Performance Assessment of Single and Multiple Jet Impingement Configurations in a Refrigeration-Based Compact Heat Sink for Electronics Cooling

Abstract

The performance of a novel impinging two-phase jet heat sink operating with single and multiple jets is presented and the influence of the following parameters is quantified: (i) thermal load applied on the heat sink and (ii) geometrical arrangement of the orifices (jets). The heat sink is part of a vapor compression cooling system equipped with an R-134a small-scale oil-free linear motor compressor. The evaporator and the expansion device are integrated into a single cooling unit. The expansion device can be a single orifice or an array of orifices responsible for the generation of two-phase jet(s) impinging on a surface where a concentrated heat load is applied. The analysis is based on the thermodynamic performance and steady-state heat transfer parameters associated with the impinging jet(s) for single and multiple orifice tests. The two-phase jet heat sink was capable of dissipating cooling loads of up to 160 W and 200 W from a 6.36 cm2 surface for single and multiple orifice configurations, respectively. For these cases, the temperature of the impingement surface was kept below 40 °C and the average heat transfer coefficient reached values between 14,000 and 16,000 W/(m2 K).

Experimental characterization and model validation of liquid jet impingement cooling using a high spatial resolution and programmable thermal test chip

“…An example is the study by Maddox [19] where an array of twelve K-type thermocouples embedded in the measurement block with a pitch of 3 mm was used to capture the temperature and heat transfer coefficient peak. Other temperature sensors are resistance temperature detectors (RTDs), which can be deposited on the heater surface as RTD film or integrated separately with the heat source [21,22,23], and thermistors which are very sensitive (up to 100 times more than RTDs and 1000 times more than thermocouples) by measuring the change in resistance with temperature. However, thermistors have self-heating problems and have a slow response for transient thermal measurements.…”