Test Facilities for a Continuous Transition From Mini- to Microchannels

Two different experimental set-ups are suggested which both have the advantageous features that channels of continuously varying size between mini- and microchannels are realized, that these channels are formed between macroparts without any need for microfabrication and last but not least that the channel walls are freely accessible and can be manipulated with high precision by macro surface manipulation techniques. In the limit of vanishing channel height (h → 0) the flow approaches plane channel flow. For small but finite values of h deviations from this limiting flow case are discussed in detail. For one of the experimental set-ups construction details are shown; for the other one (which is still in the conception phase) heat transfer measurements within the microchannels are discussed.