal representative thereof; and
the backup control circuit is configured, in response to the backup control circuit temperature signal, to automatically electrically shutdown when the backup control circuit temperature signal indicates that the temperature of at least a portion of the backup control circuit exceeds the predetermined temperature.
7. The system of claim 5 , wherein:
the primary control circuit and backup control circuit are each configured to automatically electrically shutdown when each exceeds the predetermined temperature.
8. An electronic chassis cooling system, comprising:
a chassis having at least a primary control circuit and a backup control circuit mounted therein that are thermally coupled to the chassis, the primary and backup control circuits each operable, when energized, to generate heat;
a plurality of reservoirs formed in the chassis;
a phase change material (PCM), disposed within each of the reservoirs, that changes phase from a first phase to a second phase at a phase-change temperature;
a coolant flow passage formed in the chassis and coupled to receive a flow of coolant; and
a coolant supply system operable to supply the flow of coolant into and through the coolant flow passage at a flow rate that, at least when the electrical devices are nominally energized, is sufficient to (i) remove at least a portion of the generated heat, and (ii) maintain the PCM below the phase-change temperature,
wherein the reservoirs, and the PCM disposed therein, are formed in the chassis such that, if the flow of coolant ceases when the primary and backup control circuits are energized:
primary control circuit temperature will exceed a predetermined temperature within a first time period after the flow of coolant ceases,
backup control circuit temperature will exceed the predetermined temperature a second time period after the flow of coolant ceases, and
the second time period is greater than the first time period.
9. The system of claim 8 , wherein the coolant supply system comprises:
a coolant reservoir having a volume of coolant disposed therein; and
a coolant pump having an inlet and an outlet in fluid communication with the coolant reservoir and operable to supply to the flow of coolant to the coolant flow passage.
10. The system of claim 8 , further comprising:
a plurality of heat sink devices coupled between the electrical devices and the chassis, to thereby thermally couple the electrical devices to the chassis.
11. The system of claim 8 , wherein the chassis comprises a cold plate having the plurality of reservoirs and the coolant flow passage formed therein.
12. The system of claim 11 , wherein the cold plate is disposed to transfer heat from a surrounding environment to the coolant.
13. The system of claim 8 , wherein:
the primary control circuit comprises a primary control circuit temperature sensor configured to sense a temperature of at least a portion of the primary control circuit and supply a primary control circuit temperature signal representative thereof;
the primary control circuit is configured, in response to the primary control circuit temperature signal, to automatically electrically shutdown when the primary control circuit temperature signal indicates that the temperature of at least a portion of the primary control circuit exceeds the predetermined temperature;
the backup control circuit comprises a backup control circuit temperature sensor configured to sense a temperature of at least a portion of the backup control circuit and supply a backup control circuit temperature signal representative thereof; and
the backup control circuit is configured, in response to the backup control circuit temperature signal, to automatically electrically shutdown when the backup control circuit temperature signal indicates that the temperature of at least a portion of the backup control circuit exceeds the predetermined temperature.