The thermal–hydraulic model of the PHE relies on cor- relations for the evaluation of the convective heat transfer coefficient and of the friction factor for the flow inside the channels for any given plate surface type and geometry; hence, experimental studies are required for the estimation of the correlation parameters. PHEs that operate for heat recovery with fixed symmetric configurations are commonly used for this task because the evaluation of the convective coefficient is simplified under these conditions. For exam- ple,JacksonandTroupe(1964),Buonopane andTroupe (1969) and Bansal et al. (2001) studied a configuration of three channels and countercurrent single-pass arrangement because it is possible to assume pure countercurrent flow conditions.
Muleyetal.(1999) and Wright and Heggs(2002) rely on the same assumption for the case of PHEs with a large number of channels per pass,since the effects of the
parallel flow channels and of the channels at the PHE extremities (alsoknownas“endeffects”) can be neglected.
In the present paper,the influence of the configuration on the parameter estimation for the PHE thermal modelis studied.The objective is to investigate how the experimental procedure for parameter estimation can further affect the results of the problem of sizing a PHE. Firstly, the thermal model of the PHE is presented leading to two approaches re- garding the pure counter current flow assumption.Further,a parameter estimation procedure that does not have configu- ration restrictions is described. The procedure is experimen- tally tested and the results obtained for both approaches are analyzed and compared.Finally,a sizing problem is solved using the obtained correlations.
The thermal–hydraulic model of the PHE relies on cor- relations for the evaluation of the convective heat transfer coefficient and of the friction factor for the flow inside the channels for any given plate surface type and geometry; hence, experimental studies are required for the estimation of the correlation parameters. PHEs that operate for heat recovery with fixed symmetric configurations are commonly used for this task because the evaluation of the convective coefficient is simplified under these conditions. For exam- ple,JacksonandTroupe(1964),Buonopane andTroupe (1969) and Bansal et al. (2001) studied a configuration of three channels and countercurrent single-pass arrangement because it is possible to assume pure countercurrent flow conditions.Muleyetal.(1999) and Wright and Heggs(2002) rely on the same assumption for the case of PHEs with a large number of channels per pass,since the effects of theparallel flow channels and of the channels at the PHE extremities (alsoknownas“endeffects”) can be neglected.In the present paper,the influence of the configuration on the parameter estimation for the PHE thermal modelis studied.The objective is to investigate how the experimental procedure for parameter estimation can further affect the results of the problem of sizing a PHE. Firstly, the thermal model of the PHE is presented leading to two approaches re- garding the pure counter current flow assumption.Further,a parameter estimation procedure that does not have configu- ration restrictions is described. The procedure is experimen- tally tested and the results obtained for both approaches are analyzed and compared.Finally,a sizing problem is solved using the obtained correlations.
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