Статті в журналах: "Heat exchangers network"

1

Ge, Yu Lin, Ping Wang, Sheng Qiang Shen, and Jun Liang Xu. "Synthesis Method of Heat Exchanger Network for Distillation Device." Advanced Materials Research 199-200 (February 2011): 1509–12. http://dx.doi.org/10.4028/www.scientific.net/amr.199-200.1509.

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Mathematical programming model for synthesis of heat exchanger network for distillation unit is established. MINLP problem for heat exchanger network is solved by branch-bound method. Two kinds of heat exchanger network with splitting stream and without splitting stream are obtained. 142 heat exchangers, 8 coolers and 4 heaters are needed in the heat exchanger network without splitting stream. 34 heat exchangers, 8 coolers, 4 heaters, 11 splitters and 11 mixers are needed in the heat exchanger network with splitting stream. The matching situation including heat load, heat exchange area, duty of utilities, flow fraction of splitting, temperature of inlet and outlet, etc. for cold and hot streams in the heat exchanger network with splitting stream is presented in detail, Analysis the relationship between total heat exchange area, total heat load, total capital cost and annual operation cost of the heat exchanger network. Taking the number of heat exchangers and operational flexibility of heat exchange network into consideration, the heat exchanger network with splitting stream is suggested to be selected.

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2

Ramezanpour Jirandeh, Reza, Mehrangiz Ghazi, Amir Farhang Sotoodeh, and Mohammad Nikian. "Plate-fin heat exchanger network modeling, design and optimization – a novel and comprehensive algorithm." Journal of Engineering, Design and Technology 19, no. 5 (January 11, 2021): 1017–43. http://dx.doi.org/10.1108/jedt-07-2020-0262.

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Purpose The purpose of this paper is to present a novel and applied method for optimum designing of plate-finned heat exchanger network. Considering the total annual cost as the objective function, a network of plate-finned heat exchanger is designed and optimized. Design/methodology/approach Accurate evaluation of plate-finned heat exchanger networks depends on different fin types with 10 different geometrical parameters of heat exchangers. In this study, fin numbers are considered as the main decision variables and geometrical parameters of fins are considered as the secondary decision variables. The algorithm applies heat transfer and pressure drop coefficients correction method and differential evolution (DE) algorithm to obtain the optimum results. In this paper, optimization and minimization of the total annual cost of heat exchanger network is considered as the objective function. Findings In this study, a novel and applied method for optimum designing of plate-finned heat exchanger network is presented. The comprehensive algorithm is applied into a case study and the results are obtained for both counter-flow and cross-flow plate-finned heat exchangers. The total annual cost and total area of the network with counter-flow heat exchangers were 12.5% and 23.27%, respectively, smaller than the corresponding values of the network with cross-flow heat exchanger. Originality/value In this paper, a reliable method is used to design, optimize parameters and the economic optimization of heat exchanger network. Taking into account the importance of plate-finned heat exchangers in industrial applications and the complexity in their geometry, the DE methodology is adopted to obtain an optimal geometric configuration. The total annual cost is chosen as the objective function. Applying this technique to a case study illustrates its capability to accurate design plate-finned heat exchangers to improve the objective function of the heat exchanger network from the economic viewpoint with the design of details.

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3

Zhang, Yin, Yinping Zhang, and Xin Wang. "Inverse Problem Method to Optimize Cascade Heat Exchange Network in Central Heating System." International Journal of Energy Optimization and Engineering 9, no. 3 (July 2020): 62–82. http://dx.doi.org/10.4018/ijeoe.2020070105.

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In central heating systems, heat is often transferred from heat source to users by the heat network where several heat exchangers are installed at the heat source, substations, and terminals. In this article, the mathematical optimization model of the cascade heat exchange network with three-stage heat exchangers in a series is established. The aim is to maximize the cold fluid temperature for a given hot fluid temperature and overall heating capacity, the optimal heat exchange area distribution, and the medium fluid flow rates are determined through an inverse problem and variation method. The results show that the heat exchange areas should be distributed equally for each heat exchanger. It also indicates that in order to improve the thermal performance of the whole system, more heat exchange areas should be allocated to the heat exchanger where flow rate difference between two fluids is relatively small.

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4

Wang, Bohong, Jiří Jaromír Klemeš, Petar Sabev Varbanov, and Min Zeng. "An Extended Grid Diagram for Heat Exchanger Network Retrofit Considering Heat Exchanger Types." Energies 13, no. 10 (May 24, 2020): 2656. http://dx.doi.org/10.3390/en13102656.

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Heat exchanger network (HEN) retrofit is a vital task in the process design to improve energy savings. Various types of heat exchangers such as shell and tube, double-pipe, compact plate, and spiral tube have their working temperature ranges and costs. Selecting suitable types of heat exchangers according to their temperature ranges and costs is a crucial aspect of industrial implementation. However, considering the type of heat exchangers in the HEN retrofit process is rarely seen in previous publications. This issue can be solved by the proposed Shifted Retrofit Thermodynamic Grid Diagram with the Shifted Temperature Range of Heat Exchangers (SRTGD-STR). The temperature ranges of six widely used heat exchanger types are coupled in the grid diagram. This diagram enables the visualisation of identifying the potential retrofit plan of HEN with heat-exchanger type selection. The retrofit design aims to minimise utility cost and capital cost. An illustrative example and a case study are presented to show the effectiveness of the method.

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5

Rauch, Martina, and Antun Galovic. "Energy analysis of heat exchanger in a heat exchanger network." Thermal Science 22, no. 5 (2018): 1999–2011. http://dx.doi.org/10.2298/tsci171231216r.

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For many years now, heat exchanger optimization has been a field of research for a lot of scientists. Aims of optimization are different, having in mind heat exchanger networks with different temperatures of certain streams. In this paper mathematical model in dimensionless form is developed, describing operation of one heat exchanger in a heat exchanger network, with given overall area, based on the maximum heat-flow rate criterion. Under the presumption of heat exchanger being a part of the heat exchanger network, solution for the given task is resting in a possibility of connecting an additional fluid stream with certain temperature on a certain point of observed heat exchanger area. The connection point of additional fluid stream determines the exchanging areas of both heat exchangers and it needs to allow the maximum exchanged heat-flow rate. This needed heat-flow rate achieves higher value than the heat-flow rate acquired by either of streams. In other words, a criterion for the existence of the maximum heat-flow rate, as a local extremum, is obtained within this mathematical model. Results of the research are presented by the adequate diagrams and are interpreted, with emphasis on the cases which fulfill and those which do not fulfill the given condition for achieving the maximum heat-flow rate.

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6

Frank, L. M. Pua, and (Frank) X. X. Zhu. "Integrated Heat Exchanger Network and Equipment Design Using Compact Heat Exchangers." Heat Transfer Engineering 23, no. 6 (November 2002): 18–35. http://dx.doi.org/10.1080/01457630290098691.

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7

Markowski, Mariusz, and Krzysztof Urbaniec. "Optimal cleaning schedule for heat exchangers in a heat exchanger network." Applied Thermal Engineering 25, no. 7 (May 2005): 1019–32. http://dx.doi.org/10.1016/j.applthermaleng.2004.06.025.

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8

Huda, Hairul, Renanto Handogo, Totok Ruki Biyanto, Wei Wu, and Vincentius Surya Kurnia Adi. "Oil Refinery Heat Exchanger Network Cleaning Scheduling Strategy with Unit Cleanability Consideration." ASEAN Journal of Chemical Engineering 20, no. 1 (June 29, 2020): 31. http://dx.doi.org/10.22146/ajche.51880.

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Heat exchanger networks (HENs) play an important role in the chemical industries. Unfortunately, fouling is inevitable in heat exchangers operation. Therefore, the optimal cleaning procedure is required to restore heat exchangers' performance periodically. A systematic cleaning scheduling strategy for the heat exchanger network in an oil refinery is proposed in this work. There are 11 operating heat exchangers in an oil refinery to be reviewed. Different cleaning decision scenarios based on the overall heat transfer coefficient are explored for optimal cleaning schedule performance. The daily number of exchangers available to be cleaned i.e., the unit cleanability, is investigated while minimizing the energy consumption and the additional heat requirement due to the offline heat exchanger under cleaning procedure. The HEN performance and the energy-saving from the cleaning procedures are benchmarked with the uncleaned HEN. The results indicate that the cleaning procedure significantly increases the HEN performance and simultaneously reduces the heat requirement if compared to the untreated HEN benchmark. The possible conflicting situation is discussed when some heat exchangers are waiting to be cleaned due to the unit cleanability restriction, which allows the overall heat transfer coefficient to be below the allowed limit. Therefore, nonconflicting cleaning scheduling is also addressed in this work by relaxing the unit cleanability limit. Furthermore, the optimal cleaning schedule is also suggested for user reference. In this work, the optimum cleaning schedule with minimum energy consumption and maximum energy saving could be achieved when cleaning decision limit is set at 40% decrease of overall heat transfer coefficient. In the contrast, the lowest number of cleaning procedures is associated with 90% decrease in the overall heat transfer coefficient as the cleaning decision limit.

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9

Dı´az, Gerardo, Mihir Sen, K. T. Yang, and Rodney L. McClain. "Adaptive Neurocontrol of Heat Exchangers." Journal of Heat Transfer 123, no. 3 (January 8, 2001): 556–62. http://dx.doi.org/10.1115/1.1370512.

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This paper investigates the use of adaptive artificial neural networks (ANNs) to control the exit air temperature of a compact heat exchanger. The controllers, based on an internal model control scheme, can be adapted on-line on the basis of different performance criteria. By numerical simulation a methodology by which the weights and biases of the neural network are modified according to these criteria was developed. An ANN controller for an air-water compact heat exchanger in an experimental facility is then implemented. The parameters of the neural net are modified using three criteria: minimization of target error, stabilization of the closed-loop performance of the controller, and minimization of a performance index that we have taken to be the energy consumption. It is shown that the neural network is able to control the air exit temperature in the heat exchanger. The neurocontroller is able to adapt to major structural changes in the system as well as to simultaneously minimize the amount of energy used.

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10

Brown, Christopher S., Nigel J. Cassidy, Stuart S. Egan, and Dan Griffiths. "Thermal and Economic Analysis of Heat Exchangers as Part of a Geothermal District Heating Scheme in the Cheshire Basin, UK." Energies 15, no. 6 (March 9, 2022): 1983. http://dx.doi.org/10.3390/en15061983.

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Heat exchangers are vital to any geothermal system looking to use direct heat supplied via a district heat network. Attention on geothermal schemes in the UK has been growing, with minimal attention on the performance of heat exchangers. In this study, different types of heat exchangers are analysed for the Cheshire Basin as a case study, specifically the Crewe area, to establish their effectiveness and optimal heat transfer area. The results indicate that counter-current flow heat exchangers have a higher effectiveness than co-current heat exchangers. Optimisation of the heat exchange area can produce total savings of £43.06 million and £71.5 million, over a 25-year lifetime, in comparison with a fossil-fuelled district heat network using geothermal fluid input temperatures of 67 °C and 86 °C, respectively.

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11

Trafczynski, Marian, Mariusz Markowski, Piotr Kisielewski, Krzysztof Urbaniec, and Jacek Wernik. "A Modeling Framework to Investigate the Influence of Fouling on the Dynamic Characteristics of PID-Controlled Heat Exchangers and Their Networks." Applied Sciences 9, no. 5 (February 26, 2019): 824. http://dx.doi.org/10.3390/app9050824.

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The present work is an extension of the authors’ previous research, where changes in the dynamic behavior of heat exchangers induced by fouling build-up were studied. In the present work, the authors used the previously elaborated and validated mathematical model of transient heat exchange with the influence of thermal resistance of fouling taken into account. The behavior of specific Heat Exchanger Networks (HENs) coupled with a Crude Distillation Unit together with their control loops is simulated using Simulink/MATLAB and the influence of fouling build-up on specific indices of quality of operation is investigated. According to the presented results, the higher the number of heat exchangers in the PID control loop and the greater the number of heat exchangers interacting in the network, the smaller the influence of fouling on the control quality indices, and in the extreme case, this influence may be negligible. This might be caused by the compensation of the negative effects of fouling build-up when the heat exchangers are interacting in the HEN. Nevertheless, potential adverse effects of fouling on HEN operation can be prevented by periodic adjustments of the optimal values of PID gains.

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12

Markowski, Mariusz, and Marian Trafczyński. "A Neural Network Assisted On-Line Cleaning of Heat Exchanger Network." Applied Mechanics and Materials 797 (November 2015): 192–201. http://dx.doi.org/10.4028/www.scientific.net/amm.797.192.

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On-line cleaning of heat exchangers operating in a heat exchanger network (HEN) is aimed at preventing unnecessary losses of energy that can be recovered in HEN. If time behaviour of fouling in each heat exchanger can be estimated on the basis of past experience, then the optimal schedule of cleaning interventions can be determined by maximizing the objective function expressing the economic value of avoidable reduction in the energy recovery [1]. The crucial assumption for the presented paper is that on-line measurements of the mass flow and inlet and outlet temperature are available for each process stream. That made possible to evaluate fouling-induced reduction in the recovered energy flow using neural network model of HEN based on the measurements. The neural network (NN) model of HEN was applied in diagnostics of deposits influence on heat recovery in HEN by taking into account the time behaviour of fouling approximated by NN. The application of a neural network to the evaluation of changes in the energy flow recovered in a HEN has been tested using a simulated heat exchanger network as a reference. The simulation of HEN (implemented in MATLAB software) was based on a dynamic HEN model employing heat exchanger decomposition into interconnected cells whose overall dynamic behaviour is described by an array of lumped-parameter models. Computational aspects of the approach outlined above were studied on the example of a HEN featuring 26 process streams and 31 heat exchangers, operating in a crude distillation unit of 440 t/h processing capacity. A diagnostics of deposits influence on heat recovery in HEN makes it possible to attain a saving of about 5% of recoverable energy with the annual value of about 0,86 million USD.

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13

Fyk, Mykhailo, Volodymyr Biletskyi, Ihor Ryshchenko, and Mohammed Abbood. "Improving the geometric topology of geothermal heat exchangers in oil bore-holes." E3S Web of Conferences 123 (2019): 01023. http://dx.doi.org/10.1051/e3sconf/201912301023.

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A review has been conducted of key trends in the development of geometric topology of geothermal heat exchangers. Authors proposed approaches to improving the designs and network structures for heat-transfer media circulation in the bottom-hole space of oil-and-gas reservoirs. Four geometric topologies of geothermal heat exchangers have been analysed: І – ІІ – rectilinear vertical smooth and finned pipelines; ІІІ – IV – a cluster in the form of a set of smooth and finned single-pipe elements, representing a figure of “squirrel wheel” or “meridian sphere” type. It is shown that the most effective technical solution, which ensures the increase in the coefficient of performance (COP) of bore-hole geothermal systems is finning the heat exchanging pipes. For the heat exchangers of І – ІІ type, the calculated increase in COP in comparison with smooth pipes is 40%, and for ІІІ – IV type – 95%. The key parameters influencing the COP of a geothermal heat exchanger are: the radius of fluids draining out during the heat exchange process, the radius of pipelines with circulating heat-transfer medium, the diameter of a cluster heat exchanger, the heat exchange area, the parameters of rocks thermal resistance in the bottom-hole zone of heat-receiving.

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14

Gilfanov, K. K., and R. A. Shakirov. "Intellectual modeling of surface heat-exchange enhancer based on artificial neural networks." E3S Web of Conferences 124 (2019): 03007. http://dx.doi.org/10.1051/e3sconf/201912403007.

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The results of neural network modeling of average heat transfer in the channels of exchangers with surface enhancer of different shapes are presented. Artificial neural networks are trained using experimental data, which covers more than ten sources. The possibility and prospects of building artificial neural networks for modeling the characteristics of heat exchange surfaces are shown.

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15

Gvozdenac, Dusan. "Heat exchanger operating point determination." Thermal Science 13, no. 4 (2009): 151–64. http://dx.doi.org/10.2298/tsci0904151g.

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This paper indicates 21 possible tasks for the calculation of heat exchangers and specifies in particular the procedure for determining heat exchanger operating point. Features of heat exchanger energy micro-balance are contained in its mathematical model, and features of its macro-balance hold in relations for heat flow rate. Operating point of heat exchanger is defined by satisfying micro and macro balances. The paper presents basic relations for determining operating points for some types of tasks and algorithms of certain procedures. A special case in which two, one or none non-trivial solutions appear within two of 21 tasks is analyzed and discussed separately. Presented procedures are very suitable for the preparation of own software for the calculation of operating parameters of any heat exchanger and analysis of heat exchangers network.

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16

Chen, Jiaxing, Guomin Cui, Mei Cao, Heri Kayange, and Jian Li. "Heat Exchanger Network Optimization Based on the Participatory Evolution Strategy for Streams." Energies 14, no. 24 (December 13, 2021): 8392. http://dx.doi.org/10.3390/en14248392.

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The non-structural model of a heat exchanger network randomly selects a position of a node on hot and cold streams to generate a heat exchanger and an existing heat exchanger to participate in the evolution. Despite the model being more random and flexible, this selection method cannot easily find a good solution. In addition, the heat exchangers participating in the evolution might not be involved in all streams in each evolutionary process. A stream that does not participate in the evolution will have no significance to the current iteration. Therefore, many iterations are required to make each stream participate in the evolution, which limits the evolution efficiency of the optimization algorithm. In view of this shortcoming, this study proposes a participatory evolutionary strategy for streams based on hot streams. The proposed strategy reorders the existing heat exchangers on hot and cold streams and takes the corresponding measures to ensure that a heat exchanger is selected for each stream to participate in the evolution in every cycle. The proposed participatory evolutionary strategy for streams improves the global optimal solution for designs based on non-structural models. The effectiveness of the proposed strategy is demonstrated in two cases.

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17

Jiang, Bin, Xiao Ling Yang, and Lu Hong Zhang. "Heat Transfer Prediction for Helical Baffle Heat Exchangers with Experimental Data by Radial Basis Function Neural Networks." Advanced Materials Research 452-453 (January 2012): 1441–45. http://dx.doi.org/10.4028/www.scientific.net/amr.452-453.1441.

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In this paper an artificial neural network (ANN) is used to correlate experimentally determined heat transfer rate of non-continuous helical baffle heat exchangers. First the heat exchangers with three helical angles were experimentally investigated under different inlet volumetric flow rate and temperature. The commonly implemented radial-basis function (RBF) neural network is applied to develop a prediction model based on the limited experimental data. Compared with correlations, the RBF network exhibits superiority in accuracy. The satisfactory results suggest the RBF network might be used to predict the thermal performance of shell-and-tube heat exchangers with helical baffles.

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18

Jegla, Zdeněk, and Vít Freisleben. "Practical Energy Retrofit of Heat Exchanger Network Not Containing Utility Path." Energies 13, no. 11 (May 28, 2020): 2711. http://dx.doi.org/10.3390/en13112711.

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The paper presents a method developed for the energy retrofit of specific Heat Exchanger Networks not containing Utility Paths. This useful and highly practically oriented method involves a systematic approach to obtaining the most efficient minimal modification topology of a Heat Exchanger Network, which brings the greatest benefits in terms of energy savings of the modified process. In principle, it is focused on finding the most suitable location for a new heat exchanger insertion to create the most efficient Utility Path. The next step of the developed retrofit method is the detailed design of the newly integrated heat exchanger using commercial software in combination with several heuristic rules regarding the cost-free investment and maintenance cost minimization of a new heat exchanger and considering heat transfer enhancement within the available exchanger type, space, and fluids pressure drop constraints. The detail design stage of the method also includes observation and reassessment of the performance and operational parameters of the existing heat exchangers. Then, the developed method is applied to the case of the Heat Exchanger Network retrofit in the process of the hydrogenation of oil.

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19

Nielsen, Jørgen Bremnes, and Eilif Pedersen. "On the modelling of heat exchangers and heat exchanger network dynamics using bond graphs." Mathematical and Computer Modelling of Dynamical Systems 24, no. 6 (October 15, 2018): 626–42. http://dx.doi.org/10.1080/13873954.2018.1533566.

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20

Sun, Kheen Nam, Sharifah Rafidah Wan Alwi, and Zainuddin Abdul Manan. "Heat exchanger network cost optimization considering multiple utilities and different types of heat exchangers." Computers & Chemical Engineering 49 (February 2013): 194–204. http://dx.doi.org/10.1016/j.compchemeng.2012.10.017.

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21

Lazzaretto, A., and F. Segato. "Thermodynamic Optimization of the HAT Cycle Plant Structure—Part II: Structure of the Heat Exchanger Network." Journal of Engineering for Gas Turbines and Power 123, no. 1 (January 23, 2000): 8–16. http://dx.doi.org/10.1115/1.1339000.

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In Part I of the paper a thermodynamic optimization methodology was presented for the “basic” configuration of a humid air turbine cycle plant in which the heat exchange section is viewed as a black-box separated from the rest of the plant (basic components), having a fixed structure. The results of the optimization apply to all the heat exchanger networks that fulfill the optimal boundary conditions between the black-box and the rest of the plant. The aim of this part is to define these heat exchanger networks using a combination of Pinch Technology and Second Law insights. The possibility of a further reduction in the number of heat exchangers is then investigated in order to achieve the best compromise between high performances and structural simplicity.

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Lazzaretto, A., and F. Segato. "Thermodynamic Optimization of the HAT Cycle Plant Structure—Part I: Optimization of the “Basic Plant Configuration”." Journal of Engineering for Gas Turbines and Power 123, no. 1 (January 23, 2000): 1–7. http://dx.doi.org/10.1115/1.1338999.

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A method for the thermodynamic optimization of the humid air turbine cycle plant structure is presented here. The method is based on the optimization of a “basic configuration of the plant” including “basic components” (compressor, turbine, combustion chamber, regenerator, and saturator), always present and connected in the same way in the plant structure and a heat exchange section which is viewed as a “black-box” where the heat transfer between hot and cold thermal flows occurs regardless of how many heat exchangers there are and of how they are interconnected. The optimal boundary conditions between the basic components and black-box are determined by calculating the conditions of maximum heat transfer in the black-box independently of the structure of the heat exchanger network. This is done by defining optimal composite curves in a Fortran routine at each step in the main optimization procedure. Once the structure of the heat exchanger networks that fulfill the optimal boundary conditions have been found, the optimal structure of the whole plant is obtained (see Section 2). The method is useful in a general sense as it can be applied to highly integrated energy systems in which it is difficult to define the optimal structure of the heat exchanger network in advance.

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23

Carvalho, Carolina, Esdras Carvalho, and Mauro Ravagnani. "Combined neural networks and predictive control for heat exchanger networks operation." Chemical Industry and Chemical Engineering Quarterly 26, no. 2 (2020): 125–34. http://dx.doi.org/10.2298/ciceq190530031c.

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Optimal operation of integrated heat exchangers is a challenging task in the field of process control due to system nonlinearities, disturbances and adequate model identification. This paper describes the design of an advanced neural network predictive control (NNPC) applied to a heat exchanger network. A case study with two hot and one cold streams, through three counter-current heat exchangers is used to test the proposed strategy. A lumped dynamic model is built based on the concept of multi-cells topology (mixed tanks), where the hot and cold cells are connected by a wall element throughout the heat exchanger length. Each cell is assumed perfectly mixed and all physical properties are constant. A distributed behavior is achieved by increasing the number of cells. The main assumptions of the lumped model are constant temperature in each cell, heat exchanger volume and area equally distributed between cells and negligible heat loss to the environment. The predictive controller relies on a neural-based model of the plant that is used to identify the system and to predict future performance over a predefined horizon. Results were compared to a traditional controller, and the control performance was improved when compared to the Ziegler-Nichols tuning method.

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24

Fumuassuca, Diana S., Marcilio Dos Santos, and Antonio A. Chivanga Barros. "Pinch Analysis Applied to Atmospheric Distillation Column." Angolan Mineral, Oil & Gas Journal 1, no. 1 (May 6, 2020): 11–15. http://dx.doi.org/10.47444/amogj.v1i1.6.

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To increase the efficiency of industrial processes, mainly in petroleum refineries, the strategies to energy optimization are being developed. Thus, there is a need to know the energy consumption analysis in term of loss level and to define the procedure to recovery that. The analyses involve the flow rate study, based on energy balances that define the best strategy to use the energy, with the installation of heat exchanger networks. With the use of this procedure, we can reduce the operational costs, associated with a reduction of the level energy consumption. The study developed here was related to refinery atmospheric distillation column, using pinch technology, based on energy conservation law. The pre-flash, atmospheric distillation column and heat exchangers networks were evaluated in this study. The dates used in this study were collected from Angolan refinery, during 30 days and the results were used to mass and energy balances. Previously, the flow sheet process and established the relations between the operational parameters in industrial equipment were evaluated. The results from energy balances were used to integration study, supported by the pinch analysis using spreadsheet software, and the dates showed as composite, great composite and cascade curves. For this, were used the heat exchanger battery based on pinch analysis, to make the new networks of energy integration. After the assessment of each network with 4 to 12 heat exchangers, it was optimized to know that one with better energy consumption. The new network proposed is evaluated in term of reduction of energy consumption, minor number of heat exchangers and networks optimization. As a result of this methodology, we can see the reduction of energy consumption of 785,4 KW (utility) and 1277,1 KW (cold), respectively. On other hand, the optimization strategy adopted here allowed increase the temperature to 301ºC.

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Mathew, Shadrack Uzoma, and Lebari Aban Tamzor. "Heat Exchanger Process Optimization in A Typical Brewery Plant." European Journal of Engineering Research and Science 5, no. 1 (January 16, 2020): 76–81. http://dx.doi.org/10.24018/ejers.2020.5.1.1598.

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The research attempts to improve upon the performance efficiency of the heat exchanger network system of Pabod Brewery, Port Harcourt, Rivers State, Nigeria. It swaps the heat system of the plant by the use of Pinch Technology to recover waste heat and integrating the recovered energy for process application. The application software is Microsoft Excel and Problem Table Method was employed in the numerical analysis of data. The gross energy expenditure by the plant is 10.44MW at production capacity of 400,000 liters of beer per day. On quantitative aggregate 6.157MW goes for heating and 4.267MW for cooling. A temperature pinch or minimum approach temperature (ΔTmin)of 100C was used in the pinch analysis of the heat exchangers performance. The research findings confirmed minimum heating utility of 5.04MW and cooling utility of 3.09MW. with energy upturn of 1.08MW and 1.23MW for the hot and cold flows respectively. This correlates to energy conservation of 18% for hot utility and 21% for the cold utility. The hot stream pinch temperature is 710C while that of the cold stream is 610C. Heat exchangers network configuration design were performed above and below the pinch The network designs were produced and integrated to produce improved heat exchanger network system for the Brewery plant.

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Mathew, Shadrack Uzoma, and Lebari Aban Tamzor. "Heat Exchanger Process Optimization in A Typical Brewery Plant." European Journal of Engineering and Technology Research 5, no. 1 (January 16, 2020): 76–81. http://dx.doi.org/10.24018/ejeng.2020.5.1.1598.

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The research attempts to improve upon the performance efficiency of the heat exchanger network system of Pabod Brewery, Port Harcourt, Rivers State, Nigeria. It swaps the heat system of the plant by the use of Pinch Technology to recover waste heat and integrating the recovered energy for process application. The application software is Microsoft Excel and Problem Table Method was employed in the numerical analysis of data. The gross energy expenditure by the plant is 10.44MW at production capacity of 400,000 liters of beer per day. On quantitative aggregate 6.157MW goes for heating and 4.267MW for cooling. A temperature pinch or minimum approach temperature (?Tmin)of 100C was used in the pinch analysis of the heat exchangers performance. The research findings confirmed minimum heating utility of 5.04MW and cooling utility of 3.09MW. with energy upturn of 1.08MW and 1.23MW for the hot and cold flows respectively. This correlates to energy conservation of 18% for hot utility and 21% for the cold utility. The hot stream pinch temperature is 710C while that of the cold stream is 610C. Heat exchangers network configuration design were performed above and below the pinch The network designs were produced and integrated to produce improved heat exchanger network system for the Brewery plant.

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Meng, Yan Mei, Hai Feng Pang, Yan Jiang, Quan Zhou, Ting Ting Zheng, and Qiao Ling Jin. "Analysis of Heat Exchanger Performance Forecast Based on the BP Neural Network." Advanced Materials Research 139-141 (October 2010): 1697–701. http://dx.doi.org/10.4028/www.scientific.net/amr.139-141.1697.

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This paper uses the BP neural network algorithm to predict the performance of heat exchangers, sets up a applied structure of the BP neural network and expounds the realization of predicted algorithm, including the determination of network structure, the learning rate, the network performance evaluation, the training and test aggregate, the network target errors and the network training times and so on, which is the simulation of predicting the performance of a heat exchanger with pipes buried underground in a ground source heat pump system. The results of prediction show that the relative errors of the heat exchanger performance prediction are mostly within 5.4%, and the neural network prediction results agree well with the experimental results, which have better generalization ability. This research method for underground heat exchanger can provide basis for optimizing the parameters, so it has certain practical significance and social value.

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Xu, Yue, Heri Ambonisye Kayange, and Guomin Cui. "A Nodes-Based Non-Structural Model Considering a Series Structure for Heat Exchanger Network Synthesis." Processes 8, no. 6 (June 15, 2020): 695. http://dx.doi.org/10.3390/pr8060695.

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The aim of heat exchanger network synthesis is to design a cost-effective network configuration with the maximum energy recovery. Therefore, a nodes-based non-structural model considering a series structure (NNM) is proposed. The proposed model utilizes a simple principle based on setting the nodes on streams such that to achieve optimization of a heat exchanger network synthesis (HENS) problem. The proposed model uses several nodes to quantify the possible positions of heat exchangers so that the matching between hot and cold streams is random and free. Besides the stream splits, heat exchangers with series structures are introduced in the proposed model. The heuristic algorithm used to solve NNM model is a random walk algorithm with compulsive evolution. The proposed model is used to solve four scale cases of a HENS problem, the results show that the costs obtained by NNM model can be respectively lower 3226 $/a(Case 1), 11,056 $/a(Case 2), 2463 $/a(Case 3), 527 $/a(Case 4) than the best costs listed in literature.

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29

Morton, W. "Optimization of a heat exchanger network superstructure using nonlinear programming." Proceedings of the Institution of Mechanical Engineers, Part E: Journal of Process Mechanical Engineering 216, no. 2 (May 1, 2002): 89–104. http://dx.doi.org/10.1243/095440802760075797.

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A heat exchanger network design for a particular set of hot and cold stream duties requires multiple stream splits for minimum energy use. A modern NLP solver, FilterSQP, is applied to minimize a total cost function that takes account of capital and energy costs. The best solution contains fewer exchangers than the initial network. There are multiple local optima at various cost levels. They contain different subsets of exchangers of the initial design, which constitutes a partial superstructure for the problem. Several optimization alternatives are examined: for the model formulation, leading to problems with different optimum costs, for the way the objective is written, which affects the formal degree of nonlinearity in the equations or objective, and for the way the solver operates. For each combination of options, tests were run using widely different initial values for the Trust Region size, a parameter in the solver. FilterSQP solved the network with impressive reliability and efficiency from several starting guesses, some of which were highly arbitrary. From even the most unpromising initial guesses, the solver converged to a local optimum in nearly all cases.

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30

Jiang, Ning, Jacob David Shelley, and Robin Smith. "New models for conventional and heat exchangers enhanced with tube inserts for heat exchanger network retrofit." Applied Thermal Engineering 70, no. 1 (September 2014): 944–56. http://dx.doi.org/10.1016/j.applthermaleng.2014.06.015.

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Zitte, B., B. Hamroun, F. Couenne, and I. Pitault. "Extremum-Seeking Based Distributed Optimization of Heat Exchangers Network." IFAC-PapersOnLine 51, no. 23 (2018): 331–36. http://dx.doi.org/10.1016/j.ifacol.2018.12.057.

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32

Nair, Sajitha K., Melvin Soon, and I. A. Karimi. "Locating exchangers in an EIP-wide heat integration network." Computers & Chemical Engineering 108 (January 2018): 57–73. http://dx.doi.org/10.1016/j.compchemeng.2017.08.004.

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33

Thuy, Ngo Thi Phuong, Rajashekhar Pendyala, and Narahari Marneni. "Heat Exchanger Network Optimization Using Differential Evolution with Stream Splitting." Applied Mechanics and Materials 625 (September 2014): 373–77. http://dx.doi.org/10.4028/www.scientific.net/amm.625.373.

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Reduction in energy consumption is an important task in process industry. The basic idea of heat exchanger network (HEN) is using cold streams to cool hot streams and hot streams to heat cold streams. Hence, synthesis and optimization of HEN is a main tool for improving heat recovery. This article introduces a new strategy for HEN optimization using differential evolution algorithm. The proposed method considers splitting stream at the pinch point, to minimize the total cost of the network. Primarily, the minimum approach temperature value is determined through super-targeting. Then, differential evolution is employed to specify the heat load of heat exchangers and splitting streams. The HEN structure obtained in this work has better economics and illustrates the better performance by this approach.

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34

Vasičkaninová, Anna, Monika Bakošová, and Alajos Mészáros. "Control of heat exchangers in series using neural network predictive controllers." Acta Chimica Slovaca 13, no. 1 (April 1, 2020): 41–48. http://dx.doi.org/10.2478/acs-2020-0007.

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AbstractThe paper reveals three applications of neural network predictive control (NNPC) to a system of four heat exchangers (HEs) in series with counterflow configuration to save energy expressed by cooling water in the system of HEs cooling the distillation product. Neural networks (NNs) are used at first in conventional NNPC and subsequently, neural network predictive controllers (NNPCLs) are employed as a master controller in a cascade control, and as a feedback controller in the control system with disturbance measurement. Neural-network-predictive-control-based (NNPC-based) feedback control systems are compared with PI controller based feedback control loop. Series of simulation experiments were done and the results showed that using NNPC-based cascade control reduced cooling water consumption. This control system also significantly reduced the settling time and overshoots in the control responses and provided the best assessed integral quality criteria compared to other control systems. NNPC-based cascade control can also be interesting for industrial use. Generally, simulation results proved that NNPC-based control systems are promising means for the improvement of HEs control and achievement of energy saving.

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35

BABIDORICH, M. I., P. S. PENKOVA, and O. A. REUTOVA. "OPTIMAL REALIZATION HEAT EXCHANGE IN THE PROCESSES OF GAS FRACTIONATION." Applied Mathematics and Fundamental Informatics 6, no. 4 (2019): 039–45. http://dx.doi.org/10.25206/2311-4908-2019-6-4-39-45.

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He article presents a study of gas fractionating plant, which is associated with the problem of high energy consumption for heating and cooling of technological flows. To solve this problem, a method of heat utilization of isopentane fraction streams and gas gasoline for heating cold streams was proposed. This process of heat exchange was integrated into the existing network of heat exchangers and analyzed using the pinch analysis method. The plant model developed at Aspen HYSYS using data from real plants was exported to Aspen Energy Analyzer. Analysis of the heat exchange network showed that the consumption of hot and cold energy can be reduced by 6.4% and 4.4%, respectively.

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36

Natig Abbasov, Natig Abbasov, and Ziyaddin Ziyaddinli Ziyaddin Ziyaddinli. "OPTIMAL DESIGN OF HEAT EXCHANGER NETWORK IN OIL REFINERIES." ETM - Equipment, Technologies, Materials 06, no. 02 (April 4, 2021): 86–90. http://dx.doi.org/10.36962/etm0602202186.

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The performance of the heat exchanger network (HEN) in a plant is an important aspect of energy conservation. “Pinch” technology and mathematical programming techniques offer an effective and practical method for designing the HEN for new and retrofit projects. The fluid catalytic cracking (FCC) is a dominant process in oil refineries and there has been a sustained effort to improve the efficiency and yield of the unit over the years. HEN optimal design in FCC process is an essential element in reducing the cost and improving the process as a whole. The objective of this work is to introduce a systematic procedure for designing optimal and flexible FCC-HEN that incorporates variations in feed flow rates and specs and on same time considers different schedules imposed on the process. Keywords: heat exchangers, fluid catalytic cracking, design of network, oil refinery, heat recovery systems

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37

Jeon, Jun-Seo, Seung-Rae Lee, Min-Jun Kim, and Seok Yoon. "Suggestion of a Scale Factor to Design Spiral-Coil-Type Horizontal Ground Heat Exchangers." Energies 11, no. 10 (October 12, 2018): 2736. http://dx.doi.org/10.3390/en11102736.

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Spiral-coil-type horizontal ground heat exchangers (GHEs) have been increasingly used in ground source heat pump (GSHP) systems due to their higher heat transfer performance. Many attempts have been made to investigate the heat transfer mechanism and establish design methods for the spiral-coil-type ground heat exchangers. Nevertheless, a universal design method for horizontal GHEs has not been reported due to its complexity. In contrast to the spiral-coil-type horizontal GHEs, straight-line-type horizontal GHEs have been widely adopted since they are easy to design for use in industry. In this study, a scale factor model, which could be used to design the coil-type exchanger based on the design length of a straight-line-type heat exchanger, was presented. The ratio of the mean thermal transfer energy between the straight-line-type and spiral-coil-type heat exchangers was numerically investigated by considering weather condition, configuration of GHE, and thermal properties of the ground. Using the numerical results for a total of 108 cases, artificial neural network and linear regression methods were employed for the model development. The proposed model of the scale factor may provide an alternative way to design the spiral-coil-type horizontal GHEs.

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38

Karimi, Habib, Hossein Ahmadi Danesh Ashtiani, and Cyrus Aghanajafi. "Study of mixed materials heat exchanger using optimization techniques." Journal of Engineering, Design and Technology 17, no. 2 (April 1, 2019): 414–33. http://dx.doi.org/10.1108/jedt-09-2018-0142.

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Purpose This paper aims to examine total annual cost from economic view mixed materials heat exchangers based on three optimization algorithms. This study compares the use of three optimization algorithms in the design of economic optimization shell and tube mixed material heat exchangers. Design/methodology/approach A shell and tube mixed materials heat exchanger optimization design approach is expanded based on the total annual cost measured by dividing the costs of the heat exchanger to area of surface and power consumption. In this study, optimization and minimization of the total annual cost is considered as the objective function. There are three types of exchangers: cheap, expensive and mixed. Mixed materials are used in corrosive flows in the heat exchanger network. The present study explores the use of three optimization techniques, namely, hybrid genetic-particle swarm optimization, shuffled frog leaping algorithm techniques and ant colony optimization. Findings There are three parameters as decision variables such as tube outer diameter, shell diameter and central baffle spacing considered for optimization. Results have been compared with the findings of previous studies to demonstrate the accuracy of algorithms. Originality/value The present study explores the use of three optimization techniques, namely, hybrid genetic-particle swarm optimization, shuffled frog leaping algorithm techniques and ant colony optimization. This study has demonstrated successful application of each technique for the optimal design of a mixed material shell and tube heat exchanger from the economic view point.

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39

Bala Bhaskara Rao, J., V. Ramachandra Raju, and BBVL Deepak. "A smart prediction tool for estimating heat transfer and overall pressure drop from shell-and-tube heat exchanger." Proceedings of the Institution of Mechanical Engineers, Part E: Journal of Process Mechanical Engineering 231, no. 5 (June 24, 2016): 1053–62. http://dx.doi.org/10.1177/0954408916656388.

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Almost all thermal/chemical industries are equipped with heat exchangers in order to enhance the thermal efficiency. The performance of a shell and tube heat exchanger depends significantly on the design parameters like the tube cross-sectional area, tube orientation, baffle cut, etc. However, there are no specific relationships among these parameters to obtain an optimal design, such that the heat transfer rate is maximized and the pressure drop is minimized. Therefore, experimental and numerical simulations are carried out for a heat exchanger at various process parameters. Heat exchanger considered in this investigation is a single shell-multiple pass type device. For the performed experimental datasets, a generalized regression neural network is applied to generate a relation among the input and output process parameters.

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40

Golosnoy, I. O., A. Cockburn, and T. W. Clyne. "Optimisation of Metallic Fibre Network Materials for Compact Heat Exchangers." Advanced Engineering Materials 10, no. 3 (March 2008): 210–18. http://dx.doi.org/10.1002/adem.200800021.

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41

Englart, Sebastian, Andrzej Jedlikowski, Wojciech Cepiński, and Marek Badura. "Renewable energy sources for gas preheating." E3S Web of Conferences 116 (2019): 00019. http://dx.doi.org/10.1051/e3sconf/201911600019.

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To ensure proper gas supply parameters, to the polish natural gas distribution network, which includes about 900 pressure reduction stations (PRS), requires high energy consumption for gas heating, that amounts to approx. 700 TJ/year. This value can be significantly reduced by using renewable energy sources (e.g. ground heat exchangers, heat pumps) in polish gas preheating PRS. This paper presents the analysis of some applications for gas preheating by using gas absorption heat pump and combination of heat pump and ground heat exchanger. The results confirm a noticeable heat energy savings at the PRS by 44%.

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42

Pacheco-Vega, Arturo, Gerardo Dı´az, Mihir Sen, K. T. Yang, and Rodney L. McClain. "Heat Rate Predictions in Humid Air-Water Heat Exchangers Using Correlations and Neural Networks." Journal of Heat Transfer 123, no. 2 (October 3, 2000): 348–54. http://dx.doi.org/10.1115/1.1351167.

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We consider the flow of humid air over fin-tube multi-row multi-column compact heat exchangers with possible condensation. Previously published experimental data are used to show that a regression analysis for the best-fit correlation of a prescribed form does not provide an unique answer, and that there are small but significant differences between the predictions of the different correlations thus obtained. It is also shown that it is more accurate to predict the heat rate directly rather than through intermediate quantities like the j-factors. The artificial neural network technique is offered as an alternative technique. It is trained with experimental values of the humid-air flow rates, dry-bulb and wet-bulb inlet temperatures, fin spacing, and heat transfer rates. The trained network is then used to make predictions of the heat transfer. Comparison of the results demonstrates that the neural network is more accurate than conventional correlations.

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43

Bărbulescu, Alina, and Lucica Barbeş. "Modeling the outlet temperature in heat exchangers: Case study." Thermal Science, no. 00 (2019): 449. http://dx.doi.org/10.2298/tsci190913449b.

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This article presents the results of the study of the heat transfer in a heat exchanger where the working fluid is the crude oil prepared for desalination, and the thermic agent is the recirculating heavy gasoline fraction. Firstly, the Reynolds numbers have been computed using the temperatures and flow rates of the fluids as input variables. Then, General Regression Neural Network and Multilayer Perceptron (MLP) were used for the outlet temperatures estimation using the inlet temperatures and the Reynolds numbers as input variables. The best models on the training dataset were obtained utilizing a MLP with one hidden layer, while the best performance on the validation dataset was obtained using a MLP network with two hidden layers

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44

Yakovleva, O., O. Ostapenko, and V. Trandafilov. "EN Energy efficiency projects deployment for Ukrainian industry. Efficiency assessment method for energy exchange and the ratio of temperature change in heat exchangers." Refrigeration Engineering and Technology 56, no. 1-2 (July 4, 2020): 54–59. http://dx.doi.org/10.15673/ret.v56i1-2.1829.

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Energy efficiency projects deployment for Ukraine is one of the challenging task today. Ukrainian industry faces very complex environment for project development as well as its deployment within organization nowadays. UA Policy struggle to keep place on the European market to have possibility not only be a part of global policy but to go forward and to bring benefits for macro and micro economy. Fresh breath by integration energy systems within project management into business model of organization let to move closer to hold under control energy efficiency projects realization and avoid financial risks. Environmental policy and energy policy play crucial role for Ukrainian transformation into European player. Presented proactive plan provides possibilities to deliver the intended economic and environmental benefits of the Ukrainian energy labelling and ecological design directives. These directives are in use or are under development process by increasing the rates of compliance with their energy efficiency requirements. To start from the energy efficiency development process investigation in order to have possibilities to make corrections on the stage of modeling and design can bring benefits and reduce costs for end users. To evaluate the efficiency of heat exchangers, there are over 40 different private integral energy efficiency criteria. Such a number makes the estimation of heat exchangers not always objective and sufficiently definite, which does not allow to algorithmize the task of determining the efficiency of heat exchangers. On the foundation of the system element representation for the heat exchange network, the concepts of energy potential and energy efficiency of energy exchange are proposed. The obtained equations allow us to determine the efficiency of energy exchange not only for an element of the heat exchange network, but also for a complex system as a whole with a minimum of information about the system

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45

Kamel, Dina Ahmed, Mamdouh Ayad Gadalla, and Fatma Hanafy Ashour. "A New Graphical Technique for Energy Efficient Design of Heat Recovery System in Chemical/Refining Industries." International Journal of Recent Contributions from Engineering, Science & IT (iJES) 4, no. 4 (December 30, 2016): 33. http://dx.doi.org/10.3991/ijes.v4i4.6543.

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Chemical processes are energy intensive industries; the majority of energy consumed in industrial processes is mainly used for heating and cooling requirements. This results in increasing the interest in obtaining the optimum design of the heat exchanger networks to reduce the energy consumption and face the growing energy crises. Most of the published literature over the last fifty years promotes the process integration technology as a main part of the process system engineering science. Graphical Pinch Analysis method normally includes two key steps, firstly obtaining the energy targets which include the minimum energy required for the HEN design, then designing the heat exchanger network (HEN). This paper introduces a new graphical approach for the design of new heat exchanger networks (HENs) based on pinch analysis rules. The HEN is represented on a simple graph, where the cold stream temperatures are plotted on the X-axis while the driving forces for each exchanger are plotted on the Y-axis. This graphical technique can describe the energy analysis problems in term of temperature driving force inside the heat exchanger, which is an important factor in the design process as the differences in these driving forces are involved in calculating the area of heat exchangers, and consequently affecting the cost.

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46

Corbett, Daniel C., Wesley B. Fabyan, Bagrat Grigoryan, Colleen E. O’Connor, Fredrik Johansson, Ivan Batalov, Mary C. Regier, Cole A. DeForest, Jordan S. Miller, and Kelly R. Stevens. "Thermofluidic heat exchangers for actuation of transcription in artificial tissues." Science Advances 6, no. 40 (September 2020): eabb9062. http://dx.doi.org/10.1126/sciadv.abb9062.

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Spatial patterns of gene expression in living organisms orchestrate cell decisions in development, homeostasis, and disease. However, most methods for reconstructing gene patterning in 3D cell culture and artificial tissues are restricted by patterning depth and scale. We introduce a depth- and scale-flexible method to direct volumetric gene expression patterning in 3D artificial tissues, which we call “heat exchangers for actuation of transcription” (HEAT). This approach leverages fluid-based heat transfer from printed networks in the tissues to activate heat-inducible transgenes expressed by embedded cells. We show that gene expression patterning can be tuned both spatially and dynamically by varying channel network architecture, fluid temperature, fluid flow direction, and stimulation timing in a user-defined manner and maintained in vivo. We apply this approach to activate the 3D positional expression of Wnt ligands and Wnt/β-catenin pathway regulators, which are major regulators of development, homeostasis, regeneration, and cancer throughout the animal kingdom.

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47

Wang, Peng, Xingqi Luo, Senlin Chen, Qingsen Cai, and Jinling Lu. "Energy Saving Application of Variable Speed Auxiliary Pump Plus Hydro Turbine in Circulating Cooling Water System." Journal of Physics: Conference Series 2029, no. 1 (September 1, 2021): 012070. http://dx.doi.org/10.1088/1742-6596/2029/1/012070.

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Abstract The circulating cooling water system (CCWS) is a common industrial auxiliary system, and water pumps need to consume much energy to transport cooling water to distributed heat exchangers. Previous studies show that a pump network configuration with constant speed auxiliary pump plus hydro turbine (CSAP-T) plays a significant role in energy conservation. However, given the fluctuations in the production load and cooling water supply temperature, the flow demand of heat exchangers for cooling water varies. Under different working conditions, the CSAP-T scheme cannot supply the minimum cooling water flow required by all heat exchangers at the same time, thereby wasting energy. Therefore, this paper proposes a new fluid machinery network configuration called variable speed auxiliary pump plus hydro turbine (VSAP-T) and establishes a mathematical model of the total output power of the fluid machinery network in CCWS to minimize network energy consumption. To illustrate the effectiveness of the VSAP-T scheme, a real system is used as the research object, and both CSAP-T and VSAP-T schemes are used to optimize the system. When the working conditions are changed, the total output power of the system fluid machinery network can be conserved by 30% to 50%.

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48

Santhosh shekar, M., P. Mohan Krishna, and M. Venkatesan. "Artificial Neural Network based Prediction of Pressure Drop in Heat Exchangers." Indian Journal of Science and Technology 8, S9 (May 11, 2015): 87. http://dx.doi.org/10.17485/ijst/2015/v8is9/65549.

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49

Hafizan, Ainur Munirah, Jiří Jaromír Klemeš, Sharifah Rafidah Wan Alwi, Zainuddin Abdul Manan, and Mohd Kamaruddin Abd Hamid. "Temperature Disturbance Management in a Heat Exchanger Network for Maximum Energy Recovery Considering Economic Analysis." Energies 12, no. 4 (February 13, 2019): 594. http://dx.doi.org/10.3390/en12040594.

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The design of heat exchanger networks (HEN) in the process industry has largely focused on minimisation of operating and capital costs using techniques such as pinch analysis or mathematical modelling. Aspects of operability and flexibility, including issues of disturbances affecting downstream processes during the operation of highly integrated HEN, still need development. This work presents a methodology to manage temperature disturbances in a HEN design to achieve maximum heat recovery, considering the impact of supply temperature fluctuations on utility consumption, heat exchanger sizing, bypass placement and economic performance. Key observations have been made and new heuristics are proposed to guide heat exchanger sizing to consider disturbances and bypass placement for cases above and below the HEN pinch point. Application of the methodology on two case studies shows that the impact of supply temperature fluctuations on downstream heat exchangers can be reduced through instant propagation of the disturbances to heaters or coolers. Where possible, the disturbances have been capitalised upon for additional heat recovery using the pinch analysis plus-minus principle as a guide. Results of the case study show that the HEN with maximum HE area yields economic savings of up to 15% per year relative to the HEN with a nominal HE area.

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50

Seryogina, Yu S., T. V. Shchukina, and Mohammed E. Abuaiash. "To the Issue of Choosing a Wastewater-Freon Heat Exchanger for a Vapor Compression Pump." Ecology and Industry of Russia 22, no. 8 (August 1, 2018): 4–7. http://dx.doi.org/10.18412/1816-0395-2018-8-4-7.

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A high level of energy-efficient operation of structures can be achieved through automated life-support systems using secondary energy resources. Analysis of thermal emissions in residential buildings allows us to conclude that the most promising for this purpose are wastewater. The process of utilizing the heat of the used water resources entering the sewerage network can be carried out in two types of evaporative heat exchangers: surface and submerged.The increased area and increased heat transfer efficiency create the conditions for the preferable choice of a submersible type storage wastewater-freon heat exchanger. The design of the case of devices of this type allows to obtain a model range by the step change in its diameter. The calculations carried out for the case diameters of 300, 400, 500 mm have shown that at various water flows the best heat exchange parameters are achieved at a diameter of 300 mm, both under conditions of forced and natural convection.

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