After prototype testing verified Coolit predictions to be accurate within 5%, a major German
developer of surgical and medical aesthetic lasers used Coolit to optimize its TEC-cooled designs.
The lasers are built from expensive laser diode modules that have different heat spreader plates
and are cooled by arrays of thermal electric coolers (TECs). Modeling TECs in most CFD packages
is difficult. Several iterations are needed to find the thermal resistances for the hot and cold
sides of the TECs and the operating conditions that determine cooling power and heat dissipation.
The analysis is especially difficult when an array of TECs cools an asymmetrically positioned heat
source, such as a laser bar. Depending on the heat spreading capacity of the laser module's base
plate, the TECs will have different operating conditions and consequently different cooling power.
Munich-based thermal consultant, AMS Technologies AG, performed the analysis by combining arrays
of TECs into Coolit models. The pumping power of the individual TECs, the coefficients of performance,
the temperature distributions and thermal resistance of the heat sink were obtained and available for
optimization. The results also were used to establish selection guidelines for the laser diode modules.
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