(US4574112-A)      A number of conduits, each extend in an associated cooler assembly between feed and return tubes to form a flow path for cooling fluid. The conduit has a set of cooling tubes disposed in the channels of the cooler assembly, each set of tubes including entrance intermediate and exit cooling tubes. The minimum hydraulic diameter (Df) of each flow path extending from the centre of the feed tube to the centre of the return tube is equal to or greater than three fourths of the average hydraulic diameter of the cooling tubes (Dt) to avoid plugging of the flow path at the minimum hydraulic diameter of the flow path under long term operative conditions.    The cooling tubes extending between the feed and return tubes are connected in serial flow communication to provide a tortuous flow path for cooling fluid through an associated cooler assembly. Thus a flow resistance characteristic is produced that ensures a predetermined supply of cooling fluid to each cooler assembly.    ADVANTAGE -   Can use fluid which contains particles suspended and dissolved in it for extended periods of time. (10pp)i    (DE3445191-C2)      The cooling system is applied to a heat-generating electrochemical power source eg a fuel cell pile comprising the layered cell assemblies (12) surrounded by the fuel inlet (14)/outlet (16) distributors and air inlet (18)/outlet (20) distributors. Between each cell assembly (12) are positioned a number of coolant conduits (32) formed as a continuous alternating feed and return matrix supplied by the main inlet (26) and outlet (28) pipes.    The dimensioning of the conduits (32) and their connections wrt. the main inlet/outlet pipes (26,28) is chosen so that their respective mean hydraulic diameters promote efficient circulation and low pressure-loss to ensure a uniform thermal performance throughout the pile.    USE/ADVANTAGE -   Enables convenient addition of fuel cells and extension of cooling system whilst maintaining good coolant circulation and uniform temp. control. Relatively large bore of all pipework permits free flow of any suspended matter in coolant, blockages are avoided and operational continuity enhanced.