Patent ID: 9678025
Date: 2017-06-13
CPC Classifications: G01K,G01N

Claim:
1. A test apparatus for evaporation or boiloff flow measuring to determine thermal performance of a test specimen, comprising: a sealable chamber comprising a vacuum chamber can and a vacuum chamber lid that is selectably sealed to an upper opening of the vacuum chamber can; a cold mass assembly attached to a bottom side of the vacuum chamber lid and locatable within the sealable chamber and comprising: a first liquid passage in communication with the guard vessel to supply the first liquid fluid and to vent evaporation or boiloff from the first liquid fluid; a second liquid in communication with the test vessel to supply the second liquid fluid and to vent evaporation or boiloff from the second liquid fluid; and a warm boundary temperature surface in thermal communication with a lower surface of the test specimen, wherein the upper surface of the test specimen during testing is colder than the lower surface and thus deemed a cold side and a warm side respectively, wherein the first liquid in the guard vessel is maintained at a level higher than the top of the test vessel encompassing the lateral wall assembly and the vessel top of the test vessel creating a steady-state thermal isolation enabling direct measurement of flow of heat.