Cooling aggregates’ design increases fin count
Two thermally optimised, hollow fin cooling aggregates have been introduced by Fischer Elektronik. The LA 34 cooling aggregate measures 80 x 83mm and the LA 35 measures 160 x 83mm.
They have been introduced in response to challenges posed by increased power densities in electronics and power electronics systems which require the use of efficient cooling methods in order to meet the component life specified by the manufacturer, explains Fischer. The really big thermal power losses, e.g. for converters or switchgears, are often a few kW and are very effective to heat via cooling aggregates. The LA 34 and LA 35 have been added to the company’s portfolio of cooling aggregates and are also available with an additional airflow chamber for generating a laminar air flow (part numbers LAV 34 and LAV 35).
The aggregates are an extruded U-shaped aluminium profile with a special press-in geometry into which extruded aluminium hollow fins are pressed, using special devices and tools. The 14mm thick base plate on one side ensures a good heat spreading within the structure, but also serves as a mounting surface for the electronic devices to be cooled. The high-performance fans have a volume flow of 222m³/h and are adjusted in terms of their performance data specifically to the overall structure and the geometry of the heat exchange surfaces of the aggregates, reports Fischer. Depending on the customer’s application environment, the axial fans are available in 12, 24 and 48V options.
The hollow fins are made with very thin walls and the press-fit geometry in the base profile has also been developed to have a narrow pitch. This increases the number of fins, specifically by two fins, compared to conventional variants of the same dimensions. The total number increases from five to seven for the same installation space per chamber, says the company, to result in a larger surface for heat dissipation so that an improvement in efficiency is also achieved in the field of thermal performance.
The new design and construction also contribute to weight saving, compared to other superstructures in the same geometrical dimensions, or approximately 1.2 kg per metre for LA 34 and 2.1 kg per metre for LA 35. Additional mechanical CNC processing, modifications or special designs and surfaces can be implemented according to customer-specific specifications.