Convegni ATI - Accesso riservato soci CTI

Autore: G. Fabbri, M. Lorenzini, S. Salvigni

Collana: CA - 60 - Roma 2005

Note:
A modular heat sink with wavy channels for power electronic applications was characterised in terms of thermal resistance. The assembly is constituted by several plates which are joined together mechanically and form thus channels with wavy walls, through which a forced convective flow of ambient air streams. The power-dissipating component is simulated through an electric heater which distributes a uniform heat flux over the whole of a side surface. First, an assessment of the flow characteristics for the channels is made using a hot wire anemometer to record the velocity profile at
the exit of the channel Then, tests are run for a total dissipated power which varies between 100 and 600 W under steady state conditions. The influence of the spacers interposed between fan and heat sink so as to readjust the flow is also investigated. It is concluded that the thermal resistance is relatively constant over the investigated range and that the five spacers – when they can be employed – perform better.