Plate-fin Heat Exchanger Research Articles

Multiphysics Studies of 3D Plate Fin Heat Exchanger Filled with Ortho-Para-Hydrogen Conversion Catalyst for Hydrogen Liquefaction

Multiphysics Studies of 3D Plate Fin Heat Exchanger Filled with Ortho-Para-Hydrogen Conversion Catalyst for Hydrogen Liquefaction

Inclined Installation Effect on the Offset Strip Finned Heat Exchanger Designed for a Hybrid Electric Propulsion System in Electric Vertical Take-Off and Landing

The plate-fin heat exchanger was designed for the liquid cooling thermal management system of the hybrid electric propulsion system for an electric vertical take-off and landing (eVTOL) vehicle. The offset-strip fin design was applied, and the performance of the heat exchanger was evaluated, particularly with respect to the inclination of the airflow entering the heat exchanger. The estimated performance during the design phase matched well with the experimental results. The inclination of the heat exchanger had a minimal effect on thermal performance, with a slight increase in performance as the inclination increased. However, the pressure difference along the airflow was affected, likely increasing as the inclination increased. The sensitivity of various parameters on coolant temperature was also investigated. The air inlet temperature had a significant effect on coolant temperature, followed by the coolant flow rate. Therefore, when designing the thermal management system, careful consideration should be given to the ambient air temperature and coolant flow rate.

Performance analysis of a low-pressure cryogenic vaporizer for liquified hydrogen supply system

In this paper, we theoretically investigated the thermal performance of a low-pressure cryogenic vaporizer for liquified hydrogen supply system. A performance analysis model was developed by the modified effectiveness-NTU method considering the axial conduction and phase change of liquified hydrogen. In the analysis model, a plate-fin heat exchanger (PFHE) was chosen as the type of a cryogenic vaporizer. The inlet temperature and pressure conditions of liquified hydrogen were 20 K and 10 bar, respectively and the outlet temperature condition of hydrogen was a room temperature. Based on the theoretical results, we presented effects of geometric parameters on the performance of the vaporizer under the fixed pumping power condition. Especially, it is shown that the effectiveness of the hot fluid and cold fluid exhibit opposite trends depending on the axial conduction. In addition, we presented the effect of the aspect ratio of microchannels on the effectiveness considering both cases where the microchannel heights of the EGW mixture and hydrogen were either the same or different. Also, we showed the effect of the vaporizer length on the performance of the vaporizer. Finally, geometric parameters that can satisfy the two target performances are suggested.

Effect of plate-fin heat exchanger structural parameters on the performance of a cascade refrigeration system

This study investigates the effect of various structural parameters in plate-fin heat exchanger on the performance of a cascade refrigeration system (CRS). Focusing on five key factors—fin thickness, fin type, fin height, porosity, and element axial length—we analyze their contributions to COP, exergy destruction, and entropy production within the CRS. The results reveal that the fin type barely influences the CRS’ performance, the element axial length has the greatest impact, followed by fin height, porosity, and fin thickness, respectively. The COP of the CRS drops by 26.25 % as the element axial length increases from 124 mm to 136 mm, 23.67 % (23.08 %) as the fin height of perforated (straight) fin increases from 6.1 mm to 6.7 mm, and 10.27 % (10.38 %) as the fin thickness of perforated (straight) fin increases from 0.1 mm to 1.3 mm, and the exergy destruction increases by 42.42 %, 37 % (37 %), and 13 % (10.38 %), respectively. The effect of porosity on the CRS’ performance is opposite to that of other parameters. When the element axial length is 124 mm, the fin height is 6.1 mm, and the fin thickness is 0.1 mm, the COP of the CRS reaches the maximum value (0.689). The conclusion can provide data support for the performance optimization of CRS from the structure of the cascade heat exchanger.

A novel balanced teaching-learning-based optimization algorithm for optimal design of high efficiency plate-fin heat exchanger

Plate-fin heat exchangers (PFHE) are crucial for engineering applications. Pursuing high performance in PFHE design through optimal methods is common, yet challenging for traditional optimization approaches. Meta-heuristic algorithms (MAs) continuously achieve significant breakthroughs in this problem. This paper proposes a novel balanced teaching-learning-based optimization (NBTLBO) algorithm for PFHE optimal design, which optimizes entropy generation units and heat transfer area using objective functions derived from thermal modeling. NBTLBO introduces two phases, as straightforward as that of TLBO, that collaborate to balance exploitation and exploration, offering substantial superiority over TLBO. This addresses the limitations of existing TLBO studies that involve complex multiple phases and neglect phase interactions. The experiments reveal that NBTLBO achieves the best ranking in CEC 2014 and 2020 benchmarks compared with many popular MAs and even their enhanced variants. It also yields the best results across all four PFHE design examples, showing significant improvement over TLBO and other existing methods. A non-dominated sorting NBTLBO algorithm is developed for multi-objective PFHE design, achieving improved Pareto results compared to existing methods. It verifies that NBTLBO, despite its simplicity akin to TLBO, effectively balances exploitation and exploration, thereby achieving notably enhanced performance, rendering it a preferred option for tackling global optimization challenges.

Experimental investigation of forced convection heat transfer of heat exchangers with different pin geometries in in-line and staggered design

In this study, the effects of forced convection heat transfer on the surfaces of pin plate heat exchangers with different geometries modified to the heat exchanger form were experimentally investigated. A total of 8 pin fin plate heat exchangers, four of which are staggered and the other four are in-line, were used in the experiments. The heat transfer surface areas of the pin plate heat exchangers are produced equally. The only difference is their geometry, which is produced in four different shapes: triangle, circle, ellipse and square. The experiments were carried out at air velocities of 1 to 6 m/s with 1 m/s increments and at 10 W and 50 W input powers with 10 W increments. The staggered configuration of the pin fin plates demonstrated high performance in heat transfer. The study found that heat exchangers with cornerless pin plates have lower heat transfer compared to those with cornered pin plates. The pressure drops increased as the velocity of the coolant air increased, and the highest-pressure drop was observed in staggered triangular and elliptical pin plate heat exchangers. This research is considered innovative as it involves an experimental comparison between staggered and in-line pin plate heat exchangers in four different geometries, all with equal surface area.

Experimental insights into thermoelectric freezer systems: Feasibility and efficiency

This study presents an experimental investigation into the operational performance of a thermoelectric (TE) freezer system. A freezer unit is composed of two-stage thermoelectric modules, an aluminum plate fin heat exchanger sink with fans positioned either on top or directing airflow through the center, and a cooling block incorporating circulating icy water for heat dissipation. Three distinct configurations, featuring varying numbers of freezer units and fan arrangements, underwent testing using a 300-liter freezer prototype under typical room conditions, specifically at 21 °C. The findings illustrate that the minimum temperature inside the freezer cabinet can achieve −16.0 °C across all configurations. Moreover, the cooling capacity can reach up to 74.7 W, with the thermoelectric coefficient of performance (COP) achieving a maximum of 0.45, while the system COP ranges from 0.23 to 0.28. The minimum TE power consumption and TE system power consumption are recorded at 138.8 W and 174.4 W, respectively, suggesting feasibility for practical residential freezer applications. This investigation sets the stage for the development of TE freezers integrated with ice thermal storage applications.

Enhancing plate-fin heat exchanger hydraulic thermal performance through air-side fin optimization based on pseudo-3D topology optimization

With the expansion of the New Energy Vehicles (NEVs) market, the demand for efficient thermal management systems is increasingly pressing. Topology optimization (TO) methodology is an important way to improve the performance of heat exchangers (HE) in many use scenarios. This study focuses on enhancing the design of air-side fins within plate-fin HE, which are vital components in NEVs thermal management systems. By employing the TO methodology, our research aims to enhance the hydraulic thermal performance of these HE. A pseudo-three-dimensional (3D) flow heat transfer model is used to improve the hydraulic thermal performance of HE by variable density method. An optimization function considering thermal resistance and dissipated power is proposed in this study. The investigation rigorously assesses the effects of different controlling parameters on the results of TO. Following the optimization, a 3D model of the optimized fin configuration is elaborated to analyze the localized fluid dynamics and thermal characteristics. Furthermore, the study evaluates the hydraulic thermal performance of the TO fins under diverse inlet velocities, revealing significant alterations in vortex patterns with velocity increments, which substantially impact heat transfer in the cooling channel. Under varying inlet velocities, the TO fin design exhibits the optimal hydraulic thermal characteristics, demonstrating an enhancement of 9.53% to 22.82% in the comprehensive performance factor (JF) compared to the conventional serrated fin. This research contributes innovative strategies for radiator optimization in thermal management systems of NEVs, fostering advancements in heat exchange efficiency and radiator lightweight.

Heat Transfer during Downflow Condensation of R21 in Plate-Fin Heat Exchanger with Inclined Texture

Heat Transfer during Downflow Condensation of R21 in Plate-Fin Heat Exchanger with Inclined Texture

Thermodynamic and Economic Optimization of Plate-Fin Heat Exchangers Using the Grasshopper Optimization Algorithm

Thermodynamic and Economic Optimization of Plate-Fin Heat Exchangers Using the Grasshopper Optimization Algorithm

Wet cooling of air on plate finned tube heat exchangers

The objective of this paper is to provide the reliable calculation procedure for determining heat and mass flow rates for plate finned tube heat exchangers in dehumidification regimes that can be used easily in engineering practice. For this purpose, the experiments are conducted on two heat exchangers, and datasets for six more heat exchangers are used from literature. Comprehensive database is established with total of 637 sets of data, and it gathers 365 new measurement sets and 272 sets from open literature. The new calculation procedure predicts heat transfer rate and condensate flow rate where new methodology approach (based on the porous velocity, the ratio of characteristic surfaces and hydraulic diameter) is used. Predicted results show 5–10 % deviation for heat duty and up to 20 % for mass flow rate from experimental results, which is of importance to industrial practice.

Experimental study on thermal-hydraulic characteristics of cryogenic plate-fin heat exchangers

Plate-fin heat exchangers (PFHEs) are used in diverse applications because of their superior capabilities. Recently, the demand for PFHEs has increased in cryogenic industries. Therefore, evaluating the thermal and hydraulic performances of PFHEs under cryogenic conditions is crucial for effectively designing them. In this study, the thermal–hydraulic characteristics of cryogenic nitrogen gas flowing through PFHEs were investigated experimentally. Two PFHEs with different fin geometries are used in this study. The hydraulic diameters of the PFHEs were 2.13 and 1.47 mm. The experimental ranges of the Reynolds and Prandtl numbers were 345–7800 and 0.72–0.75, respectively. From the experimental results, a heat transfer correlation based on the Diani correlation was derived in both turbulent and laminar regimes, with root mean square percentage errors of 0.68 and 6.9 % for the turbulent and laminar regimes, respectively. For hydraulic performance, the calculated pressure drop demonstrated good agreement with the experimental data, with a root mean square percentage error of 13 %.

Optimization investigation for heat transfer enhancement of fins for plate-fin heat exchangers in cryogenic helium systems

In order to further improve heat transfer performance and high compactness of plate-fin heat exchangers (PFHEs) in cryogenic helium systems, a new type of perforated-serrated fins is proposed by combining traditional serrated and perforated fins. In this paper, the flow and heat transfer characteristics of helium in perforated-serrated fins and serrated fins channels at low-temperature are investigated using numerical simulations. The numerical model invokes the properties of low-temperature helium by NIST-Real-Gas-Model. Meanwhile, Colburn factor j, friction factor f and JF factor are qualitatively evaluated for pressure drop, heat transfer performance and thermo-hydraulic performance, respectively. The results show that new perforated-serrated fins have better heat transfer performance. The j factor of the new fins increases by 32.58% to 15.63% compared with serrated fins. The flow performance of perforated-serrated fins is slightly worse than that of serrated fins, but the overall thermo-hydraulic performance is better, especially at low Reynolds number. Compared with serrated fins, the JF factor of perforated-serrated fins is significantly higher and increase by 25.95% to 10.86%. The optimizing method of fins structure can be used in the actual design of PFHEs in cryogenic helium systems.

Parametric design optimization and thermodynamic analysis of plate fin heat exchanger for helium liquefaction system

The plate-fin heat exchanger is one of the most important components of helium liquefaction system as it recovers cold energy from helium gas in the cold box. Because of larger heat transfer surface area and compact geometrical configuration, plate-fin heat exchangers are widely used. The design of heat exchanger using helium as a cryogenic fluid needs high thermodynamic performance with minimum pressure drop which particularly requires the optimization of dimensional array and its geometrical configurations. In this regard, a parametric investigation was performed to compute the effective geometrical parameters and its effect on thermodynamic (effectiveness and log-mean temperature difference) performance has been discussed in detail. The present study aims to design optimization and thermodynamic performance evaluation of plate-fin type heat exchangers used in helium liquefaction systems. The developed helium liquefaction model has been simulated for the most critical liquefier with and without liquid nitrogen precooling, mixed mode, and refrigeration mode. Each component of the liquefaction model has been technically and thermodynamically analyzed and, in particular, four plate-fin heat exchangers have been considered and designed accurately using Aspen EDR®. Initially, the sensitivity analysis was carried out to characterize the most significant geometrical parameters (fin thickness, height, number and arrangement of layers, frequency, and fin type) and their effect on thermodynamic performance and pressure drop. After that, the artificial intelligence model was used to determine the optimal range of such geometrical variables in which the heat exchanger has maximum effectiveness and log mean temperature difference. Finally, the operating conditions obtained from cycle modeling and optimized geometrical datasets have been applied in commercial simulation software Aspen EDR® for plate-fin heat exchangers design. Finally, a comparative thermodynamic analysis has been carried out to determine the performance of all the designed heat exchangers operating at four different modes (boundary conditions).

Plate-fin heat exchanger optimal design for industry employing both single and multi-objective chaotic opposition based Kho-Kho algorithm

Manufacturers of heat exchangers are constantly looking for new and better designs because it is essential to the preparation of any engineering gadget, like a Plate-fin heat exchanger (PFHE). To find an optimal design of a plate-fin heat exchanger, both hydraulic and economic issues are considered by proposing an optimization technique. The proposed technique minimizes both single and multi-objective functions like total heat transfer area, total pressure loss function, and the total annual cost of a PFHE. This work proposes a Chaotic Opposition-based Kho-Kho optimization technique to deal with single and multi-objective functions. Various benchmark functions have been assessed to evaluate the capabilities of the proposed techniques, including the Wilcoxon signed-rank test. Finally, the outputs such as total heat transfer area, total pressure loss function, and total annual cost are minimized by the proposed optimization technique, resulting in values of 78.50 m2, 0.051, and 834.64$, respectively.

Numerical investigations and design optimization of cryogenic plate-fin heat exchanger in Electric Arc Furnace using radiative heat transfer model

The most crucial element affecting cryogenic systems’ energy efficiency is heat exchangers. In this article, a model for cryogenic plate-fin heat exchanger (PFHE) under thermal-hydraulic performance with various blends is proposed. To reduce five objective functions total heat transfer rate, total weight, total mass flow rate, number of entropy generating units, and whole annual cost the study carried out the PFHE’s optimal design. This study innovatively focuses on optimizing PFHE design for cryogenic conditions using Opposition Learning with the Beetle Swarm algorithm. The proposed geometry addresses non-uniform temperature distribution, emphasizing thermal-hydraulic properties in various blends. Additionally, a second-order semi-discretization radiative heat transfer approach enhances boiler simulation accuracy. A multi-objective optimization of Opposition Learning with Beetle Swarm (MO-OBBS) optimization approach was suggested in the article for the design of PFHE. Despite the significant potential for renewable energy the low-temperature waste heat treatment process is rarely examined from a sustainability perspective. Consequently, the study proposed a second-order semi-discretization radiative heat transfer method to simulate a furnace using a water heat recovery process. The cooling panel’s numerical analysis was conducted using computed temperature fields. The performance of the various algorithms is compared using the Freidman rank-sum test to determine the statistical significance of the findings obtained. In logarithmic coordinates, the proposed method’s faster convergence is compared to GQB-PSO, SLTLBO, Jaya, CKKO, and OLE-SCA algorithms. The proposed method exhibits a maximum average increase of 115.39% for PFHE design. When the numerical simulation results are compared to measurements of output water temperature, the accuracy is highly improved.

A methodology to reduce the computational effort in 3D-CFD simulations of plate-fin heat exchangers

The analysis of a plate-fin heat exchanger performance requires the evaluation of key parameters such as heat transfer and pressure drop. In this regard, Computational Fluid Dynamics (CFD) can be proficiently adopted, at the design stage, to predict the performance of plate-fin heat exchangers. However, these last are often characterized by a complex geometry, such as in the case of plate exchangers with turbulators, leading to a huge computational effort, which often exceeds the available resources. In this study, a numerical methodology for the simulation of plate heat exchangers is proposed, to bypass the limits imposed by the computational cost. The methodology relies on the simulation of a minimal portion of the exchanger (two plates, one per fluid) characterized by periodic boundary conditions (that mimic the presence of several layers). The total heat exchanged is obtained simply multiplying the calculated heat transfer by the number of plate couples composing the device. Moreover, the two plates allow to calibrate porous media which are adopted to rebuild (in a simplified version) the two fluid circuits of the whole exchanger and obtain the overall pressure drop across the device for both the hot and cold fluids.The proposed approach is validated against experimental data of an oil cooler for automotive application, that is a plate-fin heat exchanger characterized by the presence of turbulators. The numerical outcomes are compared to the experiments in terms of pressure drop and heat transfer for a wide range of volumetric flow rates. Particular attention is devoted to the mesh sensitivity and the adopted computational grid minimizes the number of cells (and, thus, the computational cost), without compromising the accuracy. Moreover, the Reynolds-Stress-Transport turbulence model is accurately selected among the most diffused ones, in order to properly match the test bench data.The proposed methodology allows to reduce of nearly one order of magnitude the total number of cells required for the simulation of the heat exchanger performance. The heat transfer is predicted with high accuracy, i.e. error is always lower than 4%. As for the pressure loss, the deviation compared to the experiments increases up to nearly 15% (for one of the simulated conditions) but it is considered still acceptable.

CFD simulations of plate-fin cross-counter flow compact heat exchanger

CFD simulations of plate-fin cross-counter flow compact heat exchanger

Multivariate multi-objective collaborative optimization of pumped thermal-liquid air energy storage

Pumped thermal-liquid air energy storage (PTLAES) is a novel energy storage system with high efficiency and energy density that eliminates large volumes of cold storage. In this study, three different configurations of PTLAES systems with direct and indirect thermal energy storage were proposed. The “adaptive segmentation-based temperature transfer matrix” method was developed to capture the heat transfer characteristics of multi-stream plate-fin heat exchangers (MPFHEs), which is the key component of the system. To determine the upper limit of the techno-economic performance of the system, single/multi-objective optimization was performed with up to 35 decision variables. Additionally, the “Pareto efficiency” concept was defined to quantify the goodness of a point compared to the Pareto front. The results showed that the irreversible heat transfer and pressure drop in MPFHEs contribute 20.6 %–44.3 % of the total exergy destruction. Therefore, the design of MPFHEs significantly impacts the system performance. Multivariate multi-objective collaborative optimization can significantly improve the optimization results. PTLAES with closed loop indirect thermal energy storage was determined to have the best overall performance, achieving round-trip efficiency of 63.3–70.1 %, levelized cost of storage (LCOS) of 0.162–0.181 $/kWh, and energy density of 122–161 kWh/m3. The optimized PTLAES system can achieve lower LCOS than lithium-ion batteries when the discharge duration exceeds 3.5 h. Furthermore, it was shown that key criteria including round-trip efficiency, LCOS, and energy density can be traded off over a broad design space of different system configurations, parameter combinations, and material choices. This research demonstrated that PTLAES is a promising choice for long-duration energy storage and provided guidance for the design and techno-economic optimization of PTLAES systems.

Heat Transfer and Pressure Drop in Plate Fin Heat Exchangers: A Numerical Approach

An apparatus for transferring thermal energy across an impermeable barrier between two or more fluids is a heat exchanger. The effective transmission of heat from a hot fluid to a cold fluid is its primary goal. The temperature differential between the two fluids directly affects this heat transfer. Using CFD study with FLUENT 2020 R1, the performance characteristics of the compact plate fin heat exchanger's improved surfaces are examined. The simulation of heat transfer and flow encompassed a variety of velocities including completely turbulent regions. The pressure, temperature, and velocity contours were taken from the Fluent simulations. To determine the heat exchanger's flow and heat transfer performance, numerical analysis has been done. Since boundary conditions are crucial to CFD, they have been carefully chosen. The flow field, heat transfer, thickness, and wavelength were all predicted using the software code for a range of air to water velocities. Three distinct wavelengths of numerical simulations for a plate-fin heat exchanger were used in the study (10, 20, and 30). There were changes to the fin thickness, entry locations, and air and water entry velocities. Solid Works and Ansys were used to create the geometry for the three-level fin models that were placed inside the heat exchanger, both with and without a cover. For determining the heat exchanger's geometry and fin isometry, three levels measuring 19.6 mm in height and 53.64 mm in width were constructed. The fins have a thickness of 0.2 to 0.4 mm. As the air and water velocities vary, so does the temperature inside the heat exchanger. Because the topmost layer is a warm stream's flow channel, the temperature rises there, whereas the opposite effect is seen close to the bottom layer. Convection heat transmission to the surroundings and conduction heat transfer through the heat exchanger's side plates are the causes of fluid temperature fluctuations in the depth direction.