Method and controller for testing a two-phase cooling device, computer program, and computer-readable medium
A method for testing a two-phase cooling device is provided. The cooling device has a housing surrounding a cavity and a cooling medium within the cavity. The method includes controlling a temperature of ambient air of the cooling device such that the cooling medium within the cavity transitions from its liquid state to its solid state and/or from its solid state to its liquid state, while monitoring a first temperature of the cooling device, determining whether the monitored first temperature fulfills a predetermined criterion, and determining that the cooling device is overfilled with the cooling medium if the predetermined criterion is fulfilled.
1 . A method for testing a two-phase cooling device, the two-phase cooling device having a housing surrounding a cavity and a cooling medium within the cavity, the method comprising:
controlling a temperature of ambient air of the two-phase cooling device such that the cooling medium within the cavity undergoes phase transitions from its liquid state to its solid state and/or from its solid state to its liquid state, while monitoring a first temperature of the two-phase cooling device;
determining whether the monitored first temperature fulfills a predetermined criterion; and
determining that the two-phase cooling device is overfilled with the cooling medium if the predetermined criterion is fulfilled.
2 . The method in accordance with claim 1 , wherein determining whether the monitored first temperature fulfills the predetermined criterion further comprises:
determining at least one graph, which represents the monitored first temperature over a time during which the first temperature is monitored; and
determining whether the at least one graph fulfills the predetermined criterion.
3 . The method in accordance with claim 2 , wherein;
the at least one graph of the monitored first temperature comprises a first section with a falling temperature indicating a supercooling of the cooling medium in its liquid state inside the two-phase cooling device, after that the at least one graph comprises a jump to a freezing temperature of the cooling medium indicating a start of freezing of the cooling medium, after that the at least one graph comprises a second section at the freezing temperature of the cooling medium indicating the freezing of the cooling medium, and after that the at least one graph comprises a third section with the falling temperature, wherein the predetermined criterion is searched in the third section.
4 . The method in accordance with claim 3 , wherein determining whether the at least one graph fulfills the predetermined criterion further comprises:
determining a first derivative of the at least one graph; and
determining an amount of extreme values of the first derivate of the at least one graph during one of the phase transitions and/or within the third section,
wherein the predetermined criterion is fulfilled, if the first derivate of a signal has at least two extreme values.
5 . The method in accordance with claim 3 , wherein determining whether the at least one graph fulfills the predetermined criterion further comprises:
determining a width of the at least one graph during at least one of the phase transitions of the cooling medium and/or within the third section, wherein the predetermined criterion is fulfilled, if the determined width is larger than a predetermined width threshold.
6 . The method in accordance with claim 3 , wherein the first temperature is sensed at a bottom region of the housing, the method further comprising:
monitoring a second temperature of the two-phase cooling device, wherein the second temperature is sensed in a top region of the housing, while monitoring the first temperature; and
determining a difference between the monitored first temperature and the monitored second temperature during at least one of the phase transitions of the cooling medium and/or within the third section,
wherein the predetermined criterion is fulfilled, if the determined difference is larger than a predetermined difference threshold.
7 . The method in accordance with claim 1 , wherein the first temperature is monitored for a predetermined amount of time.
8 . The method in accordance with claim 1 , further comprising:
arranging the two-phase cooling device in a temperature chamber, wherein the temperature chamber encloses the ambient air and enables the control of the temperature of the ambient air, prior to controlling the temperature of the ambient air.
9 . The method in accordance with claim 1 , further comprising:
arranging a first sensor at the housing such that the first sensor has a thermal contact to the housing and is thermally isolated against the ambient air, prior to controlling the temperature of the ambient air.
10 . The method in accordance with claim 9 , wherein the first sensor is arranged at a bottom region of the housing.
11 . A controller for testing a two-phase cooling device, the two-phase cooling device having a housing surrounding a cavity and a cooling medium within the cavity, the controller comprising a processor and a memory, wherein the processor is configured to:
control a temperature of ambient air of the two-phase cooling device such that the cooling medium within the cavity undergoes phase transitions from its liquid state to its solid state and/or from its solid state to its liquid state, while monitoring a first temperature of the two-phase cooling device;
determine whether the monitored first temperature fulfills a predetermined criterion; and
determine that the two-phase cooling device is overfilled with the cooling medium if the predetermined criterion is fulfilled.
12 . The controller in accordance with claim 11 , wherein the controller, to determine whether the monitored first temperature fulfills the predetermined criterion, is further configured to:
determine at least one graph, which represents the monitored first temperature over a time during which the first temperature is monitored; and
determine whether the at least one graph fulfills the predetermined criterion.
13 . The controller in accordance with claim 12 , wherein:
the at least one graph of the monitored first temperature comprises a first section with a falling temperature indicating a supercooling of the cooling medium in its liquid state inside the two-phase cooling device, after that the at least one graph comprises a jump to a freezing temperature of the cooling medium indicating a start of freezing of the cooling medium, after that the at least one graph comprises a second section at the freezing temperature of the cooling medium indicating the freezing of the cooling medium, and after that the at least one graph comprises a third section with the falling temperature, wherein the predetermined criterion is searched in the third section.
14 . The controller in accordance with claim 13 , wherein the controller, to determine whether the at least one graph fulfills the predetermined criterion, is further configured to:
determine a first derivative of the at least one graph; and
determine an amount of extreme values of the first derivate of the at least one graph during one of the phase transitions and/or within the third section,
wherein the predetermined criterion is fulfilled, if the first derivate of a signal has at least two extreme values.
15 . The controller in accordance with claim 13 , wherein the controller, to determine whether the at least one graph fulfills the predetermined criterion, is further configured to:
determine a width of the at least one graph during at least one of the phase transitions of the cooling medium and/or within the third section, wherein the predetermined criterion is fulfilled, if the determined width is larger than a predetermined width threshold.
16 . A non-transitory computer-readable medium embodying programmed instructions which, when executed by a controller for testing a two-phase cooling device, the two-phase cooling device having a housing surrounding a cavity and a cooling medium within the cavity, direct the controller to:
control a temperature of ambient air of the two-phase cooling device such that the cooling medium within the cavity undergoes phase transitions from its liquid state to its solid state and/or from its solid state to its liquid state, while monitoring a first temperature of the two-phase cooling device;
determine whether the monitored first temperature fulfills a predetermined criterion; and
determine that the two-phase cooling device is overfilled with the cooling medium if the predetermined criterion is fulfilled.
17 . The non-transitory computer-readable medium in accordance with claim 16 , wherein the programmed instructions that direct the controller to determine whether the monitored first temperature fulfills the predetermined criterion, further direct the controller to:
determine at least one graph, which represents the monitored first temperature over a time during which the first temperature is monitored; and
determine whether the at least one graph fulfills the predetermined criterion.
18 . The non-transitory computer-readable medium in accordance with claim 17 , wherein:
the at least one graph of the monitored first temperature comprises a first section with a falling temperature indicating a supercooling of the cooling medium in its liquid state inside the two-phase cooling device, after that the at least one graph comprises a jump to a freezing temperature of the cooling medium indicating a start of freezing of the cooling medium, after that the at least one graph comprises a second section at the freezing temperature of the cooling medium indicating the freezing of the cooling medium, and after that the at least one graph comprises a third section with the falling temperature, wherein the predetermined criterion is searched in the third section.
19 . The non-transitory computer-readable medium in accordance with claim 18 , wherein the programmed instructions that direct the controller to determine whether the at least one graph fulfills the predetermined criterion, further direct the controller to:
determine a first derivative of the at least one graph; and
determine an amount of extreme values of the first derivate of the at least one graph during one of the phase transitions and/or within the third section,
wherein the predetermined criterion is fulfilled, if the first derivate of a signal has at least two extreme values.
20 . The non-transitory computer-readable medium in accordance with claim 18 , wherein the programmed instructions that direct the controller to determine whether the at least one graph fulfills the predetermined criterion, further direct the controller to:
determine a width of the at least one graph during at least one of the phase transitions of the cooling medium and/or within the third section, wherein the predetermined criterion is fulfilled, if the determined width is larger than a predetermined width threshold.