Heat flow meter instruments

An apparatus for measuring thermal properties of a specimen comprising:

• a first thermoelectric device and a second thermoelectric device, each said device being thermally coupled to a hot plate and a cold plate;
• a heat flow transducer, thermally connectable to a specimen, the combination of said heat flow transducer and said specimen being positionable in thermal contact between said hot plate of said first thermoelectric device and said cold plate of said second thermoelectric device, said heat flow transducer being constructed and arranged to measure heat flowing through said specimen from said .hot plate to said cold plate;
• at least one electric power supply connected to provide controlled amounts of electric power to said first thermoelectric device and said second thermoelectric device to maintain said plates at selected temperatures;
• a closed loop heat exchange system, thermally connecting said cold plate of said first thermoelectric device and said hot plate of said second thermoelectric device, constructed and arranged to transfer heat between said plates;
• and
• a processor connected to receive from said heat flow transducer a signal corresponding to said measured heat, said processor being further programmed to calculate a thermal property of said specimen based on said temperatures and said measured heat.

An apparatus for measuring a thermal property of a specimen comprising:

• a first heat generating device thermally coupled to a hot plate and a second heat generating device thermally coupled to a cold plate;
• a first temperature sensor and a second temperature sensor located in thermal contact with said hot plate and said cold plate, respectively;
• a heat flow transducer, thermally connectable to a specimen, constructed and arranged to measure heat flowing through said specimen before reaching steady-state thermal conditions, the combination of said heat flow transducer and said specimen being positionable in thermal contact between said hot plate and said cold plate;
• at least one electric power supply connected to provide controlled amounts of electric power to said first device and said second device to maintain said plates at selected temperatures;
• and
• a processor connected to receive from said heat flow transducer a signal corresponding to said measured heat, said processor being further programmed to calculate a predicted steady-state value of a thermal property of said specimen under transient thermal conditions based on said measured heat and said temperatures.

A method of measuring a thermal property of a specimen comprising:

• providing a first thermoelectric device and a second thermoelectric device, each said device being thermally coupled to a hot plate and a cold plate, said thermoelectric devices being connected to an electric power supply;
• positioning a specimen, thermally coupled to a heat flow transducer, in thermal contact between said hot plate of said first thermoelectric device and said cold plate of second thermoelectric device;
• establishing selected temperatures of said hot plates and said cold plates by providing simultaneously electric power from said power supply to said first thermoelectric device and said second thermoelectric device;
• measuring heat flowing through said specimen from said hot plate of said first thermoelectric device to said cold plate of said second thermoelectric device by utilizing said heat flow transducer;
• and
• calculating a thermal property of said specimen based on said measured heat and said temperatures.

A method of measuring a thermal property of a specimen comprising:

• providing a first heat generating device thermally coupled to a hot plate and a second heat generating device thermally coupled to a cold plate;
• a first temperature sensor and a second temperature sensor located in thermal contact with said hot plate and said cold plate, respectively, said devices being connected to at least one electric power supply;
• positioning a specimen, thermally coupled to a heat flow transducer, in thermal contact between said hot plate and said cold plate;
• establishing selected temperatures of said hot and cold plates by providing electric power to said first device and said second device;
• measuring heat flowing through said specimen by utilizing said heat flow transducer before reaching steady-state thermal conditions;
• and
• calculating a predicted steady-state value of a thermal property of said specimen under transient thermal conditions based on said measured heat and said temperatures.