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Design Innovations
Figure 2 : The TOffee cloud-based fluid topology optimization platform – processing an optimization job
Figure 3 : Cross-flow ( left ) and counter-flow ( right ) heat exchanger designs
In this way , the performance of the heat exchanger can be predicted using a minimum of assumptions and the maximum of high-fidelity simulations . In addition to performing analyses of the performance of the topology-optimized heat exchanger , we performed CHT analyses of conventional PCHX designs . We judged that it was necessary to perform these expensive simulations instead of using one of the many correlations available in the scientific literature because the strong variability of results in the literature means that the applicability of the correlations is extremely limited . The extra simulation of the conventional design is the best way of providing a like-for-like comparison of results . The conventional design chosen to provide comparisons is a staggered-aerofoil design like that shown in Figure 4 .
The performances of both the conventional and TOdesigned PCHXs were analyzed under two different flow conditions , one a laminar condition and one a turbulent condition ( PCHX geometry parameters and flow conditions provided in Table 1 ). The fluid media were helium / helium while the solid medium was an Inconel alloy . The flow conditions were taken from Guillen et al ., who used them to optimize conventional PCHX designs . Turbulence was modeled using a k-epsilon RANS model . Illustrative diagrams of temperature and velocity streamlines for the counter-flow heat exchanger and conventional aerofoil heat exchanger are shown in Figure 5 . The heat transfer performance of the heat exchanger is quantified using the non-dimensional Nusselt number
Figure 4 : Conventional counter-flow PCHX design www . heat-exchanger-world . com Heat Exchanger World September 2022
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