Optimization of cubic cross‐flow plate heat exchanger based on thermal performance in buildings sustainability for heat‐recovery ventilation using numerical experiments and TAGUCHI method

Abstract Heat‐recovery ventilation systems improve both energy efficiency and indoor air quality of buildings. These systems' plate heat exchangers (PHXs) offer sustainable solutions by recovering thermal energy and reducing heating–cooling and building maintenance costs. This study examined the numerical designs of cubic and cross‐flow air‐to‐air PHXs for energy recovery and indoor ventilation. Four‐parameter, four‐sublevel PHXs were designed using Taguchi experimental design (L 16 ) and Computational Fluid Dynamics (CFD). Within a flow rate range of 50–200 m 3 /h, the geometric dimensions and operating conditions of the optimally designed PHXs were determined based on two performance indicators: recovered thermal power and sensible thermal effectiveness. The B‐32‐10‐240 PHX model was optimally designed in terms of recovered thermal power. This model recovers approximately 1120 W of heat, has a sensible thermal effectiveness of 77.47%, and has a volumetric flow rate of 276 m 3 /h. The B‐20‐10‐240 PHX model was optimized for sensible thermal effectiveness. It has a sensible thermal effectiveness of 79.47%, recovers approximately 718 W of heat, and has a volumetric flow rate of 173 m 3 /h. The pressure losses of the B‐32‐10‐240 are 2.1 times higher than those of the B‐20‐10‐240. Furthermore, the CFD effectiveness of the optimal PHX models and other models in the L 16 array were compared with and validated against those obtained using the ε‐NTU method. Additionally, the effectiveness of all PHX models were compared to those reported in similar studies.