Page 148 - Introduction to Transfer Phenomena in PEM Fuel Cells
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Heat Transfer Phenomena     137
                           4.4.2.4. Integrated heat sink cooling
                             This  method is obviously ingenious; it involves the heat sink
                           phenomenon as it provides efficient heat transfer from the stack by thermal
                           conduction through the sink, then by convection (natural or forced) to the
                           surrounding environment (see Figure 4.5).













                                             Figure 4.5. Integrated heat sink cooling


                           4.4.2.5. Cooling by plates

                             This is the solution that is found most often in the PEMFC stack; these
                           plates are prefabricated and inserted into the stack. There are even perforated
                           bipolar plates designed specifically to carry coolants (air, water, etc.), in
                           addition to hydrogen and oxygen. For this method, a whole control system
                           should be considered; temperature regulation would be essential to avoid the
                           dehydration of the membrane or its blockage with excess water. Figure 4.6
                           shows a typical diagram of a plate cooling system.


















                                                 Figure 4.6. Cooling by plates
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