Multiple Heat Sources Research Articles

Experimental study on Start-Up and heat transfer characteristics in loop heat pipes with dual heat sources for battery thermal management system

Electric vehicles represent a breakthrough in sustainable transportation, significantly diminishing global emissions. The efficacy of lithium-ion batteries is significantly influenced by the operating temperature, with elevated temperatures potentially resulting in thermal runaway. A proficient battery thermal management system (TMS) must resolve this concern and uphold safe temperatures. Loop heat pipes (LHPs) offer passive cooling technology and have garnered the attention of researchers. Nonetheless, research on LHPs for battery thermal management systems is scarce, and prior investigations have concentrated on a singular heat source. A liquid heat pipe with a dual heat source evaporator has been engineered to simulate the battery arrangement of electric vehicles, which typically comprises multiple battery cells. This study seeks to examine the starting and heat transmission characteristics of LHP. Two battery simulators are fabricated from steel blocks equipped with cartridge heaters. A copper evaporator (121 × 56 × 20 mm) is equipped with a stainless-steel screen mesh capillary wick, and thermocouples are linked to a National Instruments data acquisition (NI DAQ) system for the LHP. Ethanol serves as the working fluid at a filling ratio of 60 %. The startup characteristics of the LHP are examined by altering the heat load, coolant flow rate, and coolant temperature. The experimental findings indicate that the LHP effectively initiates operation at heat loads ranging from 20 to 100 W. The LHP with multiple heat sources demonstrates reduced temperatures compared to a single heat source. The best performance of coolant flow rate and temperature for the quickest startup times are 1.5 L/min and 25 °C, respectively. The lowest thermal resistance achieved is 0.17 °C/W.

Research on multi-heat source arrangement optimization based on equivalent heat source method and reconstructed variational autoencoder

The variational autoencoder (VAE) architecture has significant advantages in predictive image generation. This study proposes a novel RFCNN-βVAE model, which combines residual-connected fully connected neural networks with VAE to handle multi-heat source arrangements. By integrating analytical solutions, polynomial fitting, and temperature field superposition, we accurately simulated the temperature rise distribution of a single heat source. We further explored the use of multiple equivalent heat sources to replace adiabatic boundary conditions. This enables the analytical method to effectively solve the two-dimensional conjugate convective heat transfer problem, providing a reliable alternative to traditional numerical solutions. Our results show that the model achieved high predictive accuracy. By adjusting the β parameter, we balanced reconstruction accuracy and latent space generalization. During the stable phase of the multi-heat source optimization iteration, 73.4% of the results outperformed the dense dataset benchmark, indicating that the model successfully optimized heat source coordinates and minimized peak temperature rise. This validates the feasibility and effectiveness of deep learning in thermal management system design. This research lays the groundwork for optimizing complex thermal environments and contributes valuable perspectives on the effective design of systems with multiple thermal sources or for applications like multi-beam lighting equalization.

Experimental study on a novel self-driven multi-heat sinks system

This article presents a self-driven multi-heat sinks system suitable for cooling multiple heat sources simultaneously. This system can include one driving heat sink and multiple passive heat sinks. The porous medium inside the driving heat sink absorbs heat from its heat source, causing the working fluid to evaporate. The phase changing generating capillary force to drive the circulation of liquid throughout the system. The circulating working fluid flows through the fluid channels in the external passive heat sinks, carrying away the heat from the heat sources at each passive heat sink, thus simultaneously cooling multiple heat sources. This study primarily altered the connections between heat sinks, specifically connecting them in serial and parallel, forming systems with different structures. The operating characteristics of the two differently structured systems were studied through experiments. Results show that both systems effectively dissipate heat, maintaining stable operation at a maximum heat load of 100 W. By comparing the operating characteristics of each heat sink in different structures, it was found that the structure mainly affects the circulation resistance of the working fluid. In the serial system, the high circulation resistance leads to long startup times and high startup temperatures. In contrast, the parallel system effectively addresses these issues and, due to its lower internal circulation resistance, and reduces the operating temperature of the driving heat sink. The parallel system's startup time and temperature are 7% lower than the serial system, and its driving heat sink can handle an additional 10 W of heat load. However, due to the structural impact, each passive heat sink in the parallel system receives lower flow, resulting in higher operating temperatures for the passive heat sinks. Based on the research findings above, the article concludes by outlining the suitable operating conditions for different systems: series-connected and parallel-connected systems are respectively suitable for scenarios where the heat generation of multiple heat sources is similar and where it varies significantly.

Analysing fluid flow and heat transfer comparatively in flow passage systems: Evaluating thermal impacts and geometric configurations

This research thoroughly examines heat transfer and fluid flow in a passage flow system, highlighting the difficulties posed by different geometric arrangements and temperature conditions that may affect the system's performance. The main aim is to evaluate the impacts of different geometric characteristics on the velocity, pressure, and temperature profiles inside the flow route. These factors encompass cavity dimensions, tube diameter, and input conditions. An inclusive comparison of three different geometric designs at controlled temperatures is conducted using computational fluid dynamics (CFD) simulations. The findings indicate that the optimal geometric parameters improve thermal performance, with certain arrangements displaying improvements in heat transfer rates up to 30 %. In this regard, the higher cavity dimensions and suitable input velocities are exposed as advantages. The first sample exhibited a higher velocity of 0.024 m s-1 due to its simpler geometry and favorable heating conditions, while the third sample demonstrated a higher temperature of 465 K due to its complex cavity shape and multiple heating sources. This study suggests that enhancing efficiency in heat management applications necessitates a strategic design approach for passage flow systems, which must account for flow characteristics and geometric specifications. This research would provide insightful information for designers and engineers looking at enhancing fluid flow systems across a range of industrial applications.

Prediction of airflow temperature in coal mining face under the influence of multiple heat sources coupling: Numerical simulation and verification

With the development of coal resources to the deep, the mine heat damage has become increasingly serious. In this work, we proposed a comprehensive airflow temperature prediction model considering the coupling effect of multiple heat sources in coal mining face. The model was then discretized and a coupled solution simulator was developed independently. Finally, we conducted field test to verify the simulation results, and carried out a multi-factor sensitivity analysis affecting the thermal environment of coal mining face. The results show that:(i) The maximum relative error of prediction results is less than 4 %, which verifies the reliability of the prediction model. (ii) Heat dissipation from electrical equipment, surrounding rock and hot airflow leakage of gob area account for 43.8 %, 28.8 % and 17.4 % of the total heat load, which are the main causes of heat damage. (iii) The maximum airflow temperature in coal mining face increases in a parabolic trend with average advance speed. (iv) As the original rock temperature increases, the thermal environment of coal mining face deteriorates rapidly. (v) Cooling the inlet airflow or increasing the airflow volume can alleviate the high temperature problem. This research can provide guidance for the treatment of deep mine heat damage.

Research on the division of heat dissipation spaces for multiple heat sources based on the adiabatic characteristic of heat flow lines

Due to the pressing need for compact layouts, the spacing between high-power devices is gradually decreasing, making the mutual influence between multiple heat sources unavoidable. Therefore, this paper proposes a method based on the adiabatic characteristics of heat flow lines and their convergence positions to evaluate the rationality of the thermal space design of each heat source. This method has been validated for applicability in one-dimensional, two-dimensional, and three-dimensional multi-heat-source conjugate convection heat transfer. Heat flow lines have significant advantages in describing energy flow, as they align with the direction of the temperature gradient. In thermal spaces with adiabatic boundaries or mutual influences between multiple heat sources, heat flow lines converge at certain positions. The relationship between adiabatic boundaries and heat flow line convergence positions has been studied, and a more interpretative decoupling scheme for multi-heat-source systems has been proposed. The main feature of this scheme is the separation of each heat source in the same steady-state thermal space and assigning adiabatic boundaries to the solid partition surfaces, allowing efficient observation of the thermal conditions of individual heat sources and targeted layout optimization. Results indicate that this method can utilize changes in heat flow line convergence positions to assess current thermal conditions and can be used to compare the thermal performance of different shaped heat sinks. Simulation results show that under the same mass conditions, thin-fin heat sinks perform 47 % better than thick-fin heat sinks, providing a more comprehensive and intuitive assessment compared to metrics such as thermal resistance and average temperature. The proposed method offers new ideas for multi-heat-source layout optimization, heat flow control, multi-heat-source partitioned simulation, and abnormal heating detection in multiple heat sources.

Experimental investigation on the thermal performance of a large-size aluminum vapor chamber for multi-point heat sources

Abstract With the development of electronic information technology, the integration and power of electronic equipment continue to increase. As an efficient heat transfer element, vapor chambers are widely used in the field of heat dissipation of electronic devices. However, greater challenges have been posed in terms of higher heat dissipation capacity, larger size, and lighter weight. Therefore, a large-scale aluminum vapor chamber with a size of 340 mm×295 mm ×7.5 mm is designed for the heat dissipation of multi-point array heat sources. Multiple parallel porous ribs are sintered to form capillary wicking channels and vapor diffusion paths, which efficiently transfer the heat from the middle of the vapor chamber to the cold plate on the two sides. The transient working characteristics and heat dissipation performance under different working conditions are experimentally investigated. The results show that there is obvious temperature instability, which can be suppressed by the tilt of the vapor chamber and the increase of the heating power. Under the tilt condition, the temperature rises in the vertical direction due to the influence of gravity, while the inclination angle has basically no effect. The vapor chamber can work stably at the total heating power of 2100 W with the smallest thermal resistance 0.03 °C/W. The single-point heat flux can reach 7.3W/cm2 for the 128 heat sources. Compared to a traditional vapor chamber, the proposed aluminum vapor chamber provides a thermal management solution for large-size electronic devices with multiple heat sources.

Comparative analysis of proportional, proportional–integral, and proportional–integral–derivative controllers for thermal regulation in a cylindrical cooling system with multiple O-Ring heat sources

This study is intended to determine the thermal management capability of different closed-loop controllers inside a cylindrical three-dimensional cooling system with multiple O-Ring type heat sources. The motivation for this research stems from the need for efficient thermal regulation in advanced cooling systems, which is critical for applications ranging from electronics cooling to industrial processes. The uniqueness of this study lies in its comprehensive evaluation of different controllers such as proportional (P), proportional–integral (PI), and proportional–integral–derivative within a geometrically complex cooling environment using a novel trial-and-error approach for tuning controller parameters. The observational domain is a hollow cylinder, and the four discrete heat sources are placed at regular intervals along the cylinder's longitudinal axis, with all the remaining walls insulated. At the center of the system is a temperature probe that measures and provides feedback to the control module to continuously compare it to a pre-specified setpoint temperature. The flowing fluid, air, enters through the semi-circular inlet at one end, whose velocity is controlled by a controller response, and is discharged through the semi-circular outlet at the other end at atmospheric conditions. This study uses the Galerkin finite element method, using proper initial and boundary conditions to solve the governing equations, namely, the Navier–Stokes and heat energy equations. We analyze the time-dependent behaviors of the cooling system by measuring controller responses such as overshoot, rise time, oscillation, steady-state error, and settling time. Additionally, the impacts of the Reynolds number (Re), Richardson number (Ri), and Grashof number (Gr) on the overall mean Nusselt number over time are observed to understand the influence of flow regulation due to the controllers' actions. This comprehensive analysis provides insights into the controllers' inlet flow control based on the set temperature at the probe's center location. A unique trial-and-error approach for selecting Kp and Ki values, which is crucial for controller analysis, is also presented. Based on the results, it can be inferred that increasing the Kp value from 0.003 to 0.010 ms−1 K−1 reduces the steady-state error from 40.8% to 13.97%. For a Ki value of 0.006 ms−2 K−1, the PI controller achieves a zero steady-state error with faster settling at 3.29 s, along with an overshoot of approximately 80.51%. Conversely, a lower Kd value of about 0.0001 mK−1 results in a reduction in the settling time and overshoot compared to the PI controller, while a higher Kd value ensures optimum stability with a higher settling time and a stable Nusselt number of 1.93. This trial-and-error approach to parameter tuning provides valuable insights into the design of controlled environments and the effective management of thermal conditions in various thermo-fluidic applications.

Research on thermal runaway characteristics and mechanism of NCM811 Lithium-ion batteries under cross-seasonal and wide-temperature condition at −10 °C ∼ 33 °C: A case study in Qingdao, China

Multiple heat sources and extreme ambient temperatures pose more severe challenges to the safety performance of lithium-ion batteries (LIBs), and the kinetic characterization of thermal runaway (TR) of LIBs at extreme temperatures has yet to be improved. Through the establishment of a dual heat source coupled stimulation experimental platform, this study investigates the TR mechanism and flame jet dynamics of LIBs under broad temperature ranges corresponding to spring, summer, autumn, and winter (−10 °C ∼ 30 °C). The results indicate that the increase in ambient temperature leads to a gradual reduction in the TR onset time (tonset), in the order of Tonset-Winter>Tonset-Spring>Tonset-Autumn>Tonset-Summer; for example, with 100% SOC (State of Charge), Tonset-Winter = 2528 s, Tonset-Summer = 2211 s, which was accelerated by 14.3%. However, TR maximum temperature (Tmax) showed the opposite trend, Tmax-summer = 687.2 °C, Tmax-winter = 796.5 °C, which decreased by 15.9%. When SOC ≥ 75%, the average warning time for TR disaster of LIB (from venting to the beginning of TR) is 254 s less than that of winter in the summer with higher temperature, which makes the adoption of emergency measures and escape more urgent. When SOC ≥ 50%, the TR process was accompanied by flame generation, and the flame eruption process was the most intense at 100% SOC, with a maximum flame area of about 4400 cm2, and its flame temperature was likewise the highest at 986.4 °C. Carbon and metal oxides were detected in the TR ejecta, and the lower the ambient temperature, the finer the ejecta particles were. The results of the study provide an important scientific reference for improving the theory of TR of LIBs, guiding the investigation of TR and fire in new energy vehicles, and formulating relevant standards.

Comparison of Maximum Heat Transfer Rate of Thin Vapor Chambers with Different Wicks under Multiple Heat Sources and Sinks

In this paper, we present a new analytical model to investigate the maximum heat transfer rate of a thin vapor chamber (TVC) with multiple heat sources and sinks. The model can specifically consider different heat flux conditions for each heat source. Both capillary limitations and allowable maximum temperature constraints were employed to determine the maximum heat transfer rate. The liquid and vapor pressure distributions within the TVC were analytically derived using the Brinkman-extended Darcy equation and the Hagen–Poiseuille equation, respectively. Additionally, the theoretical wall temperature distribution was calculated based on the 3D energy equation, considering different heat flux conditions for multiple heat sources with a weighting factor. Our results demonstrate that the heat flux conditions applied to the heat sources significantly impact the internal flow pattern of the TVC. These changes in flow patterns influence the pressure distributions of the liquid and vapor, thereby affecting the maximum heat transfer rate. Furthermore, the effects of wick parameters on the maximum heat transfer rate under various heat flux conditions were examined.

Startup characteristics of a water loop heat pipe with dual heat sources for battery thermal management system in electric vehicle

Abstract The usage of electric vehicles has significantly reduced emissions of greenhouse gases and other pollutants. However, the high heat release generated by the electric vehicle batteries poses a challenge. To solve this problem, scientists have created a passive cooling thermal management system specifically for electric vehicle based on heat pipes, particularly loop heat pipes. A battery pack often consists of several battery modules, which results in multiple heat sources being dispersed according to their power capacity. Startup behavior of loop heat pipe has been investigated extensively in the literature. However, most of the studies use only one heat source. This paper aims to fill the research gap, particularly when the system is implemented in dual heat sources managed by only one evaporator. To achieve the research objectives, a custom loop heat pipe was constructed. This cooling system’s design is briefly described. The evaporator is made of copper, deionized water was selected as the working fluid because of its high merit number, which indicates strong performance as a heat pipe working fluid and the stainless-steel wire mesh serves as the porous wick. Battery simulator was built using aluminum material and a cartridge heater to mimic the heat produced by the battery. Two case studies were done. First, only one battery simulator was used. Second, two battery simulators were placed on both sides of the evaporator. A type-K thermocouple attached to the NI DAQ 9214 module was used to measure the temperature while the electric heat load varied between 10 W and 50 W. The study investigated the interaction between the heat load distribution and the startup behavior of the loop heat pipe. Startup behavior is crucial for the performance of the loop heat pipe. Based on the experimental results, the loop heat pipe demonstrates outstanding startup performance. It can effectively initiate operation even at a minimal heat load as low as 30 W for the first and second case study. The findings of the study indicate that the dual heat source arrangement effectively mitigates overshoot temperatures and enhances heat transfer performance by increasing the contact area.

Development of a Thermal Energy Storage Model for Performance Prediction of Heat Pump Systems Linked with Multiple Heat Sources

Development of a Thermal Energy Storage Model for Performance Prediction of Heat Pump Systems Linked with Multiple Heat Sources

Solar-heat pump combined drying with phase change heat storage: Multi-energy self-adaptive control

Due to the various uncertainties in multi-energy drying systems, traditional condition control struggles with the rational matching of multiple heat sources and precise temperature regulation. In order to automatically switch energy utilization modes based on current parameters to reduce energy consumption, this paper developed a fuzzy control system for a kelp multi-energy drying device. An automatic switching strategy between different operating modes and the action processes of various actuators were established for matching multiple energy sources. The system hardware and software were designed and installed, including a remote monitoring devices and human-machine interface. Drying experiments of kelp were conducted in solar, solar-heat pump, heat pump and Heat storage-heat pump mode using both the fuzzy control system and the original. The fuzzy control system showed a temperature overshoot of 2.57 %–3.95 %, temperature deviation within ±1.5 °C, which were superior to the original control system. The energy consumption in solar-heat pump mode was 0.398 kW h/kg, only 43 % of the original control system. BP neural networks prediction model of kelp moisture content under different drying modes was established to prevent over-drying. The model can accurately describe the pattern of moisture content variation with RMSE of 2.36–4.27.

Level-set topology optimization of heat sinks with phase-change material

Phase-change materials (PCMs) excel in storing significant thermal energy through the latent heat of fusion during phase changes. However, they often suffer from low thermal conductivity, requiring the incorporation of materials with higher thermal conductivity to overcome this limitation. In this study, we employ the level-set method to topologically optimize the distribution of both PCM and high thermal conductivity materials within heat sinks.The heat transfer process is modeled as an unsteady diffusion problem, with PCM integrated using the apparent heat capacity method. The finite element method, implemented using FEniCS, is utilized to compute the temperature distribution at each time step. The optimization problem is solved using ParaLeSTO, a modular topology optimization software written in C++, seamlessly interfacing with FEniCS through its Python interface.To compute boundary point sensitivities for level-set topology optimization, the discrete adjoint method is employed, combining a perturbation scheme with automatic differentiation. The proposed methodology is first applied to a two-dimensional example of temperature oscillation minimization with a heat flux boundary condition, drawn from existing literature. Subsequently, a two-dimensional example with multiple volumetric heat sources is studied, followed by an extension to a three-dimensional design domain.Comparisons with optimized designs without PCM, serving as a reference, highlight the superior thermal performance of heat sink designs with PCM. The results showcase a maximum temperature reduction of up to 42%, a mean temperature reduction of up to 42%, and a temperature variance reduction of up to 94%. This research contributes to heat sink design by offering discrete solutions that significantly improve thermal performance as compared to designs without PCM. Its impact extends to addressing crucial challenges in thermal management across various applications, including automotive cooling systems, aerospace components, and consumer electronics.

Industrial Park low-carbon energy system planning framework: Heat pump based energy conjugation between industry and buildings

The accelerating urbanization, rapid industrial development, and excessive consumption of fossil fuels pose survival challenges such as energy depletion and environmental degradation for humanity. In the context of industrial park development, constructing a low-carbon energy system, increasing the proportion of renewable energy, enhancing energy-level matching, and utilizing heat pumps for deep waste heat recovery are effective approaches to reduce fossil energy consumption and alleviate environmental pressures. Addressing issues such as diverse thermal flows in industrial sites, complex electricity-heat-cooling energy demands, and unclear industrial-building energy coupling mechanisms, this paper proposes a two-stage planning framework, comprising the following five steps: (1) constructing a waste heat utilization system centered around heat pumps, (2) establishing a mechanism for matching heat sources, equipment, and thermal sinks, (3) establishing an energy conversion model and energy quality quantification system, (4) optimizing waste heat utilization path allocation, and (5) conducting a system energy flow analysis. Case studies demonstrate that the proposed system achieves optimized matching of multiple heat sources and sinks in industrial and building scenarios through thermal integration, meeting diverse energy demands in the park, including electricity, cooling, and multi-grade heat. After coupling with traditional steam pipeline networks, the annual total cost and annual steam power consumption decrease by 33% and 39% respectively, with a waste heat contribution rate of up to 26% and a renewable energy penetration rate of up to 25%, and a waste heat recovery system payback period of 6 years. By establishing an energy quality quantification system and conducting multi-objective optimization considering losses and economic costs, this paper provides Pareto frontier solutions, offering references for engineering proposals. The proposed networked waste heat recovery system is characterized by low energy consumption and high economic efficiency, effectively integrating the energy characteristics of industrial parks and demonstrating engineering applicability.

A multi-period topology and design optimization approach for district heating networks

The transition to modern, low-carbon district heating creates a growing need for scalable, automated design tools that accurately capture the spatial and temporal details of heating network operations. This paper presents an automated design approach for the optimal design of district heating networks that combines scalable density-based topology optimization with a multi-period approach. In this way, temporal variations in demand, supply, and heat losses can be taken into account while optimizing the network design based on a nonlinear physics model. The transition of the automated design approach from worst-case to multi-period shows a design progression from separate branched networks to a single integrated meshed network topology connecting all producers. These integrated topologies emerge without imposing such structures a priori. They increase network connectivity, and allow for more flexible shifting of heat loads between different producers and heat consumers, resulting in more cost-effective use of heat. In a case study, this integrated design resulted in an increase in waste heat share of 42.8 % and a subsequent reduction in project cost of 17.9 %. We show how producer unavailability can be accounted for in the automated design at the cost of a 3.1 % increase in the cost of backup capacity. The resulting optimized network designs of this approach connect multiple low temperature heat sources in a single integrated network achieving high waste heat utilization and redundancy, highlighting the applicability of the approach to next-generation district heating networks.

Optimal dispatch of integrated electricity and heating systems considering the quality-quantity regulation of heating systems to promote renewable energy consumption

The integrated electricity and heating system (IEHS) can improve energy efficiency and promote renewable energy consumption. When quality-quantity regulation (QQR) is adopted, namely adjusting hydraulic and thermal conditions of heating system, the increase in operation flexibility is more remarkable. However, present IEHS dispatch models considering QQR overlook hydraulic characteristics of valves and variable frequency pumps resulting in inexecutable dispatch results easily and hindering IEHS's flexibility potential. Furthermore, loop networks and the access of multiple heat sources in heating systems may lead to flow reversal, but current research adopts a fixed flow direction which suppresses the potential of flow reversal to improve flexibility. In this paper, we propose an IEHS dispatch model considering QQR to promote renewable energy consumption, which considers hydraulic characteristics of valves and variable frequency pumps, and flow reversal. Specifically, we introduce two binary flow direction labels for every branch in heating system model and then the IEHS dispatch model which can deal with flow reversal is established. A sequential solution process combining linear and nonlinear optimization is formulated to overcome the non-convex feature of IEHS dispatch model. Specifically, piecewise linearization and piecewise McCormick relaxation are combined to handle complex nonlinear terms in the dispatch model. Therefore, a mixed integer linear programming model is obtained and solved, of which results are used as initial values for nonlinear optimization. Results in the case study show that operation cost is decreased by 0.97 % and renewable power consumption rate is increased from 83.31 % to 84.42 % after considering valve adjustment. Operation cost is further decreased by 6.06 % and renewable power consumption rate is increased to 94.04 % after considering flow reversal.

A model‐based failure times identification for a system governed by a 2D parabolic partial differential equation

AbstractThis research focuses on the identification of failure times in thermal systems governed by partial differential equations, a task known for its complexity. A new model‐based diagnostic approach is presented that aims to accurately identify failing heat sources and accurately determine their failure times, which is crucial when multiple heat sources fail and there is a delay in detection by distant sensors. To validate the effectiveness of the approach, a comparative analysis is carried out with an established method based on a Bayesian filter, the Kalman filter. The aim is to provide a comprehensive analysis, highlighting the advantages and potential limitations of the methodology. In addition, a Monte Carlo simulation is implemented to assess the impact of sensor measurements on the performance of this new approach.

A virtual test rig for performance and efficiency assessment of heat pump thermal management system for battery electric vehicles

In a Battery Electric Vehicle (BEV), the optimization of its thermal state plays a crucial role in the achievement of relevant vehicle targets such as range, passenger comfort, and recharging times, as well as varying external ambient conditions. Therefore, selecting the most proper solution between the many possible architectures to manage the different thermal loads of a BEV needs the support of a robust simulation platform. In such a framework, a comprehensive numerical twin of an electric city car was developed in the GT-Suite environment and validated against experimental data. Through that, the promising performance of a Heat Pump (HP) based thermal layout has been demonstrated, against a standard Air Conditioning system integrated with a PTC heater, on a wide range of external ambient temperatures (reaching up to +20 % driving range improvement in cold conditions). The present layout proposed a sustainable alternative to the most common R134a as working fluid (i.e., propane) and the integration of multiple heat sources. In addition, different battery preconditioning strategies have been tested, tailored to the selected real-world mission profiles, obtaining a remarkable gain in terms of driving range for the HP system in cold conditions (up to 6 % at −10 °C and 4 % at −20 °C).

Enhancing the waste heat utilization of industrial park: A heat pump-centric network integration approach for multiple heat sources and users

The industrial sector, which is characterized by high energy consumption, primarily using fossil fuels, exhibits significant carbon emissions and severe pollution. Industrial parks generate abundant waste heat with varying flow rates and multiple grades, and also include industrial users with diverse heat demand profiles. Waste heat recovery is an effective method for reducing fossil fuel consumption. However, the current waste heat recovery methods focus on single-heat-source scenarios, making them unsuitable for use in industrial parks with multiple heat sources and heating loads. To achieve efficient matching between different sources and loads, this study developed a heat-pump-centric network system and establishes a two-stage optimization method for networked waste heat utilization. First, based on matrix algebra, a method for matching the generated waste heat with heat pump combinations and heat users was developed to obtain a networked heating path. Second, an optimization model for heat pump combinations was established, and linear integer programming algorithms were employed to obtain the optimal configuration and operational plan for the heating path. Finally, energy flow analysis was conducted to elucidate the optimal energy distribution. The results show that, compared to traditional heating modes, the proposed method achieved a 55 % reduction in energy consumption with a payback period of 4.6 years. The proposed system could enhance the matching between different grades of waste heat and heating demand, thereby improving the thermal energy utilization efficiency. The proposed method demonstrates significant energy saving with efficient utilization and economic benefits and can be applied to different scenarios with multiple sources and loads.