Performance Of Plate Heat Exchanger Research Articles

Flow and heat transfer characteristics and comprehensive evaluation of asymmetric plate heat exchangers for centralized heat supply

The structure of flow channel on both sides of the conventional plate heat exchanger(CPHE) is symmetrical. CPHEs are struggle to perform efficiently when subjected to asymmetric working conditions in district heating system. In order to improve the performance of plate heat exchangers under asymmetric conditions, asymmetric plate heat exchangers(APHEs) was designed. In this paper, APHEs were parameterized by asymmetric factor a. An evaluation index η for APHE is introduced to quantitatively analyze APHE’s suitability in district heating system. Numerical simulations were performed to investigate the heat transfer characteristics and resistance characteristics of the APHEs with 11 asymmetric factors a. Through using η, APHEs with the best comprehensive performance were found, when the flow ratio is 1.50, 1.75, 2.00, 2.25, 2.50 and 2.75. In flow ratio, APHEs provide the comprehensive performances with an improvements of 28 %, 39 %, 54 %, 65 %, 72 % and 83 % compared with CPHEs. Correlations equation for the average Nu and f on both hot and cold sides of the APHEs were established. There exists a correlation between Nu and f for the APHEs with respect to asymmetry factor a and flow ratio.

Optimizing thermal efficiency: Advancements in flat plate heat exchanger performance through baffle integration

Compact heat exchangers have been gaining popularity in many industrial applications. Various types of passive turbulising structures such as corrugations, protrusions and ribs are introduced in the flow path to increase the effective heat transfer area and the level of turbulence in the flow path. This study investigates the impact of introduction of baffles on the performance of PHEs in terms of flow characteristics, pressure drop, and heat transfer. Two distinct types of baffle structures, namely wedge and aerofoil configurations, were introduced at varying numbers - 1, 3, and 5. An extensive experimentation is conducted for a FPHE in a thermal power plant of 500 × 2 MW and various flow and thermal parameters are measured. Computational Fluid Dynamics is utilized in this study to find the optimum baffle configuration. A detailed validation study is executed to obtain the correct computational algorithm, that is the right mesh count, optimum turbulence model, and precise numerical algorithm by comparing the numerical results with the available experimental results. Wedge- type baffles create increased turbulence and pressure drop, while aerofoil-type baffles minimize stagnation and exhibit lower pressure drop. Both baffle configurations lead to a substantial increase in heat transfer, with the 5-wedge-baffle setup showing the highest up to a 55% enhancement of Nusselt number. The Performance Evaluation Criterion (PEC) of wedge and aerofoil type is about 1.24 to 1.3 and 1.22 to 1.24 to that of conventional one respectively.

Experimentation with different alumina hybrid (50:50) suspensions as coolant on plate heat exchanger performance

Experimentation with different alumina hybrid (50:50) suspensions as coolant on plate heat exchanger performance

Characterization of brazed plate heat exchanger performance based on experimental and coupled heat-fluid-solid numerical simulation

A physical and mathematical model of a complete brazed plate heat exchanger (BPHE) with three layers and two channels was presented. Experiments were conducted on the BPHE using water as the fluid, and the experimental results were compared with the simulation results in terms of heat transfer efficiency and pressure drop. An analysis of the relationship between the Nusselt number and drag factor of the BPHE at a specific Reynolds was also provided, with a focus on identifying any errors. Furthermore, the internal flow and heat transfer characteristics of the BPHE were analyzed. The thermal stress and lifetime of the BPHE at different operating temperatures were simulated by using the heat-flow-solid coupling method. The results reveal that the presence of stress concentration points and the thermal stress increases while the lifetime decreases with the rise in operating temperature. In summary, the study demonstrates that the BPHE experiences stress concentration points and their intensity varies with the working temperature, thereby affecting the overall lifetime of the BPHE.

Optimizing the effect of micro-surface on the thermal hydraulic performance of plate heat exchanger

This research used electrochemical etching as a new method for generating micro surfaces in an effort to improve the thermal–hydraulic performance of a plate heat exchanger (PHE). This technique has significant advantages in terms of producing evenly structured surfaces and enabling exact size control compared to other techniques such as sandblasting and electroplating. Thus, it has great potential to be a pioneer in the industrial implementation of micro surface on heat exchangers. This work is the first to examine the impact of optimum roughness on both the Nusselt number (Nu) and the Performance of Evaluation Criterion (PEC) of PHE using a multi-objective genetic algorithm. In order to do this, several microstructure surfaces were generated on the PHEs, with average roughness values ranging from 0.65 to 1.51 μm. The impact of these microstructure surfaces on heat transfer and pressure drop was experimentally investigated through heat transfer experiments conducted at Reynolds numbers (Re) ranging from 3,000 to 12,500. The findings reveal that the introduction of microstructure surfaces leads to a noteworthy enhancement of 10 % to 18 % in the overall heat transfer coefficient (OHTC) across all experimental scenarios. Conversely, the friction factor experienced an increase of 28 % to 53 % compared to a smooth surface. PEC values ranged from 1.05 to 1.21, showing a superior heat transfer performance over a marginal pressure drop increase. Furthermore, the microstructure surfaces demonstrated significantly improved values of 0.23 to 0.32 for the Number of Transfer Units (NTU) and 0.18 to 0.26 for effectiveness, in comparison to the smooth surface. This corresponds to an enhancement of 9.7 % to 18.5 % and 7.2 % to 16.4 %, respectively. In addition, a multi-objective genetic algorithm determined that an optimal roughness value of Ra = 1.1 μm achieves a balance between maximizing Nu and PEC.

Analysis of plate heat exchangers in binary flashing cycle using low-temperature heat source

The utilization of low-temperature heat sources represents an efficient technology that has the potential to significantly reduce both energy consumption and greenhouse gas emissions. Among the various technologies that harness low-temperature heat sources, the binary flashing cycle (BFC) stands out as a promising option. The application of the BFC is highly dependent on the thermal–hydraulic performance of the heat exchangers, which underscores the critical importance of effective heat exchanger design. The popular used plate heat exchangers (PHEs) are selected as suitable candidates for BFC system. Detailed thermodynamic, hydraulic, and thermal design models for the BFC system are developed for PHEs. The effects of geometrical parameters of the evaporator and condenser on the heat exchanger area and pressure drop are investigated simultaneously. It is revealed the increments in plate width and plate number leads to an augmentation of the heat exchanger area while concurrently reducing the pressure drop. Moreover, an optimal plate space is identified, which minimizes the pressure drop. Additionally, it is observed that the evaporator and condenser exhibit superior thermal–hydraulic performance, when the corrugation angle is approximately 60°. Furthermore, a multi-objective optimization approach employing Non-dominated Sorting Genetic Algorithm-II (NSGA-II) is utilized to determine the optimal geometrical parameters. In order to classify the alternatives to the obtained Pareto front, the technique of order preference by similarity to the ideal situation (TOPSIS) is applied. It should be noted that the decision variable is influenced by the weight factor assigned to the objective function. The optimal plate width, channel spacing, plate number, and chevron angle range from 0.3–0.56 m, 3.5–5.9 mm, 20–24, 68–74°, 0.20–0.75 m, 3–7 mm, 30–32, and 56–59°, respectively. The study provides valuable insights for decision-makers involved in engineering application regarding the thermal–hydraulic performance of plate heat exchangers within the BFC system.

Evaluation of Fluid Flow Velocity Variations on the Plate Heat Exchanger Performance

Heat exchanger expected to high effectiveness of heat transfer. Type of plate heat exchanger was more efficient compare to another heat exchangers in industrial applications with pressure less than 30 bar. The increased velocity of cold fluid flow has an impact to increase the performance of heat exchanger by heat transfer rate (Q), heat transfer coefficient (U), and the effectiveness of heat exchanger (ε). The increased velocity of cold fluid flow also incresing the heat transfer rate. The study carried out by variation of the cold fluid velocity at 0.03 m/s, 0.037 m/s, 0.045 m/s, 0.051 m/s and 0.059 m/s. Inlet hot fluid temperature (Th,i) at 45°C and cold fluid temperature (Tc,i) at 27°C constant. The results shows Q value from the original 1570.71 Watt to 1916.16 Watt on the hot side and 1751.89 Watt to 2187.01 Watt on the cold side. The U value from the original 1180.46 W/m2.°C becomes 1408,75 W/m2. °C. The ε value increased from 60.33% to 75.69%. The increasing of cold fluid velocity directly proportional to the the heat transfer rate (Q) and performance of the plate heat exchanger. This Phenomenon due to the faster circulation of the cold fluid, which causes the cold fluid to quickly return to its initial temperature (Th,i), an than increasing the plate heat exchanger's performance.

Effect of flow path on the performance of plate heat exchanger with chevron shape

Effect of flow path on the performance of plate heat exchanger with chevron shape

Experimental investigation of the effect of hydrophobic coating on heat transfer and gasketed plate heat exchanger performance

In this study, the effect of hydrophobicity on the plate surface on heat transfer, pressure drop, and pump power was investigated without changing the existing designs of gasketed plate heat exchangers (GPHEs). The wet surfaces of the plate were coated with carbon-based polymer solutions with four different hydrophobic groups, that is, FEP, FH3, FH7, and FH10. To increase the hydrophobicity of the FEP material, a new coating solution was synthesized by adding 3, 7, and 10 wt.% h-BN nanoparticles. Heat transfer, pressure loss, and pump power performances of heat exchangers with hydrophobic surface coating were tested at five different Reynolds numbers and compared with the uncoated heat exchanger performance. Also, the efficiency analysis of the GPHE under different hydrophobic conditions was carried out. As a result, the addition of 3 and 7 wt.% h-BN nanoparticles increased the contact angle. However, the addition of 10 wt.% h-BN decreased the contact angle as it increased the rough structure and film thickness on the surface. It was determined that the heat exchanger efficiency increased proportionally with the increase in hydrophobicity. While the highest heat exchanger efficiency value was 0.525 in FH7 coated. However, it was found that there was a 25.6% decrease in heat transfer of FH7 coating compared to uncoated exchanger. The pressure drop of the FH7 surface-coated heat exchanger with the highest hydrophobicity was 207.6% lower than that of uncoated heat exchanger. Energy savings of approximately 41% were achieved in FH7 coated compared to uncoated heat exchangers. It has been emphasized that heat transfer in GPHE systems should be evaluated together with pressure drops and local losses. It was found that the use of hydrophobic surface coating on plates in heat exchangers will contribute to the development of heat exchanger designs, reducing pump costs, and energy consumption.

Effect of plate spacing and inclination angle over the thermal performance of plate heat exchanger working with novel stabilized polar solvent-based silicon carbide nanofluid

In this work, the overall thermal performance of a commercial corrugated plate heat exchanger has been conducted for the first time by varying the three different plate corrugated angles (30°, 45°, 60°) and variable plate spacing (from 5 mm to 20 mm) working with polar solvent-based novel Silicon carbide (SiC)/DI Water nanosuspension as a coolant by focusing potential industrial application. This study aimed to identify the enhancement in thermal performance of plate heat exchanger by evaluating its overall heat transfer coefficient, pressure drop, pumping power, and exergetic efficiency by utilizing SiC/DI water nanofluid of varying volume concentration (0.20 %, 0.40 %, 0.60 %, 0.80 %, 1.00 %, 1.20 %, and 1.40 %) at ambient condition (T0 = 27 ° C), and fixed volumetric flow rate (3 L/min) for both (nanofluid and milk) sides. From the experimental results, the optimum volume concentration for the coolant was found as 0.60 %, which yields a significant enhancement in the overall heat transfer coefficient ratio by approximately 51 %, 42 %, and 38 % for 60°, 45°, and 30° corrugated plate angle respectively. The significant enhancement for 0.6 % of optimum volume concentration and 5 mm plate spacing has been reported as the best possible option at which the pumping power ratio, performance index ratio, and exergetic efficiency ratio attained the highest enhancements.

The effect of plate corrugation on the wetting performance of plate heat exchanger for desalination

The effect of plate corrugation on the wetting performance of plate heat exchanger for desalination

Effect of geometrical parameters on the performance of plate heat exchanger using milk- water as medium fluids in the channels

The present study deals with the selection of optimal geometrical parameters of the plate heat exchangers (PHEs) based on the results obtained by 3-D numerical simulation of flow and heat transfer between milk and water. The investigations are carried out for chevron angle, β = 30°, 45° & 60°, pitch to depth ratio of corrugation, p/d = 2, 2.25, 2.587 & 3.333, enlargement factor, φ = 1.07, 1.197, 1.504, 1.643, 1.789 & 2.094, hydraulic diameter, Dh = 3.99, 4.26, 4.47, 4.77, 5.01 & 5.48, Reynolds number, Re = 60 to 1850, and Prandtl number, Pr = 3.69 to 17.7 using water-milk as well as water-water combinations in the exchanger. For enriching the computational work, the simulated results are validated with present experimental results as well as with previously reported experimental work. Based on the experimental validation, laminar and turbulent models are suggested for various ranges of Reynolds number of water and milk as working fluids. The thermo-hydraulic performance of PHE is evaluated using the JF factor, showing that the chevron angles, β = 30° and β = 60°, perform better respectively in laminar and turbulent regions for both milk and water as cooling fluids. In addition to that, the pitch-to-depth ratio, p/d = 2.25, gives optimum performance for chevron angle, β = 60° plates PHE. Based on the numerically simulated results, the correlations of Colburn and friction factors are proposed in terms of chevron angle, enlargement factor, p/d ratio, and Re for evaluating the thermo-hydraulic performance of the PHEs.

Experimental investigation of the effect of air bubbles injection on the performance of a plate heat exchanger

• Air is injected in cold water to enhance the performance of plate heat exchanger . • A first PHEX performance test at various air and hot water flow rates is reported. • NTU and effectiveness are enhanced by up to 12.4 and 14.6 %, respectively. • Entropy generation rate increases up to 4.1 W/K with air bubble injection. • Witte-Shamsundar efficiency reaches a maximum of 96.9% for lowest water flow rate. Injection of sub-millimeter scale air bubbles into liquid flows has been recognized recently as an effective method for thermal performance enhancement of heat exchangers. However, no studies have been reported so far on air injection into the cold liquid stream of plate heat exchangers (PHEX). This approach is investigated experimentally in the present study for the first time in PHEXs to map the energetic and exergetic performance characteristics of a typical PHEXs in terms of the number of transfer units (NTU), effectiveness, entropy generation number, augmentation entropy generation number, rational effectiveness, and Witte-Shamsundar efficiency. Air (150–840 L/h) and hot water (280–880 L/h) streams are mixed in a T-junction mixing chamber before entering the PHEX as a two-phase flow. The results show a remarkable increase in NTU by up to 12.4% due to injected air bubbles, whereas the effectiveness increases by up to 14.6%. On the other hand, considerable increments in entropy generation rate are noticed, reaching a maximum of 4.1 W/K, but this increment was less than 3 folds for most examined cases. Overall, the Witte-Shamsundar efficiency, representing the combined energetic-exergetic performance, reached a maximum of 96.9% at air and hot water flow rates of 350 and 280 L/h, respectively.

The effect of plate size and corrugation pattern on plate heat exchanger performance in specific conditions of steam-air mixture condensation

The results of mathematical modelling and experimental study of plate heat exchangers (PHEs) in steam-air mixture condensation are presented. The mathematical model is validated by test data for PHE in the industry and for five experimental samples with corrugation angles, 30°, 45°, and 60° and corrugation heights 5, 7.5 and 10 mm. With no limited pressure drop in PHE, its heat transfer area can be decreased up to 4 times with the plate's corrugations angle of 60°. When pressure drop on the side of condensing stream is limited, at a small mass fraction of air, PHE with corrugated plates' heat transfer area can be smaller than in PHE assembled from flat plates about 1.5 times ± 11% at channels of different corrugations geometries. For commercially produced plate-and-frame PHE, the pressure losses at channel entrance and distribution zones should be accounted. For plates with a corrugations angle of 60°, their share in total pressure drop can be from 7% up to 39.3%, while at a corrugations angle of 30°, up to 59%. The final choice of corrugation angle and height for plates designed for specific duty can be made by solving a future optimisation problem with a developed mathematical model.

Numerical prediction of heat transfer performance of plate heat exchanger based on experimental data assimilation to calibrate turbulence model constants

• Apply Data Assimilation to the study of heat transfer characteristics. • Use the ensemble Kalman filter to calibrate turbulence model constants. • Realize the perfect integration of experimental and numerical research. • The application of Data Assimilation in engineering is expanded. The heat transfer effect of plate heat exchangers is different due to its various plate structures. To accurately predict the heat transfer characteristics of a plate heat exchanger, this paper makes an important attempt to apply data assimilation technology, namely the data-driven model constant optimization method, to the study of the flow and heat transfer characteristics of a plate heat exchanger. Based on the experimental data, the ensemble Kalman filter algorithm is used to calibrate turbulence model constants and predict the heat transfer performance of a plate heat exchanger. The results show that the data assimilation technology maximizes the value of experimental data, realizes the perfect integration of experimental research and numerical simulation research, and gives full play to the advantages of experimental research and numerical simulation research of plate heat exchangers. At the same time, the reliability of predicting heat transfer characteristics of a plate heat exchanger is improved, the application of data assimilation in engineering is expanded, and the application potential of data assimilation in future turbulence research is highlighted.

Experimental investigation of the performance of the plate heat exchanger using (Multi-Walled Carbon Nanotubes–Al2O3/water) hybrid nanofluid

Heat exchanger development is one of the issues where study continues because of its relevance in a variety of sectors. The utilization of hybrid nanofluids as a working fluid requires more investigation. The performance of plate heat exchangers (PHEs) employing hybrid nanofluid (multi-walled carbon nanotubes (MWCNTs)–Al2O3/water) with varying volume concentrations was investigated in an experimental investigation. The current study makes use of an Armfield PHE (HT32) with an Armfield heat exchange service unit (HT30X). In this investigation, three-volume concentrations were employed (0.5%, 1%, and 2%). A (MWCNTs/water) nanofluid with a volume concentration of 2% was prepared to compare with the hybrid nanofluid. The heated fluid (distilled water and nanofluids) has a Reynolds number of 100 to 800. By monitoring the variables, the overall heat transfer coefficient, pressure drop, friction factor, mean Nusselt number, and effectiveness could be computed. Based on the concentration of nanoparticles in the base fluid, the experimental findings revealed that hybrid nanofluids had a substantial impact on the heat transfer process. With increasing volume concentration, the overall heat coefficient, Nusselt number, and effectiveness increase. The volume concentration of nanoparticles determines the increase in the overall heat coefficient from 6% to 97% compared to pure distilled water. The increase in the hybrid nanofluids volume concentration leads to an increase in the pressure drop and the friction factor. The Nusselt number and the effectiveness increase with the increase of the volume concentrations and Reynolds number. Comparing the performance of the hybrid nanofluid and monoparticles nanofluid with the same concentration ratio, an improvement in performance was seen using hybrid fluids. An empirical correlation to calculate the Nusselt number for the hybrid nanofluid (MWCNTs–Al2O3/water) with the ratio of the particles (50:50) is obtained. It is possible to discover acceptable agreement by comparing the current study to earlier publications on this subject.

Thermal performance of new type plate heat exchanger with spring turbulence generator using nanofluid flow

ABSTRACT In this study, a new design has been developed to increase the thermal performance of a plate heat exchanger. In the developed design, springs are placed on the heat exchanger plates at an angle of 45°. In this study, which aims to improve heat transfer by increasing turbulence, nanoparticles were also used to increase the heat transfer coefficient of the heat transfer fluid. The nanoparticles used are Al2O3 and CuO in three different densities. The performance factor of the system was calculated experimentally with these fluids entering the heat exchanger at six different speeds. The highest performance factor obtained was 1.33, and it was obtained by using 1% mass ratio Al2O3 nanoparticles. The highest value for CuO, the other nanoparticle used, was determined as 1.27. The highest increases in heat transfer are 60.7% and 56.5% for Al2O3 and CuO, respectively.

The influence of plate corrugation geometry on heat and mass transfer performance of plate heat exchangers for condensation of steam in the presence of air

Processes of steam condensation in the presence of air, as non-condensable gas, was studied in experiments with the models of plate heat exchanger (PHE) channels formed by plates with corrugations of different geometry. Validity of the developed mathematical model for the calculation of local process parameters is confirmed, and it is used to facilitate the analysis of experimental results. Sets of experiments were performed on five samples modelling PHE channel main corrugated field. The corrugations angle to plate vertical axis in three experimental samples was 30°, 45° and 60° at the same corrugations’ height of 5 mm. Another two samples had corrugations height 7.5 mm and 10 mm at the same corrugations angle 60°. Various effects of plate sizes and geometrical parameters of corrugations on the performance of PHE as a condenser for steam–air mixture and local process parameters profiles are discussed. Presented analysis shows that the specified process conditions on temperature and pressure drop in PHE can be satisfied by varying corrugations angle and channel spacing at plates of different lengths. To maintain the same temperature program with a decrease of plates corrugation angle from 60° to 30° require the plates with a length bigger from 2 to 2.6 times, depending on specific process conditions. These plate parameters are recommended for use as variables in solving the problem of PHE plate geometry optimisation with the use of the proposed mathematical model.

Experimental investigation on frequency pulsation effects on a single pass plate heat exchanger performance

AbstractThis paper investigates combined heat transfer improvement methods. These methods include introducing pulsating flow, adding nanofluids, and manipulating the flow's characteristics in a corrugated plate heat exchanger. Tests are carried out with multi‐walled carbon nanotube (MWCNT), graphene nanoplate (GNP), and a mixture of GNP and MWCNT meeting the requirement of 0.01% nanofluids volume fraction and exposed to pulsation. Results demonstrated that the use of pulsating frequencies from 0 to 30 Hz of GNP‐water, MIX nanofluids–water, and MWCNT–water nanofluids with a constant concentration of 0.01 wt% leads to a significant improvement in heat transfer. Using pure water at frequency f = 0 Hz as a benchmark, the Nusselt number of the mixture nanofluid increases by 15.2%, 27.5%, 40.4%, and 52.8% with the increase of frequency pulsation from 0 to 30 Hz with a slight effect on the pressure‐drop at this low used constant nanofluid concentration = 0.01%. The highest Nusselt number value for GNP‐water nanofluid improved by an amount of 58.3% at the highest frequency compared with pure water at f = 0 Hz.

Numerical analysis of thermal performance of heat exchanger: Different plate structures and fluids

Due to compact size, high power density, low cost and short construction time, the small modular reactors are considered as one of the candidate reactors, in which the power generation system is important with a compact heat exchanger for modular construction. Therefore, the effect of plate structure and nature of the working fluid on the thermal performance of plate heat exchanger are analyzed for the design of compact and efficient heat exchanger. The heat transfer rate, temperature counters, velocity vectors, and pressure drop have been optimized and investigated using FLUENT. The Nusselt number has been calculated for the corrugated and flat plate heat exchanger to validate the convective heat transfer. The numerical results are agreed well with correlation within deviation of ~5-7%. The performance of heat exchanger can be improved by controlling the mass-flow rate, and temperature of working fluid. The corrugation plate heat ex-changer increases the heat transfer rate 20% and effectiveness 23%, respectively, as compare to flat plate heat exchanger when the working fluid is water. In the case of air, heat transfer rate, and effectiveness are about 10% and 9%, respectively. The results show that the corrugated plate heat exchanger is more effective than the flat plate heat exchanger because corrugation pattern enhances the turbulence of fluids, which further increase heat transfer rate and coefficient. The selection of the working fluid and structure of the plate must be considered carefully for efficient and compact design of heat exchanger.