Analysis Of Plate Heat Exchanger Research Articles

Numerical simulation and thermodynamic test analysis of plate heat exchanger based on topology optimization

Efficient heat transfer in PHEs relies on optimizing flow distribution to minimize thermal dead zones. Existing studies have predominantly focused on single-phase fluids as working media and employed density-based methods for structural optimization of microchannel heat exchangers at small scales. In this study, the Brinkman term from the porous media flow model is introduced in an innovative manner, along with the utilization of a material density interpolation model, which builds upon the density-based approach. A novel two-phase fluid topology optimization method is proposed, specifically tailored for large-scale PHE operating conditions, resulting in the successful design of a new PHE topology. To compare the performance of the two heat exchangers, finite element simulation, visualization experiments, and thermodynamic performance testing are conducted. The simulation results reveal that the heat transfer capacity of the topological PHE is 810 W with pressure drops of 18.8 kPa, while the dimple PHE exhibits heat transfer capacity of 652 W with pressure drops of 25.9 kPa. Compared to the dimple PHE, the topological PHE demonstrates 24.2 % improvement in heat transfer performance and 27.8 % reduction in pressure drop. The dimensionless comprehensive heat transfer coefficient (j/f) indicates that the overall performance of the topological PHE significantly surpasses that of the traditional PHE. Furthermore, the visualization experiment results demonstrate that the complex texture structure of the topological PHE effectively induces fluid motion, compelling the fluid to flow along the texture direction. This significantly mitigates the issue of uneven flow within the PHE, thus enhancing heat transfer efficiency. Specifically, the topological PHE exhibits inlet–outlet temperature difference of 10.3 °C and pressure drops of 11.2 kPa, while the dimple PHE shows inlet–outlet temperature difference of 6 °C and pressure drops of 12.9 kPa. The findings of this study provide guidance for future research endeavors aimed at evaluating potential solutions to advance heat transfer in PHEs and facilitate the implementation of thermal management strategies.

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.

Performance Analysis of Plate Heat Exchanger with Nanofluid using Milk Pasteurization

Experimentally to analyzed the enhance performance of Plate heat exchanger in milk pasteurization process using nanofluid at different concentration of 0.1%,0.15%,0.2% 0.25% and 0.3%. in this work the nanoparticles like Al2O3 and the base fluid like dematerialized water is used to prepare nanofluid by using two steps method. Exchanger is one of the thermal energy transferring devices, which transfer the heat between different fluids. This is widely used in different application because of its compact in size and higher efficiency compared to other type of heat exchanger. The main focus of using nanofluid is that it has improvement in thermal conductivity. Then the hot fluid as milk and cold fluid as nanofluids are used. The heat transfer rate is increased with increasing the concentration of nanofluid. It conducted by varying operating parameters like mass flow rate of hot milk, mass flow rate of nanofluid, inlet and outlet temperatures of hot milk and inlet outlet temperature of nanofluid. The main objective of this work is to find out mass flow rate and overall, all heat transfer coefficient.

Thermal-hydraulic characteristics of gasketed plate heat exchangers as a preheater for thermal desalination systems

Gasketed plate heat exchangers (PHXs) are frequently used as preheaters in thermal water desalination systems to preheat the intake seawater by recovering heat from the brine and distillate streams. The detailed design and analysis of PHXs as a preheater is not available in the desalination related studies. Rather, the heat transfer coefficients are calculated by simple empirical equations. The current study provides a comprehensive design procedure and analysis of these preheaters. In this regard, a numerical model is developed to investigate the thermal–hydraulic performance of PHXs under various operating conditions. First, the code is validated against the experimental data and then the effect of input parameters is studied. The results show that the feed flow rate and plate chevron angle are very important parameters for the heat transfer coefficient and pressure drop in PHXs. It is shown that the salinity does not affect the HX performance; however, the study also showed that the selection of fouling resistance is critical and it considerably disturbs the design parameters that govern the heat exchanger cost. Finally, the sensitivity analysis is presented to identify the most sensitive input parameters for the thermal–hydraulic performance of the heat exchanger.

Exergy analysis of plate heat exchanger with graphene alumina hybrid nanofluid: experimentation

The water-based hybrid nanofluid is proposed as a cooling agent in a corrugated counter-flow type plate heat exchanger aimed at sub-ambient temperature applications. For this purpose, an experimental investigation has been done with different working fluids. Fluids considered as a coolant are DI water, alumina nanofluid, and alumina-graphene hybrid nanofluid in 80:20 nanoparticle ratio by volume with a total volume concentration of 0.01% dispersed in DI water. Various exergy related performance factors like coolant outlet temperature, coolant exergy rate, irreversibility rate, non-dimensional exergy, and second law efficiency have been considered. The influence of coolant inlet temperature and flow rate on different parameters has been investigated. Coolant outlet temperature, coolant exergy rate, irreversibility rate and non-dimensional exergy augments by 2.5%, 4.8%, 7.5% and 3.5%, respectively. While the second law efficiency degrades using nanoparticles and increasing flow rate and decreases with the coolant inlet temperature.

Exergy analysis of plate heat exchanger with graphene alumina hybrid nanofluid: experimentation

The water-based hybrid nanofluid is proposed as a cooling agent in a corrugated counter-flow type plate heat exchanger aimed at sub-ambient temperature applications. For this purpose, an experimental investigation has been done with different working fluids. Fluids considered as a coolant are DI water, alumina nanofluid, and alumina-graphene hybrid nanofluid in 80:20 nanoparticle ratio by volume with a total volume concentration of 0.01% dispersed in DI water. Various exergy related performance factors like coolant outlet temperature, coolant exergy rate, irreversibility rate, non-dimensional exergy, and second law efficiency have been considered. The influence of coolant inlet temperature and flow rate on different parameters has been investigated. Coolant outlet temperature, coolant exergy rate, irreversibility rate and non-dimensional exergy augments by 2.5%, 4.8%, 7.5% and 3.5%, respectively. While the second law efficiency degrades using nanoparticles and increasing flow rate and decreases with the coolant inlet temperature.

Analysis of plate heat exchanger operating parameters by Taguchi Method

In this study, the heat recovery performance of a plate heat exchanger, which provides air to air heat transfer was investigated. For the experimental set-up, a waste heat recovery device was designed and a heat exchanger was placed in it. Three different operating parameters were selected as fresh and exhaust air inlet temperatures and airflow rates. Three levels for each parameter were determined. The effects of changing parameters on the thermal effectiveness were analyzed by the Taguchi method. L9(33) orthogonal array was used in performing experiments. Results indicate that higher effectiveness can be obtained at low fresh air inlet temperature, low airflow rate, and high exhaust air inlet temperature. In this way, the optimum process parameter combination was revealed. Then, ANOVA was applied in order to detect the significance order of each parameter. The results show that the most important parameter among the others is the airflow rate. Moreover, the confirmation test was performed in order to obtain the optimum parameter combination. The experimental and predicted values are compatible with each other. This experimental study approves that the Taguchi method can be used in improving the exchanger performance.

Modelling and Analysis of Plate Heat Exchangers for Flexible District Heating Systems

Seamless integration of district heating (DH) and power systems implies their flexible operation, which extends their typical operational boundaries and, thus, affects performance of key components, such as plate heat exchangers (PHXs). Despite that the heat transfer in a PHX is regulated by mass flows, flexible operation and demand variations cause shifts in temperature levels, which affects the system operation and must be efficiently accounted for. In this paper, an overall heat transfer coefficient (OHTC) model with direct relation to temperature is proposed. The model is based on a linear approximation of thermophysical components of the forced convection coefficient (FCC). On one hand, it allows to account for temperature variations as compared to mass flow-based models, thus, improving accuracy. On the other hand, it does not involve iterative lookup of thermophysical properties and requires fewer inputs, hence, reducing computational effort. The proposed linear model is experimentally verified on a laboratory PHX against estimated correlations for FCC. A practical estimation procedure is proposed based on component data. Additionally, binding the correlation to one of varying parameters shows reduction in the heat transfer error. Finally, operational optimization test cases for a basic DH system demonstrate better performance of the proposed models as compared to those previously used.

해수냉난방용 판형 열교환기의 최적설계를 위한 수치적 연구

Plate heat exchanger are being applied in the field of OTEC (ocean thermal energy conversion) and SWAC (seawater air conditioning) system. This study is to analyze numerically the heat transfer and pressure drop characteristics by using solid works flow simulation in order to offer optimum design data of plate heat exchanger. Plater heat exchanger proposed in this study is four types. The geometric design parameters of plate heat exchanger are a channel space, a flow orientation, a plate array, the flowrate of working fluid and so on. The main results for numerical analysis of plate heat exchangers are summarized as follows. Heat transfer performance for the channel space of 2.4 mm shows the highest value compared to other spaces. And, the Type 4 plate heat exchanger in Table 2 is the highest performance. From the pressure drop characteristics of plate heat exchanger, the channel space of 3.2 mm shows the lowest value. And Type 1 plate heat exchanger in Table 2 is the lowest pressure drop.

The Analysis of Plate Heat Exchanger in Central Heating Regulation of Indirect Connection Hot Water Heating System

Plate heat exchanger with unique advantages become dominant heat exchange equipment in heating engineering. But there is no heating regulation formula of plate exchanger applying in indirect connection hot water heating central heating regulation. This paper analysis the condition that the heating user’s system adopts quality regulation method and the hot water network system adopts quality-flow regulation method, obtain the regulation formulas of plate exchanger applying in indirect connection hot water heating central heating regulation, provides reliable theory basis on the operation regulation, energy –saving testing, etc. for indirect connection central heating system.

Thermal performance analysis of plate heat exchanger with different configurations for the heat recovery system in buildings

Due to the scarcity of conventional energy sources, a lot of efforts need to be taken regarding energy conservation in the buildings, including heat recovery of air ventilation systems. The present paper focuses on new methods to improve the thermal performance of the heat recovery system by investigating the heat transfer characteristics and the flow development in a flat-plate heat exchanger (FPHE) using three different rib-grooved surfaces (trapezoidal, triangle and semi-circular), the numerical simulations were carried out for uniform wall heat flux equal to 290 W/m2 for air as the working fluid, the Reynolds number varies from 500 to 2000 for three different channel heights. The numerical results indicated that, rib-grooved surfaces have a significant impact on heat transfer enhancement with an increase in the pressure drop through the channel. The effect of rib-grooved patterns on the heat transfer and the fluid flow is more significant in a narrow channel especially for trapezoidal and triangle corrugated surfaces, because they have sharp edges. Based on the present research, the FPHEs with the added rib-grooved surfaces are recommended to provide an efficient and compact heat recovery system. Moreover, it was found that by applying the new design, a considerable amount of energy and power could be saved.

A new model for plate heat exchangers with generalized flow configurations and phase change

A new model has been developed for the analysis of plate heat exchangers with multi-fluid, multi-stream and multi-pass configurations. The model divides the entire heat exchanger into multiple slices in the direction of fluid flow. For the channels in each slice, the wall temperatures are assumed to be constant such that each channel can be solved without the need of knowing the fluid condition in the adjacent channels. In the top level, all the slices are iterated using a successive substitution approach. The model is capable of handling both single-phase and two-phase flow. In general, plate heat exchangers are used with two to three fluids, but the model is capable of handling more than three fluids wherein each fluid can undergo phase change. The model was verified against the P-NTU closed form expressions for single-phase flow in plate heat exchangers with various flow configurations. The model was validated against in-house experimental data for single-phase water, two-phase ammonia and R22 boiling. The effect of discretization and the speed up on multiple cores was investigated.

Special edition of Applied Thermal Engineering

A new model has been developed for the analysis of plate heat exchangers with multi-fluid, multi-stream and multi-pass configurations. The model divides the entire heat exchanger into multiple slices in the direction of fluid flow. For the channels in each slice, the wall temperatures are assumed to be constant such that each channel can be solved without the need of knowing the fluid condition in the adjacent channels. In the top level, all the slices are iterated using a successive substitution approach. The model is capable of handling both single-phase and two-phase flow. In general, plate heat exchangers are used with two to three fluids, but the model is capable of handling more than three fluids wherein each fluid can undergo phase change. The model was verified against the P-NTU closed form expressions for single-phase flow in plate heat exchangers with various flow configurations. The model was validated against in-house experimental data for single-phase water, two-phase ammonia and R22 boiling. The effect of discretization and the speed up on multiple cores was investigated.

Alternative approach in thermal analysis of plate heat exchanger

This paper presents alternative approach in heat transfer analysis of plate heat exchangers. In order to obtain heat transfer rate and effectiveness values of plate heat exchanger, neural network (NN) approach was used. Experimentally, system used in plate heat exchanger for heating and cooling applications was designed and constructed. Experimental data were used for training and testing network. The training and validation were performed with good accuracy. The correlation coefficient obtained when unknown data were applied to the networks was 0.9994 for heat transfer rate and 0.9976 for effectiveness, which is very satisfactory. Using the weights obtained from the trained network, a new formulation is presented for determination of heat transfer rate and effectiveness. This formulation can provide simplicity in thermal analysis of plate heat exchanger. The presented procedure can also help to heat exchanger designer and manufacturer.

Some Aspects of Sizing Plate Heat Exchangers Used in District Heating

ABSTRACT The sizing aspects of plate heat exchangers, which are used more and more frequently in district heating, are different from those of the shell-and-tube or shell-and-coil heat type exchangers used earlier. While in the selection of the earlier used heat exchangers thermal aspects played the most important part because of structural reasons, for plate heat exchangers both thermal and hydraulic aspects are important. This article • discusses the results of the thermal and hydraulic analysis of plate heat exchangers; • describes the changes in the number of heat exchanger plates as a function of the nominal temperature and pressure drop of the heating and heated fluids; • presents examples for the use of the hydraulic resistance of heat exchangers.

Dynamic analysis of plate heat exchangers with dispersion in both fluids

Based on a dispersion model, an extensive analysis is presented for counterflow plate heat exchangers, which takes the deviation from ideal plug flow into consideration to predict the response due to temperature transients. The analysis also incorporates solid longitudinal conduction and solid as well as fluid heat capacities, and simulates the exit temperatures of both fluids for any given arbitrary temperature transient at the inlet(s). It is found that the ‘phase lag effect’, which is a special characteristic of plate exchangers, plays a significant role in the dynamic regime. The examples are presented for step and sinusoidal response and the effect of U- and Z-type configurations has been discussed. The method is based on the Laplace transform and it utilizes numerical inversion of the Laplace transform. The results lead to the conclusion that the effect of flow maldistribution and ‘phase lag’ plays an important role, particularly when the decreasing flow velocity in the gasket ports is taken into consideration.

Exergetic analysis of plate heat exchanger in presence of axial dispersion in fluid

This paper presents an exergetic analysis of a single pass counterflow plate type heat exchanger for cryogenic applications. The special focus of the analysis is the study of the effect of axial dispersion which takes the flow maldistribution into consideration. It is found that with unutilized exergy fraction as the figure of demerit the exergetic performance of the heat exchanger can be consistently presented without the ‘paradox’ which has been observed by many investigators. The axial dispersion is found to reduce the exergetic performance and so does the frictional pressure drop of the fluids. This makes it possible to identify a minimum irreversibility corresponding to a given level of dispersion. It has been observed that over a relatively broad zone near the optimum NTU the change in exergy loss is small, providing more flexibility for the designer of the heat exchanger to alleviate the penalty for exergy loss, which is particularly severe in the cryogenic regime.

プレート式熱交換器の動特性

プレート式熱交換器の動特性