This study employs Computational Fluid Dynamics (CFD) simulations to evaluate the thermo‐hydraulic performance of a solar air heater (SAH) equipped with a sinusoidal absorber plate and either arc‐ or sinusoidal baffles. The novelty lies in combining a sinusoidal absorber surface with different baffle geometries and systematically evaluating baffle pitch‐to‐height ratios (
P
/
e
= 8, 10, and 12) over a Reynolds number range of 5000–20,000. Using a grid‐independent and experimentally validated numerical model, results revealed that the baffles substantially enhanced convective heat transfer by promoting flow separation, vortex formation, and boundary‐layer disruption. Among the configurations, the arc‐shaped baffle provided the highest heat‐transfer enhancement. As the Reynolds number increased from 5000 to 20,000, the arc baffle's heat transfer coefficient increased from approximately 18 to 34 W/(m
2
·K), and the average Nusselt number rose from 38 to 72. Furthermore, at low Reynolds numbers, the arc‐shaped baffle improved thermal performance by up to 22% compared with the sinusoidal baffle. Because this heat‐transfer improvement was accompanied by a higher pressure drop, thermo‐hydraulic optimization was essential. The pitch‐ratio analysis demonstrated that
P
/
e
= 10 provided the best compromise between heat transfer enhancement and flow resistance, while
P
/
e
= 8 delivered the highest overall thermal performance. These findings confirm that optimized baffle geometry and spacing significantly improve SAH performance, providing useful guidance for the design of more efficient solar thermal air‐heating systems.
The use of artificial baffles is an effective passive method for enhancing heat transfer in solar air heaters (SAHs). This study numerically investigates the thermo-hydraulic performance of a channel equipped with trapezoidal baffles. Using Computational Fluid Dynamics (CFD), the study analyzes the effect of the relative pitch (P/W) of the baffles and varying inlet velocities (v = 2 to 6 m/s) on the Nusselt number ratio (Nu/Nu0), friction factor ratio (f/f0), and the overall Thermo-Hydraulic Performance Factor (TPF). The results indicate that the introduction of trapezoidal baffles disrupts thermal stratification but increases pressure drop. The model with a relative pitch of P/W = 0.105 (Model P3) demonstrated the optimal balance between heat transfer enhancement and flow resistance, achieving the highest TPF.
Susu Qi· 2026 5th International Confe...· 0 citations
This research presents a detailed computational assessment of a shell-and-tube heat exchanger equipped with helical baffles, emphasizing the
influence of baffle pitch on the system’s overall thermal and hydraulic behavior. The primary aim was to enhance heat transfer capability while
limiting pressure losses, which is an essential requirement for industrial sectors such as energy production, petrochemicals, refrigeration, and
HVAC (Heating, Ventilation, and Air Conditioning) applications. The heat exchanger model was constructed in CATIA V5, and CFD (Computational
Fluid Dynamics) simulations were performed in ANSYS Fluent 15.0 to analyze the impact of different baffle pitches (ranging from
26 to 50 mm) on shell-side performance parameters: pressure drop, temperature difference, and total heat transfer rate over a mass flow range
between 0.1571 and 0.6284 kg/s. The computational results found a 38-mm baffle pitch as the most efficient configuration, yielding a maximum
heat transfer rate of 14.9 kW and a temperature reduction of 8.4 °C, with a moderate pressure penalty. Visualization of the flow field confirmed
the formation of stable swirling and crossflow zones that promote effective mixing without introducing excessive resistance. The study delivers
a systematic CFD-based analysis covering a broad range of operating conditions and offers practical guidelines for perfecting industrial heat
exchanger designs. The novelty of this work lies in its quantitative evaluation strategy, which decides the best configuration through balanced
consideration of both thermal enhancement and fluid dynamic efficiency. In addition to conventional thermal and hydraulic parameters, the
study introduces a thermal–hydraulic performance metric based on the heat transfer rate per unit pressure drop(Q/ΔP). This index provides
an integrated measure of heat transfer effectiveness compared to pumping power. Analysis of this performance index further confirms that the
38 mm pitch delivers the highest thermal–hydraulic efficiency, confirming it as the best configuration across all tested operating conditions.
D. M. Yadav, M. Basha, Dr. B. Omprakash et al.· Journal of Thermal Engineeri...· 0 citations
The aim of this study is to numerically investigate natural convection heat transfer in an H-shaped cavity filled with Al2O3–water nanofluid, with a particular focus on the influence of W-shaped baffle geometry, its position, and relative height on the thermal performance.
A two-dimensional, steady-state numerical model was developed by solving the Navier–Stokes, continuity and energy equations using the finite volume method coupled with the SIMPLE algorithm. The effects of key governing parameters, including the Rayleigh number (104–106), nanoparticle volume fraction (0–2%), baffle position (upper, lower and combined) and relative baffle height (H/16 and H/8), were systematically analyzed.
The results demonstrate that both the Rayleigh number and nanoparticle volume fraction significantly enhance heat transfer. The baffle configuration plays a crucial role, with the upper baffle position yielding the highest Nusselt number, followed by the combined and lower configurations. In addition, a relative baffle height of H/8 provides slightly better thermal performance than H/16, although both configurations effectively improve convective heat transfer.
This study provides new insights into the combined effects of complex cavity geometry and nanofluid properties on natural convection. The introduction of a W-shaped baffle within an H-shaped enclosure offers an original configuration that contributes to the optimization of thermal systems and advanced heat transfer applications.
F. Zemani, Boumediene Beladjine, Amina Sabeur et al.· International Journal of Num...· 0 citations
Dimpled and embossed surfaces are widely used to enhance the performance of plate heat exchangers (PHEs). In this work, the thermal–hydraulic behavior of a PHE with a newly proposed elliptical embossment pattern was examined through numerical simulation. The study focused on two key geometric parameters—embossment depth and pitch—and their influence on heat transfer and flow resistance. Three‑dimensional simulations were carried out in ANSYS Fluent using the realizable k–ε turbulence model with enhanced wall functions, covering Reynolds numbers from approximately 100 to 2000. The results indicate that both the Nusselt number (Nu) and the thermal–hydraulic performance factor (F) rise with increasing embossment depth and pitch, while the friction factor (f) shows a decreasing trend under the same conditions. These findings suggest that careful tuning of the elliptical profile can achieve a favorable balance between heat transfer enhancement and pressure drop, offering practical guidance for the design of next‑generation high‑efficiency PHEs.
Md. Nahid Uddin Antor, Mohammed Istiak Ahamed, Ajgor Hossen et al.· Engineering· 0 citations
The increasing global demand for clean and sustainable energy has accelerated research on high-performance solar thermal systems. Among these, Solar Air Heaters (SAHs) offer a simple and cost-effective solution; however, their thermal efficiency is strongly influenced by absorber plate geometry. This study investigates the thermal performance of a Solar Air Heater employing parabolic absorber plates with four different configurations: regular inward, regular outward, zigzag inward, and zigzag outward. The performance evaluation was carried out through both experimental investigations and Computational Fluid Dynamics (CFD) simulations using ANSYS Workbench R15.0. The analysis considered inlet and outlet air temperatures, solar irradiance, heat transfer rate, Reynolds number, Nusselt number, and thermal efficiency under operating conditions from 11:00 AM to 3:00 PM. Experimental results demonstrate that the parabolic zigzag (outward) configuration provides the best thermal performance throughout the day due to enhanced airflow turbulence, improved heat transfer, and greater solar energy absorption. At peak solar irradiance (1350 W/m² at 2:00 PM), this configuration achieved the highest experimental thermal efficiency of 28.70%, a heat transfer rate of 75 W/m², and a CFD-predicted efficiency of 31.10%. The CFD results closely agreed with the experimental observations, confirming the reliability of the numerical model with only minor deviations. Comparative analysis further revealed that outward configurations consistently outperform inward configurations, while zigzag profiles provide superior heat transfer characteristics compared to regular profiles. Overall, the parabolic zigzag (outward) absorber geometry proved to be the most effective design for enhancing thermal efficiency and solar energy utilization in solar air heaters. The findings provide valuable guidance for the optimization of absorber plate geometries and support the development of efficient, sustainable, and large-scale solar thermal energy systems.
N. Kumbhare, Dr. Pranay A. Bagde· Journal of Intelligent Decis...· 0 citations
This study presents a numerical investigation of natural convection in a two-dimensional inclined square cavity filled with air and subjected to differential heating. The effects of the Rayleigh number and cavity inclination on heat transfer and flow behavior were investigated for 103 ≤ Ra ≤ 109 and inclination angles of 0°, 15°, 30°, and 45°. The dimensionless Navier–Stokes and energy equations were solved using the finite-element method under the Boussinesq approximation with a steady laminar formulation. A structured quadrilateral mesh with boundary-layer refinement was employed near the differentially heated walls. Mesh-refinement tests and comparisons with benchmark data for the classical square cavity were used to assess the numerical accuracy of the model. The results show that the average Nusselt number increases with the Rayleigh number, reflecting the progressive intensification of buoyancy-driven heat transfer. The effect of inclination is non-monotonic and depends on the Rayleigh number. At Ra = 104, the highest average Nusselt number is obtained at 45°, whereas for Ra ≥ 105, the maximum is consistently observed at 15°. At Ra = 109, the average Nusselt number is 54.475, 55.617, 53.224, and 49.408 for inclination angles of 0°, 15°, 30°, and 45°, respectively. The results indicate that moderate cavity inclination can enhance heat transfer by favorably modifying the interaction between buoyancy and the imposed thermal gradient, whereas larger inclinations progressively reduce the heat-transfer rate. The present results provide a systematic characterization of the coupled effects of Rayleigh number and cavity inclination within the scope of the steady two-dimensional formulation considered.
F. I. Molina-Herrera, María L. López-González, L. I. Quemada-Villagómez et al.· Modelling· 0 citations
We use cookies to run the site and, with your consent, for analytics and to show ads.
See our Cookie Policy.
