Measuring Moisture Leakage Out of Water Cooling Hardware

Computer processor speeds have increased in recent years to the extent that water cooling is becoming an attractive and sometimes a necessary way of cooling the processors and their associated electronics. Water can conduct heat much faster than air, allowing processors to run at higher speeds at lower acoustic levels. The ability of water to cool computer electronics can be diminished, or even lost, if there is excessive loss of water by permeation through, or leaks past, the various materials and/or connections between materials. Knowing the rate of loss of coolant from cooling systems can help designers determine the maintenance procedures and schedules for their cooling systems. The paper describes a novel, accurate and convenient method for measuring the moisture leakage rates out of water-carrying hardware. The water-filled hardware under test is placed in a chamber that is purged dry with flowing nitrogen gas and the chamber is then sealed. The rate of rise of relative humidity in the chamber is used to determine the rate of moisture leakage out of the water-filled hardware. The errors arising from the hose terminations and the adsorption of moisture by the metal chamber walls and the plastic fittings can be accounted for and corrected. The test duration is typically less than 10 days. The paper presents examples of water leakage out of hoses and tubes and their terminations and out of quick connects.