Ali Çelik

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.

Improved indoor air quality (IAQ) through ventilation protects the health of occupants, reduces maintenance and repair costs, and extends the lifespan of buildings. Increases in heating and cooling costs associated with ventilation can be reduced through heat recovery. In heat-recovery ventilation (HRV) systems, the energy costs of decentralized and local systems are lower than those of centralized systems. The objective of this study is to design energy-efficient cubic cross-flow plate heat exchangers (PHEs) with optimal geometry and operating conditions for decentralized and local HRV systems. The research was conducted using Computational Fluid Dynamics (CFD) experiments based on the Taguchi experimental design (L16 OA). The objective is to optimize the three performance metrics—the sensible thermal effectiveness (STE-), the ratio of recovered thermal power to consumed hydraulic power (TPHP), and the combined effect (TPHP) of these two performance metrics—to achieve the ”Larger the Better”. The optimal PHE design is B-20-10-240 for STE, C-20-25-100 for TPHP, and C-20-25-120 for TPHP. For B-20-10-240, the flow rate, recovery thermal power, STE, TPHP, and TPHP are 173 m³/h, 717 W, 79.47%, 67.31, and 53.48, respectively. For C-20-25-100, the flow rate, recovery thermal power, STE, TPHP, and TPHP are 32 m3/h, 67 W, 39.81%, 389.18, and 154.94, respectively. For C-20-25-120, the flow rate, recovery thermal power, STE, TPHP, and TPHP are 48 m3/h, 108 W, 43.80%, 367.84, and 161.11, respectively. The thermal and hydraulic performance of all PHEs was compared and validated using correlations and methods in the literature. In addition, the thermal performance was……