The prediction of flow distribution in flow manifolds is important in the design of heat exchangers. The pressure drop aong the flow in header is the most influential factor on flow distribution in flow manifolds. The various continuous models available in the literature fail to predict satisfactorily the pressure distribution in the headers of the flow manifolds. In this paper, a discrete model matching with the real physical phenomenon is proposed to predict the pressure distribution in headers. Experimental evaluation of relevant flow characteristic parameters has been carried out to support the discrete model calculations. The validity of the theoretical discrete model is tested with experimental results under specific conditions. Refined experimental probes for pressure heads with ultrasonic measuring device were used to obtain accurate results. The experimental results fully substantiate the soundness of the theoretical prediction. In addition, the advantage of the ability to accoummodate local disturbances in the discrete model has been pointed out. The effect of some local disturbance may be substantial. As a result of the analysis presented in this paper, improved designs of flow manifolds in heat exchangers can be realized to assure operation safety under severe operating conditions.
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