DAU - A Miba Group Company

Liquid Cooled Heat Sinks

In addition to the leading edge bonded fin technology the time has come to offer also dependable thermal management with liquid cooling technology.

To provide the customer with the best heat dissipation DAU has already begun to develop highly advanced liquid cooling systems.

This goal in mind and to give the design engineers the possibility not to be restricted in size and to overcome a large number of current liquid cooled heat sink limitations DAU has designed a variety of liquid cooled heat sinks.

The first of these is the famous DAU EASY SYSTEM which has become the favourite choice with an increasing number of major manufactures of high power electronic drive systems.

Users can choose from 3 standard heat sink widths, which are all available to any desired length up to a maximum of 1500 mm.

A variety of parallel and series flow configurations are available to choose from to give the best flow situation to suit the customers specific request.

The position of the water channels has been designed in such way that 98% of all available power semiconductors can be accommodated.

To further in-crease thermal cooling performance of the DAU EASY SYSTEM, DAU has developed special flow accelerators - so called turbulators - which in- crease the coolant velocity in the channels, with only minimal increase in system back pressure.

DAU recommend the use of turbulators generally and especially with water - glycol mixtures.

For applications requiring an open cooling sy-stem or requiring cooling coils with copper tubing DAU offers the Series KL, KLF and KLD with different tube materials to avoid corrosion.

Usually in most designs the tubes are pressed into the aluminium cold plate with a special manufacturing method, which also seals out moisture and provides a uniformly consant interface for a dependable thermal performance.

Table 1 - Typical heat conductivity of various substances:

 Cooling method
Heat transfer coefficient
Gases  25-50
Liquids
 500-1000
Heat transfer by phase change, boiling or condensation (e.g. heat pipe)
 1000-5000

Latest additions to the DAU range of liquid cooling systemsare the new Series UW and HP liquid cooling systems, two ultimate liquid cooling systems with very low thermal resistance performance.

Series UW has micro channels positioned especially in the hot zone area which achieve the best possible heat dissipation from the power semiconductor.

This micro channel is positioned especially in the hot zone area to develop a vacuum soldering process.

Series HP is especially designed for disc power semiconductors like GTO's, IGBT's and IGCT's.

The chill block is used in compressive clamp systems and is designed to dissipate heat losses of 1.5 KW and up.

Due to its internal construction the pres-sure drop is very small.

Furthermore a majority of cooling products involve some form of customisation. This means different cooling techniques as well as production methods.

Complete design analysis, modelling, prototyping, design assistance and manufacturing is provided by DAU.

For custom product assistance please consult DAU Applications Enqineering Department.