Shell Heat Exchanger Research Articles

Design of metal foam baffle to enhance the thermal-hydraulic performance of shell and tube heat exchanger

Solid baffles are widely used in shell and tube heat exchanger (STHX), while the highly increased flow resistance and dead zones remain serious drawbacks in the applications. To address this issue, metal foam baffle is proposed in this study to replace solid baffle. The numerical model with considering the thermal non-equilibrium between fluid and foam baffles was established. Laminar flow is assumed in the foam baffles region and the realizable k-ε turbulence model is assumed in the open region. Effects of porosity, pore density, thickness and number of foam baffle (N) on the performance were examined. Results show the foam baffles always lead to lower pressure drop of STHX compared to the solid baffles. Compared to five 2 mm thick solid baffles, five 6 mm thick metal baffles with the porosity of 0.80, 0.85 and 0.90 results higher outlet temperature at the pore density greater than 80, 120 and 160 PPI, respectively. The metal foam baffle leads to higher outlet water temperature compared with solid baffles at the baffle number N ≤ 7. The foam baffles with optimum pore parameters reduced the pressure drop by 12.9 % and increase the outlet and inlet temperature difference by 31.0 % compared to the solid baffles.

Analysis of Soot Deposition Effects on Exhaust Heat Exchanger for Waste Heat Recovery System

This study investigates the thermal–hydraulic behavior and deposition characteristics of a shell and tube exhaust heat exchanger using a CFD-based predictive model of soot deposition. Firstly, considering the influences of thermophoretic, wall shear stress, and other deposition and removal mechanisms, a predictive model is developed for long-term performance of heat exchangers under soot deposition. Then, the variations in exhaust heat exchanger performance during a 4 h deposition period are simulated based on the model. Subsequently, the variation of deposition distribution and different deposition velocities are also evaluated. Finally, an analysis of the long-term performance of the exhaust heat exchanger under varying gas velocities and temperature gradients is conducted, revealing the performance variations under all engine-operating conditions. Results show that the deterioration in normalized relative j/f1/2 varies from 5.26% to 24.91% under different work conditions, and the exhaust heat exchanger with high gas velocity and low temperature gradient exhibits optimal long-term performance.

Effects of baffles and springs in shell and multi-tube heat exchangers: Comparative approach

Shell and multi-tube heat exchangers (SMTHX) are widely used in various industries such as power generation, chemical processing, and refrigeration due to their high efficiency and flexibility. Improving heat transfer within an SMTHX is critical for enhancing overall performance and efficiency. This study investigates the comparative effectiveness of using baffles versus spring wires to enhance heat transfer in SMTHXs. Both experimental and numerical analyses were conducted over a Reynolds number range of 8500–12500, focusing on key parameters such as the Nusselt number, pressure drop, and exergy efficiency. The experiments were performed with a variable cold water flow rate on the shell side and a constant flow rate on the tube side. The numerical model was validated against experimental results. The findings reveal that the Nusselt number increases to 62 with baffles and to 65.5 with spring inserts, representing improvements of 1.54 and 1.61 times, respectively, compared to a plain tube under identical conditions. While the pressure drop for baffles is significantly higher than for spring inserts, the springs show a pressure drop that is 87 % of that observed with baffles. Additionally, exergy efficiency is superior with spring inserts. These results demonstrate that spring inserts are more effective than segmental baffles in enhancing heat transfer in SMTHXs. The study provides valuable insights into the mechanisms of heat and fluid flow, supported by visualizations of velocity, temperature, and pressure contours and streamlines.

Thermo-hydraulic performance of parallel multi-shell and multi-helical coiled tube heat exchanger CFD model with Taguchi-grey relational analysis

This study utilized four distinct shell and helical tube heat exchanger layouts to numerically evaluate the thermal and hydraulic efficiency of each arrangement. The numerical research was conducted using ANSYS FLUENT 2022R1. Currently, there has been no research conducted on the investigation of multiple helical coiled tubes enclosed by multiple shell heat exchangers. This study aimed to optimize various tasks using the Grey Relational Analysis approach in combination with the Taguchi method to maximize thermal efficiency and minimize pressure drop.A parallel configuration was used to connect two to three concentric helical tubes, with each helical tube being enclosed by a shell to control the flow of fluid. The P–P-2M − 36 design, consisting of two helical tubes, has the highest enhancement ratio of Uo = 26.75 %, when compared to the P–P-3M − 36 configuration. Similarly, the P–P-2M − 42 configuration enhances Uo by 38.42 % in comparison to the P–P-3M − 42 configuration. These findings demonstrate that a configuration consisting of two helical tubes exhibits a higher enhancement ratio of Uo compared to a configuration consisting of three helical tubes. The P–P-3M − 36 design, which consists of three helical tubes, exhibits a minimum pressure drop of 39.19 % compared to the P–P-2M − 36 configuration. Similarly, the P–P-3M − 42 configuration reduces pressure drop by 37.76 % compared to the P–P-2M − 42 configuration. The P–P-3M − 36 configuration is designed to simultaneously reduce pressure drop and boost heat transfer rate. The model achieves the optimal values for heat transfer rate and pressure drop at a Reynolds number of 55,000.

Experimental performance analysis of methanol adsorption in granular activated carbon packed bed through design of a double pipe heat exchanger with longitudinal fins

Activated carbon (AC) is essential for its exceptional adsorption properties and high surface area in various applications. Adsorption/desorption (A/D) processes with AC can be exothermic or endothermic, necessitating improved heat exchanger (HE) designs due to AC's low thermal conductivity. This study presents an A/D HE design with longitudinal fins in the sorption bed to enhance heat transfer during methanol A/D in AC. Bed heating/cooling uses water flowing through pipes inside the HE. Experimental investigations focus on thermal characteristics and A/D efficiency under diverse conditions, comparing results to a base non-finned HE design. Various experiments measured HE shell temperatures at different water flow rates while varying the sorption bed condition (vacuumed, filled with air, or methanol). The finned HE design showed a 1.8 °C increase in maximum bed surface temperature and a 3-h, 40-min reduction in process time compared to the non-finned HE. Subsequent tests with the finned HE at different water flow rates (5, 10, and 15 l/min) demonstrated superior heat transfer at 15 l/min due to turbulent flow enhancement. Additionally, adsorption ceased at a bed temperature of 54 °C. These findings highlight the efficacy of finned HE for optimizing methanol A/D processes, offering insights into improving heat transfer in AC-based systems.

Design of a Shell and Tube Heat Exchanger for Methyl Chloride Production

This paper presents the design and analysis of a shell and tube heat exchanger specifically tailored for the efficient handling of methyl chloride. The utilization of heat exchangers in industrial processes is well-established, yet the unique properties and requirements of methyl chloride demand a specialized approach to design. Through a comprehensive literature review and an in-depth exploration of previous designs, this study outlines the key considerations and challenges in creating an effective heat exchanger for this application. The Tubular Exchanger Manufacturers Association (TEMA) standard guides the design process for the heat exchanger, providing the necessary dimensional specifications. Alongside these, specific details regarding the working fluid are meticulously defined. The evaluation of these parameters involves manual calculations using the Microsoft Excel application to assess the performance of the designed heat exchanger. Findings from the study suggest that the designed heat exchanger meets established standards. With 85 tubes and an effective value surpassing 75%, it demonstrates strong performance. A high tool effectiveness value signifies the heat exchanger's commendable operational capability.

Hydrothermal analysis of hybrid nanofluid flow inside a shell and double coil heat exchanger; Numerical examination

In a shell-and-coil heat exchanger, employing a double coil instead of a simple coil causes more heat transfer compared to a simple coil because the double coil improves heat exchange through enhanced fluid flow and turbulence, enabling a longer tube length in constrained locations.. In addition to reducing fouling and the requirement for maintenance, the helical shape may also provide the benefit of a self-cleaning action. Ensuring a more even flow distribution also maximizes the heat exchanger's surface area use and reduces low flow zones. Applications needing compact solutions without compromising performance especially benefit from this design's versatility, allowing customization to meet unique operational demands. In numerous industrial applications, helical coils offer substantial benefits in terms of effectiveness, upkeep, and design freedom.In the present work, heat transfer and fluid flow in a shell-and-coil tube heat exchanger equipped with a double helical coil are evaluated numerically. The employed heat transfer fluids are water-based hybrid nanofluids, including TiO2-Mgi/water and AG-HEG/Water. The obtained outcomes are compared with the results of pure water. The range of considered Reynolds numbers is 500 – 2000. This work consists of two sections. In the first part, the impact of the type of hybrid nanofluid on the hydrothermal behaviour of the proposed heat exchanger is analysed. The volume concentration of the nanoparticles here is ϕ1 = ϕ2 = 0.3. In the second section, the best hybrid nanofluid is selected according to the results of the first section; then, the impact of the nanoparticles' volume concentration on the thermal performance of the proposed heat exchanger is evaluated. Three various nanoparticle volume concentrations, including ϕ1 = ϕ2 = 0.1, ϕ1 = ϕ2 = 0.3, and ϕ1 = ϕ2 = 0.5, are considered, and the results are compared with those of the pure water case (ϕ1 = ϕ2 = 0).The obtained results show that amongst the different heat transfer fluids considered, the Water/MgO-TiO2 model shows the most outstanding value of thermal performance in all the studied Reynolds numbers. Also, the obtained numerical results show that the use of the proposed double coil tube leads to an increase in the heat transfer rate.

Numerical exploration of the impact of fluid type in a uniquely designed shell and spiral tube heat exchanger

Shell and spiral tube heat exchangers are widely favored in refrigeration and applications such as heat recovery systems, food processing, and heat storage. Researchers' primary focus is to discover a simple and cost-effective approach to improve the efficiency of heat exchangers. The research employed a specially designed shell and spiral tube heat exchanger to enhance efficiency. This research involved utilizing ANSYS FLUENT CFD software to analyze the thermodynamic efficiency and predict heat transfer in the specified converter. The analysis incorporated factors such as displacement velocity coefficient and friction coefficient. Researchers are focused on finding a simple and cost-effective approach to improve the efficiency of heat exchangers. Furthermore, the selection of nanohybrid fluids is a crucial factor influencing the thermohydraulic performance of shell and spiral tube heat exchangers. Among the three fluid nanohybrids chosen for simulation, the water nanohybrid exhibited superior temperature performance, surpassing all other liquids. Furthermore, the optimal thermal performance for the hybrid nanofluid was observed at φ1 = φ2 = 0.7.

Analisis Efisiensi Kinerja Heat Exchanger Tipe Shell and Tube Berdasarkan Parameter Laju Alir dan Fouling Factor

The purpose of this study is to determine the results of the evaluation of shell and tube type heat exchanger performance efficiency based on flow rate parameters and fouling factors. In the evaluation of Heat Exchanger (HE-105) performance, two types of data collection were carried out, namely primary data collection used for basic analysis of Heat Exchanger (HE-105) performance evaluation at refinery facilities at PT X and secondary data collection was carried out as a calculation step in the evaluation of Heat Exchanger (HE-105) performance. The results showed that the actual average Rd (fouling factor) value of 0.0012 kcal/m2 hr C is which greater than the design Rd, this is due to the accumulated fouling. The average value of efficiency in the design is 98.41%, and the actual efficiency is 86.29%. The actual average efficiency value is smaller than the design average efficiency value, this is due to the influence of the high flow rate which causes the contact time between temperatures to decrease. However, the average efficiency value is still relatively high, indicating that the Heat Exchanger (HE-105) is still very feasible to use.

Numerical Analysis and Design for Thermal Efficiency Optimization using Al2O3 Nanofluids in Shell and Tube Heat Exchangers

In this study, the efficacy of aluminum oxide (Al2O3) nanofluids at a 2% concentration for enhancing heat transfer in shell and tube heat exchangers is evaluated. By employing SOLIDWORKS for the innovative design and Computational Fluid Dynamics (CFD) for simulation, an improvement in heat transfer efficiency over traditional hot water systems is identified. Emphasizing the unique properties of Al2O3 nanofluids in augmenting heat transfer rates, the role of advanced CAD and simulation tools in engineering practices is highlighted. Results confirm nanofluids' benefits in improving thermal management systems, indicating their potential to decrease energy consumption and operational costs. Furthermore, the exploration of a novel design for heat exchangers, inspired by but distinct from existing market standards, suggests new avenues for the application of nanofluids in various industrial settings, marking a step towards more energy-efficient technologies.

Structural behavior and mechanical fatigue of plate and shell heat exchangers through finite element analysis

Plate and Shell Heat Exchangers (PSHE) are vital in industries due to their adaptability and efficiency. This study applied the finite element method to analyze PSHE plate behavior, which is challenging to assess experimentally. The equivalent von Mises stress field was determined for four-plate setups under different conditions: internal channel pressure, external channel pressure, and pressure in both branches. Peak stresses were found at corrugation tops during contact, varying stress levels based on operating conditions. Stresses decreased when both branches were pressurized but increased with single-branch pressurization. Internal and external pressure-only scenarios had distinct stress patterns. The chevron angle and corrugation contact points influenced plate stiffness and stress distribution. A fatigue analysis assessed plate lifespan under cyclic loads, with fatigue strength reduction factors applied according to Soderberg, Goodman, and Gerber failure criteria. This comprehensive analysis provides critical insights into PSHE plate performance, aiding in their reliable application in the industry. All numerical data obtained in this work were validated based on experimental studies previously published in the literature for stress and fatigue analysis.

Experimental study of solid particles in thermal energy storage systems for shell and tube heat exchanger: Effect of particle size and flow direction

The solid particle thermal energy storage method offers cost-effective, simple, and high-temperature suitable solutions. It effectively resolves chemical compatibility and thermal stress issues in shell-and-tube heat exchangers. This work studies the quartz sands' particle sizes and flow direction's impact on heat exchanger performance. The results show that heat conduction and natural convection heat transfer mechanisms exist on the particle side. Flow direction minimally affects charge/discharge time and stored energy but significantly impacts delivered/recovered energy and exergy and energy and exergy efficiencies. Optimal performance is achieved when HTO enters from the top during charging and from the bottom during discharging, creating a transparent thermal gradient of “Top Temperature High, Bottom Temperature Low”. This distribution minimizes natural convection losses, resulting in a 15–17 % increase in energy efficiency and an 11–13 % increase in exergy efficiency compared to reverse flow. Smaller particles show slightly faster temperature rise due to lower energy storage density. Large and medium particles perform well, achieving energy efficiencies of 81.5 % and 81.0 % and exergy efficiencies of 62.1 % and 61.8 %, respectively. Small particles have an energy efficiency of 79.0 % and an exergy efficiency of 60.4 %, possibly due to higher porosity and increased heat losses.

Effect of ultrasonic on thermo-hydraulic characteristics of shell and tube heat exchangers with twisted tape

Ultrasonic technology was combined with twisted tape insert technology to improve the performance of shell and tube heat exchangers. The effects of sound intensity, sound frequency, and ultrasonic transducer position on thermal transfer, resistance reduction, and overall performance of shell and tube heat exchangers with twisted tape (STHXTT) at different Reynolds numbers were investigated compared to the non-ultrasonic conditions. The experimental results show that applying ultrasonic can significantly enhance thermal transfer, reduce flow resistance, and improve the overall performance. The maximum increase of Nu is 36.53 %, the maximum decrease of f is 12.50 %, and the maximum value of PEC is 1.41. With the increase in Reynolds number, the performance is enhanced but the resistance reduction and overall performance are weak. When the ultrasonic intensity increases, the thermal transfer and resistance reduction performance is enhanced, but a critical ultrasonic intensity exists. When the ultrasonic intensity is large enough, the ability to reduce resistance is enhanced with the decrease of ultrasonic frequency. When the ultrasonic transducer is installed vertically, the thermal transfer performance is the best, however, the resistance reduction effect is the worst. When installed horizontally, the STHXTT has the best resistance reduction performance but the worst thermal transfer effect.

Effect of oil concentration, viscosity, and surface tension on tube temperature and heat transfer coefficients of R1234ze(E)/oil spray evaporation on an enhanced tube bundle

Shell-and-tube evaporators are widely used in desalination, refrigeration, and petrochemical industries. The heat transfer process in spray-type evaporators combines the droplets impingement at the top rows of the bundles and falling film evaporation for the bottom rows, with a transitional region in the center of the bundle. Spray evaporators are a promising alternative to flooded-type shell and tube heat exchangers because they run with significantly lower refrigerant charge amounts.This study presents new data for the spray evaporation of low-GWP refrigerant/oil mixtures on an enhanced tube bundle. The experiments involved R134a (HFC) and R1234ze(E) (HFO) paired with synthetic Polyolester (POE68 and POE220) lubricants. The tests utilized a boiling enhanced tube (re-entrant cavity tube) and were conducted at saturation temperatures of −6.7 °C, 2.2 °C and 10 °C (20°F, 36°F and 50°F), with heat flux varying from 3 to 35 kW/m2 and oil circulation ratio (OCR) ranging from 0.4 % to 2 %. With the addition of oil, the bundle heat transfer coefficient (HTC) of refrigerant/oil mixtures decreased by 20–50 % at an OCR of 1.2 % and a heat flux of 13.5 kW/m2, across the tested saturation temperatures. The average wall superheat across the bundle exhibited at least a 48 % increase for all the refrigerant/oil mixtures tested at an OCR of 1.2 %. The viscosity of the refrigerant/oil mixture showed a limited influence on heat transfer compared to surface tension, mainly because the oil concentrations were quite small. Oil promoted a partial dry-out of the tubes, especially at the bottom of the bundle. Foaming was observed and increased with heat flux and oil concentration. Foam sheets on the tube bundle created an additional barrier for the liquid refrigerant to reach the tube heat transfer surfaces and thus decreased the overall bundle heat transfer coefficient.

Performance optimization for an optimal operating condition for a shell and heat exchanger using a multi-objective genetic algorithm approach.

In this study, shell and heat exchangers are optimized using an integrated optimization framework. In this research, A structured Design of Experiments (DOE) comprising 16 trials was first conducted to systematically determine the essential parameters, including mass flow rates (mh, mc), temperatures (T1, t1, T2, t2), and heat transfer coefficients (€, TR, U). By identifying the first four principal components, PCA was able to determine 87.7% of the variance, thereby reducing the dimensionality of the problem. Performance-related aspects of the system are the focus of this approach. Key outcomes (€, TR, U) were predicted by 99% R-squared using the RSM models. Multiple factors, such as the mass flow rate and inlet temperature, were considered during the design process. The maximizing efficiency, thermal resistance, and utility were achieved by considering these factors. By using genetic algorithms, Pareto front solutions that meet the requirements of decision-makers can be found. The combination of the shell and tube heat exchangers produced better results than expected. Engineering and designers can gain practical insight into the mass flow rate, temperature, and key responses (€, TR, U) if they quantify improvements in these factors. Despite the importance of this study, it has several potential limitations, including specific experimental conditions and the need to validate it in other situations as well. Future research could investigate other factors that influence system performance. A holistic optimization framework can improve the design and engineering of heat exchangers in the future. As a result of the study, a foundation for innovative advancements in the field has been laid with tangible improvements. The study exceeded expectations by optimizing shell and heat exchanger systems using an integrated approach, thereby contributing significantly to the advancement of the field.

Empirical correlation to analyze performance of shell and tube heat exchanger using TiO2 Nanofluid-DI water in solar water heater

Recent studies have examined the thermal stability and reliability of TiO2 nanofluid-based heat exchangers under long-term operation in solar water heating systems. This includes assessing nanoparticle sedimentation, agglomeration, and degradation over time, as well as their impact on heat transfer performance and system reliability. In this study heat transfer and fluid flow characteristics of TiO2-DI-H2O (deionized water) nanofluid used in a shell and tube exchanger with different baffle angles under turbulent regimes were numerically explored. The proposed setup was run with nanoparticle concentration of 0 %–0.2 % and Reynolds numbers (Re) from 5000 to 15,000. Baffle angles of 10°, 20°, and 30° were chosen for turbulence analysis. It was observed that nanoparticle concentration strongly impacted the thermophysical properties. The results indicated that adding modest concentrations of TiO2 to DI-H2O significantly improves heat transfer and the Nu. At the Re of 5000 and 30° baffles, the Nu was 58; however, at the Re of 15,000, the Nu value was 88. The improvement in heat transfer of 62.85 %, 70.64 %, and 75.06 % was recorded for baffle angles of 10°, 20°, and 30° respectively, Furthermore, a notable increase in friction factor of 13.6 % at Re 15,000 was observed. However, the ideal baffle angle for maximum thermal performance is 30°. Finally, with shell temperature, it was established that 30° baffle orientation could provide the best h and Nu values and improve the overall performance of the heat exchanger. The obtained Nu was also compared with the existing correlations of literature in the turbulent regime with the aid of nanoparticles and presented for case applications.

Comparison of heat transfer characteristics of a heat exchanger with straight helical tube and a heat exchanger with coiled flow reverser

Vertical shell and coiled tube heat exchangers are an important aspect of numerous industrial processes and are renowned for their high heat transfer efficiency, versatility, compact design, easy manufacturability and maintenance. As a novel technique, a coiled flow reverser was used to enhance the thermal performance of shell and coiled tube heat exchangers. Therefore, the impact of employing a coiled flow reverser on the heat transfer characteristics and pressure drop in a counter-current shell and tube heat exchanger is investigated using both numerical and experimental approaches. The results are compared to a straight helical coiled tube heat exchanger. The numerical simulations were carried out by employing computational fluid dynamics (CFD) techniques, and the SIMPLE scheme was implemented through the second-order upwind discretization method. The laboratory device used for experimentation features a shell with an inner diameter of 15 cm, and the coil pitch and coil diameter of both coiled tubes are set at 3 cm and 12.1 cm, respectively. Results reveal that the overall heat transfer coefficient of the heat exchanger with a coiled flow reverser is 39.5 % to 49.9 % higher than that of the heat exchanger with a straight helical tube. The effectiveness ratio of the heat exchanger with coiled flow reverser to the straight helical tube heat exchanger ranges from 1.254 to 1.379. Optimal results are observed at a cold flow rate of 6 LPM and a hot flow rate of 1 LPM for both heat exchangers. Additionally, the coiled flow reverser enhances heat transfer performance at the cost of increased pressure drop. Numerical results are in good agreement with experimental findings, establishing the reliability of the study.

Model based fault detection diagnosis and classification in shell and tube heat exchanger using intelligent techniques

A method for Model-Based Approach for Fault Detection and Diagnosis has been put forth in this research. The purpose of this study is to build a heat exchanger model and to locate, categorize faults in the heat exchanger system. One of the known methods for fault control in industrial processes is fault detection and diagnosis (FDD). Both linear and non-linear systems can benefit from the FDD technique; this work describes fault identification and diagnosis for the non-linear system, the heat exchanger. A realistic mathematical model of the heat exchanger with its set of inputs and outputs has therefore been constructed, as the fault detection of the heat exchanger is related to the mathematical model for its operation. Once the mathematical model has been realized using the formulated equation, the process passes on to fault detection. Residual, which defines the failure symptoms of the system, is used to detect faults. In order to prevent failures and defective circumstances from occurring in existing systems, observer design is employed as one of the most powerful and reliable approaches residual generation. Fault diagnosis is carried out using a Fuzzy logic controller (FLC), which is designed based on the residuals obtained, and fault classification is made using the FLC via a fixed threshold. The paper's primary goals are to reduce errors and enhance non-linear systems' overall performance in industrial processes. According to the findings of the simulation, errors in sensors, processes, and actuators can be classified according to a set threshold, and they can be controlled using a traditional PID controller.

Digital Shadow-based Control of Temperature and Fault Classification in Shell and Tube Heat Exchanger using Fuzzy Logic Technique

Digital Shadow-based Control of Temperature and Fault Classification in Shell and Tube Heat Exchanger using Fuzzy Logic Technique

KAJI EKSPERIMEN DAN SIMULASI PENGARUH SUDUT DOUBLE SEGMENTAL BAFFLE DAN LAJU ALIRAN FLUIDA PADA HEAT EXCHANGER JENIS SHELL AND TUBE PADA MESIN MAIN EXTRUDER TERHADAP KEBAIKAN PERPINDAHAN PANAS

Shell and Tube Heat Exchanger (STHX) is very important for its use in the industrial world which can support the continuity and success of the entire network process. Various kinds of research have been carried out to increase the heat transfer coefficient and effectiveness of Shell and Tube Heat Exchangers (STHX) both experimentally and by simulation. This research examines the increase in heat change coefficient and effectiveness of STHX with variations in baffle angles of 0°, 10°, and 20° with fluid mass flow rates of 2, 4, and 6 kg/s. As a result, STHX with a baffle angle of 0° has the largest heat change coefficient value than STHX with a baffle angle of 10° and 20° both during experiment and simulation, values ​​ranging from 4218 W/m²C and 4226 W/m²C at a baffle angle of 0° when the fluid flow rate is increased to 6 kg/s. Keywords: Shell and Tube Heat Exchanger, baffle angle configuration, double segmental baffle, total heat transfer coefficient, effectiveness, CFD (Computational Fluid Dynamics).