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Search Results (379)

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Keywords = TRNSYS

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16 pages, 3470 KiB  
Article
Performance Analysis of Multi-Source Heat Pumps: A Regression-Based Approach to Energy Performance Estimation
by Reza Alijani and Fabrizio Leonforte
Sustainability 2025, 17(15), 6804; https://doi.org/10.3390/su17156804 - 26 Jul 2025
Viewed by 305
Abstract
The growing demand for energy-efficient heating, ventilation, and air conditioning (HVAC) systems has increased interest in multi-source heat pumps as a sustainable solution. While extensive research has been conducted on heat pump performance prediction, there is still a lack of practical tools for [...] Read more.
The growing demand for energy-efficient heating, ventilation, and air conditioning (HVAC) systems has increased interest in multi-source heat pumps as a sustainable solution. While extensive research has been conducted on heat pump performance prediction, there is still a lack of practical tools for early-stage system evaluation. This study addresses that gap by developing regression-based models to estimate the performance of various heat pump configurations, including air-source, ground-source, and dual-source systems. A simplified performance estimation model was created, capable of delivering results with accuracy levels comparable to TRNSYS simulation outputs, making it a valuable and accessible tool for system evaluation. The analysis was conducted across nine climatic zones in Italy, considering key environmental factors such as air temperature, ground temperature, and solar irradiance. Among the tested configurations, hybrid systems like Solar-Assisted Ground-Source Heat Pumps (SAGSHP) achieved the highest performance, with SCOP values up to 4.68 in Palermo and SEER values up to 5.33 in Milan. Regression analysis confirmed strong predictive accuracy (R2 = 0.80–0.95) and statistical significance (p < 0.05), emphasizing the models’ reliability across different configurations and climatic conditions. By offering easy-to-use regression formulas, this study enables engineers and policymakers to estimate heat pump performance without relying on complex simulations. Full article
(This article belongs to the Special Issue Sustainability and Energy Performance of Buildings)
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16 pages, 5647 KiB  
Article
Performance Degradation of Ground Source Heat Pump Systems Under Ground Temperature Disturbance: A TRNSYS-Based Simulation Study
by Yeqi Huang, Zhongchao Zhao and Mengke Sun
Energies 2025, 18(15), 3909; https://doi.org/10.3390/en18153909 - 22 Jul 2025
Viewed by 187
Abstract
Ground temperature (GT) variation significantly affects the energy performance of ground source heat pump (GSHP) systems. Both long-term thermal accumulation and short-term dynamic responses contribute to the degradation of the coefficient of performance (COP), especially under cooling-dominated conditions. This study develops a mechanism-based [...] Read more.
Ground temperature (GT) variation significantly affects the energy performance of ground source heat pump (GSHP) systems. Both long-term thermal accumulation and short-term dynamic responses contribute to the degradation of the coefficient of performance (COP), especially under cooling-dominated conditions. This study develops a mechanism-based TRNSYS simulation that integrates building loads, subsurface heat transfer, and dynamic heat pump operation. A 20-year case study in Shanghai reveals long-term performance degradation driven by thermal boundary shifts. Results show that GT increases by over 12 °C during the simulation period, accompanied by a progressive increase in ΔT by approximately 0.20 K and a consistent decline in COP. A near-linear inverse relationship is observed, with COP decreasing by approximately 0.038 for every 1 °C increase in GT. In addition, ΔT is identified as a key intermediary linking subsurface thermal disturbance to efficiency loss. A multi-scale response framework is established to capture both annual degradation and daily operational shifts along the Load–GT–ΔT–COP pathway. This study provides a quantitative explanation of the thermal degradation process and offers theoretical guidance for performance forecasting, operational threshold design, and thermal regulation in GSHP systems. Full article
(This article belongs to the Section B: Energy and Environment)
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29 pages, 6649 KiB  
Article
Optimizing Kang-to-Room Area Ratios for Thermal Comfort in Traditional Chinese Architecture: An Empirical and Simulation-Based Approach
by Ning Li, Zhihua Zhao, Dongxu Wang, Qian Zhang and Lin Li
Buildings 2025, 15(15), 2593; https://doi.org/10.3390/buildings15152593 - 22 Jul 2025
Viewed by 218
Abstract
Traditional Chinese Kang heating systems have been used for over two millennia in northern China, yet their thermal efficiency and optimal design parameters lack scientific validation. This study aims to establish evidence-based guidelines for Kang-to-room area ratios to enhance thermal comfort and energy [...] Read more.
Traditional Chinese Kang heating systems have been used for over two millennia in northern China, yet their thermal efficiency and optimal design parameters lack scientific validation. This study aims to establish evidence-based guidelines for Kang-to-room area ratios to enhance thermal comfort and energy efficiency in rural architecture. We conducted direct measurements in a controlled experimental house (24 m2) in Huludao City, collecting temperature and humidity data from Kang surfaces and interior spaces over five-day periods. A benchmark curve for heat flux density was developed based on specific fuelwood consumption rates (1 kg/m2). TRNSYS simulations were employed to validate experimental data and analyze thermal performance in the historical Qingning Palace (352 m2) at Shenyang Imperial Palace. The benchmark curve demonstrated high accuracy with a Mean Absolute Error of 0.46 °C and Root Mean Square Error of 0.53 °C when compared to measured temperatures over the 48 h validation period; these values are well within acceptable ranges for calibrated thermal models. Simulations revealed optimal thermal comfort conditions when heat dissipation parameters were scaled appropriately for building size. The optimal Kang-to-room area ratio ranges from 0.28 to 0.69, with the existing Qingning Palace ratio (0.34) falling within this range, validating traditional design wisdom. This research provides a scientific foundation for sustainable architectural practices, bridging traditional knowledge with contemporary thermal engineering principles for both heritage preservation and modern rural construction applications. Full article
(This article belongs to the Section Building Energy, Physics, Environment, and Systems)
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24 pages, 5217 KiB  
Article
Application of FAHP in Multi-Objective Optimization of Solar–Electromagnetic Energy Heating System Performance
by Na He, Guohui Feng, Shasha Chang, Xinxin Liu and Yanru Cheng
Energies 2025, 18(14), 3712; https://doi.org/10.3390/en18143712 - 14 Jul 2025
Viewed by 287
Abstract
In this study, we applied the fuzzy analytic hierarchy process (FAHP) to the multi-objective optimization of the performance of a solar-electromagnetic energy heating system (SEHS). Optimizing the performance of SEHS as a sustainable heating solution in rural areas is crucial for improving energy [...] Read more.
In this study, we applied the fuzzy analytic hierarchy process (FAHP) to the multi-objective optimization of the performance of a solar-electromagnetic energy heating system (SEHS). Optimizing the performance of SEHS as a sustainable heating solution in rural areas is crucial for improving energy efficiency and reducing environmental impacts. To achieve the optimal balance between economy, system performance, energy efficiency, and comfort, we developed a FAHP-based optimization model using system simulation data from the experimentally validated TRNSYS model. The results show that the optimal decision scheme improved the overall performance by 38% compared to the original design scheme. This work confirms the effectiveness of FAHP in dealing with uncertainty and multi-objective decision-making in SEHS and provides valuable scientific support for engineering practice. Full article
(This article belongs to the Special Issue Solar Thermal Energy Storage and Heating Systems)
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23 pages, 4306 KiB  
Article
A Dynamic Investigation of a Solar Absorption Plant with Nanofluids for Air-Conditioning of an Office Building in a Mild Climate Zone
by Luca Cirillo, Sabrina Gargiulo, Adriana Greco, Claudia Masselli, Sergio Nardini, Vincenzo Orabona and Lucrezia Verneau
Energies 2025, 18(13), 3480; https://doi.org/10.3390/en18133480 - 1 Jul 2025
Viewed by 318
Abstract
This study explores the impact of using water-Al2O3 nanofluids, at different nanoparticle concentrations, in solar thermal collectors for solar cooling applications. Improving the seasonal energy performance of solar cooling systems is a current research priority, and this work investigates whether [...] Read more.
This study explores the impact of using water-Al2O3 nanofluids, at different nanoparticle concentrations, in solar thermal collectors for solar cooling applications. Improving the seasonal energy performance of solar cooling systems is a current research priority, and this work investigates whether nanofluids can significantly enhance system efficiency compared to traditional heat transfer fluids. A transient simulation was carried out using a dynamic model developed in TRNSYS (TRANsient SYstem Simulation), evaluating the system performance throughout the cooling season. The results show that in July, under low volumetric flow conditions and with nanoparticle concentrations of 0.6% and 0.3%, the solar fraction reaches a maximum value of 1. Using a nanofluid at 0.6% concentration leads to significantly higher fractional energy savings compared to pure water. Despite increased pumping energy, the overall energy savings—which include the contribution from an auxiliary boiler—exceed 80% when nanofluids are used. This study goes beyond previous work by providing a dynamic, system-level simulation of nanofluid-enhanced solar cooling performance under realistic operating conditions. The findings demonstrate the practical potential of nanofluids as a valid and more energy-efficient alternative in solar thermal applications. Full article
(This article belongs to the Special Issue Advanced Thermal Simulation of Energy Systems: 2nd Edition)
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20 pages, 4615 KiB  
Article
Energy Savings Potential of Multipurpose Heat Pumps in Air-Handling Systems
by Eva Schito and Paolo Conti
Energies 2025, 18(13), 3259; https://doi.org/10.3390/en18133259 - 21 Jun 2025
Viewed by 357
Abstract
Multipurpose heat pumps are devices able to provide simultaneously heating and cooling requirements. These devices concurrently provide useful thermal energy at condenser and evaporator with a single electrical energy input, potentially achieving energy savings as heat-recovery and co-generative technology. Despite their potential contribution [...] Read more.
Multipurpose heat pumps are devices able to provide simultaneously heating and cooling requirements. These devices concurrently provide useful thermal energy at condenser and evaporator with a single electrical energy input, potentially achieving energy savings as heat-recovery and co-generative technology. Despite their potential contribution to the energy transition goals as both renewable and energy-efficient technology, their use is not yet widespread. An application example for multipurpose heat pumps is air handlers, where cooling and reheat coils are classically fed by separate thermal generators (i.e., boiler, heat pumps, and chillers). This research aims at presenting the energy potential of multipurpose heat pumps as thermal generators of air handler units, comparing their performances with a classic separate configuration. A museum in the Mediterranean climate is selected as a reference case, as indoor temperature and relative humidity must be continuously controlled by cold and hot coils. The thermal loads at building and air handler level are evaluated through TRNSYS 17 and MATLAB 2022b, through specific dynamic models developed according to manufacturer’s data. An integrated building-HVAC simulation, on the cooling season with a one-hour timestep, demonstrates the advantages of the proposed technology. Indeed, the heating load is almost entirely provided by recovering energy at the condenser, and a 22% energy saving is obtained compared to classic separate generators. Furthermore, a sensitivity analysis confirms that the multipurpose heat pump outperforms separate generation systems across different climates and related loads, with consistently better energy performance due to its adaptability to varying heating and cooling demands. Full article
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22 pages, 1465 KiB  
Article
Mechanical Vapour Compression Modelling and Assessment in a Zero-Liquid-Discharge Desalination System
by Pablo Calleja-Cayón, Paula Hernández-Baño, Angel Molina-García and Francisco Vera-García
Processes 2025, 13(7), 1963; https://doi.org/10.3390/pr13071963 - 21 Jun 2025
Viewed by 710
Abstract
Nowadays, treating residual brine from desalination systems is an important issue for sustainable water management, where Mechanical Vapour Compression (MVC) systems are a great energy-efficient option for small-scale desalination plants. In this paper, an MVC model with TRNSYS 18 software is proposed, validated [...] Read more.
Nowadays, treating residual brine from desalination systems is an important issue for sustainable water management, where Mechanical Vapour Compression (MVC) systems are a great energy-efficient option for small-scale desalination plants. In this paper, an MVC model with TRNSYS 18 software is proposed, validated using real data from an MVC experimental system. A relevant contribution of this paper is that each component of the MVC system is individually modelled considering the challenges faced in the real experimental facility and only using input variables that are managed by real MVC plant operators, achieving accurate output results with the proposed model. Assessment of the model uses real datasets from a real MVC experimental facility in Spain, with more than 30,000 individual real values during validation. As a result, the model generated more than 350,000 values each day used for validation purposes. Comparing output variables, such as distillate production and final salinity, the accuracy of the model achieves a mean absolute error of 6.87% and relative errors lower than 2.90%. This contribution highlights the importance of using accurate simulation tools, providing valuable information to optimize MVC systems. Full article
(This article belongs to the Special Issue Recent Advances in Wastewater Treatment and Water Reuse)
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27 pages, 2641 KiB  
Article
Comprehensive Evaluation of Cogeneration Biogas Multiple Supply System for Rural Communities in Northwest China
by Jinping Li and Xiaotong Han
Energies 2025, 18(12), 3124; https://doi.org/10.3390/en18123124 - 13 Jun 2025
Viewed by 298
Abstract
In the context of rapid urbanization in China, many farmers still live in areas far away from urban energy supply networks. To meet the multi-level energy demands of rural communities, this study proposes a combined heat, power, and electricity (CCHP) supply system that [...] Read more.
In the context of rapid urbanization in China, many farmers still live in areas far away from urban energy supply networks. To meet the multi-level energy demands of rural communities, this study proposes a combined heat, power, and electricity (CCHP) supply system that uses solar and biomass energy as inputs, tailored to the natural resources and climatic conditions of the northwestern region. A theoretical model of this system was established in Nanan Community, Wuwei City, and its dynamic performance throughout the year was simulated and analyzed using TRNSYS software. The system was also evaluated for its economic viability, energy efficiency, and environmental impact. The results show that compared with the original and traditional energy supply systems, the CCHP system achieves average primary energy saving rates of −9.87% and 41.52% during the heating season, annual cost savings of 50.35% and 64.19%, carbon dioxide emission reduction rates of 32.89% and 66.86%, and a dynamic investment payback period of 3.14 years. This study provides development ideas for constructing modern integrated energy systems in rural areas that are remote from urban energy supply networks and offers references for investors. Full article
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32 pages, 3011 KiB  
Article
Sensitivity Analysis of a Hybrid PV-WT Hydrogen Production System via an Electrolyzer and Fuel Cell Using TRNSYS in Coastal Regions: A Case Study in Perth, Australia
by Raed Al-Rbaihat
Energies 2025, 18(12), 3108; https://doi.org/10.3390/en18123108 - 12 Jun 2025
Cited by 1 | Viewed by 452
Abstract
This article presents a modeling and analysis approach for a hybrid photovoltaic wind turbine (PV-WT) hydrogen production system. This study uses the TRNSYS simulation platform to evaluate the system under coastal climate conditions in Perth, Australia. The system encapsulates an advanced alkaline electrolyzer [...] Read more.
This article presents a modeling and analysis approach for a hybrid photovoltaic wind turbine (PV-WT) hydrogen production system. This study uses the TRNSYS simulation platform to evaluate the system under coastal climate conditions in Perth, Australia. The system encapsulates an advanced alkaline electrolyzer (ELE) and an alkaline fuel cell (AFC). A comprehensive 4E (energy, exergy, economic, and environmental) assessment is conducted. The analysis is based on hourly dynamic simulations over a full year. Key performance metrics include hydrogen production, energy and exergy efficiencies, carbon emission reduction, levelized cost of energy (LCOE), and levelized cost of hydrogen (LCOH). The TRNSYS model is validated against the existing literature data. The results show that the system performance is highly sensitive to ambient conditions. A sensitivity analysis reveals an energy efficiency of 7.3% and an exergy efficiency of 5.2%. The system has an entropy generation of 6.22 kW/K and a sustainability index of 1.055. The hybrid PV-WT system generates 1898.426 MWh of renewable electricity annually. This quantity corresponds to 252.7 metric tons of hydrogen production per year. The validated model shows a stable LCOE of 0.102 USD/kWh, an LCOH of 4.94 USD/kg, an energy payback time (EPBT) of 5.61 years, and cut CO2 emissions of 55,777.13 tons. This research provides a thorough analysis for developing green hydrogen systems using hybrid renewables. This study also offers a robust prediction model, enabling further enhancements in hybrid renewable hydrogen production. Full article
(This article belongs to the Special Issue Research on Integration and Storage Technology of Hydrogen Energy)
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17 pages, 1310 KiB  
Article
Influence of Building Envelope Modeling Parameters on Energy Simulation Results
by Simon Muhič, Dimitrije Manić, Ante Čikić and Mirko Komatina
Sustainability 2025, 17(12), 5276; https://doi.org/10.3390/su17125276 - 7 Jun 2025
Viewed by 470
Abstract
This study investigates the influence of input values for building energy model parameters on simulation results, with the aim of improving the reliability and sustainability of energy performance assessments. Dynamic simulations were conducted in TRNSYS for three theoretical multi-residential buildings, varying parameters such [...] Read more.
This study investigates the influence of input values for building energy model parameters on simulation results, with the aim of improving the reliability and sustainability of energy performance assessments. Dynamic simulations were conducted in TRNSYS for three theoretical multi-residential buildings, varying parameters such as referent model dimensions, infiltration rates, envelope thermophysical properties, and interior thermal capacitance. The case study, based in Slovenia, demonstrates that glazing-related parameters, particularly the solar heat gain coefficient (g-value), exert the most significant influence—reducing the g-value from 0.62 to 0.22 decreased simulated heating (qH,nd) and cooling (qC,nd) demands by 25% and 95%, respectively. In contrast, referent dimensions for modeled floor area proved least influential. For Building III (BSF = 0.36), dimensional variations altered results by less than ±1%, whereas, for Building I (BSF = 0.62), variations reached up to ±20%. In general, lower shape factors yield more robust energy models that are less sensitive to input deviations. These findings are critical for promoting resource-efficient simulation practices and ensuring that energy modeling contributes effectively to sustainable building design. Understanding which inputs warrant detailed attention supports more targeted and meaningful simulation workflows, enabling more accurate and impactful strategies for building energy efficiency and long-term environmental performance. Full article
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22 pages, 3538 KiB  
Article
Optimisation of Dynamic Operation Strategy for a Regional Multi-Energy System to Reduce Energy Congestion
by Yubang Hu, Qingjie Chen, Jiahui Fan, Shanshan Hu and Yingning Hu
Energies 2025, 18(11), 2857; https://doi.org/10.3390/en18112857 - 30 May 2025
Viewed by 425
Abstract
Focusing on the power consumption of a regional multi-energy system with the characteristics of energy congestion in students’ dormitory buildings in the hot summer and warm winter regions of southern China, a practical regional multi-energy system consisting of three subsystems, namely an integrated [...] Read more.
Focusing on the power consumption of a regional multi-energy system with the characteristics of energy congestion in students’ dormitory buildings in the hot summer and warm winter regions of southern China, a practical regional multi-energy system consisting of three subsystems, namely an integrated screw chiller (ISC), a screw ground-source heat pump (SGSHP), and an air-source heat pump (ASHP), was optimised by the operation control strategy. The system’s power consumption and cooling/heating load characteristics during operation were analysed, and changes in the terminal air-conditioning load were simulated. Based on the dynamic cooling and heating load of the building, a two-stage loading strategy was proposed for optimising the system operation. Taking the load demand matching requirement of the system output and the terminal load demand as constraints, a simulation model of the system was developed using TRNSYS 16 software, and the changes in power consumption and the cooling/heating capacity before and after optimisation were analysed. The results show that the optimised system reduced annual power consumption by approximately 19% and increased condensation heat recovery by about 2.3%. The optimised operation control strategy was aligned well with the terminal cooling and heating demands. Full article
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14 pages, 2105 KiB  
Article
Dynamic Simulations of Phase-Change Emulsions in Cooling Systems
by Yuting Wang, Jingjing Shao, Jo Darkwa and Georgios Kokogiannakis
Buildings 2025, 15(11), 1873; https://doi.org/10.3390/buildings15111873 - 29 May 2025
Viewed by 353
Abstract
The application of phase change material emulsions (PCMEs) in heating, ventilation, and air conditioning (HVAC) systems is considered to be a potential way of saving energy due to their relatively higher energy storage capacity compared with water. They are now widely used as [...] Read more.
The application of phase change material emulsions (PCMEs) in heating, ventilation, and air conditioning (HVAC) systems is considered to be a potential way of saving energy due to their relatively higher energy storage capacity compared with water. They are now widely used as a heat transfer media, so they are able to reduce the flow rate whilst delivering the same amount of cooling energy. In order to evaluate the energy-saving potential of the integrated PCME air conditioning system, whole-building energy simulation was carried out with the building simulation code TRNSYS. Before simulating the whole system, a mathematical model for a PCME-integrated fan coil unit was first developed and validated. A phase change material emulsion called PCE-10 was used, and the TRNSYS simulation showed that the required volumetric flow rate of phase change material emulsions was 50% less than that of water when providing the same cooling effect, which could contribute to a 7% reduction in total energy consumption. Full article
(This article belongs to the Section Building Materials, and Repair & Renovation)
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21 pages, 4192 KiB  
Article
Analysis of Operation Characteristics of Phase-Change Temperature Maintenance System Heating by Solar Source and Sewage Source Heat Pump
by Qingfu Zuo, Qing Wu and Shangwen Zhu
Processes 2025, 13(6), 1676; https://doi.org/10.3390/pr13061676 - 27 May 2025
Viewed by 314
Abstract
To address the issues of high energy consumption and operating costs in the temperature maintenance and heating of floating roof oil tanks, a phase-change temperature maintenance simulation system using a solar source–sewage source heat pump was designed. Its operating characteristics and economic benefits [...] Read more.
To address the issues of high energy consumption and operating costs in the temperature maintenance and heating of floating roof oil tanks, a phase-change temperature maintenance simulation system using a solar source–sewage source heat pump was designed. Its operating characteristics and economic benefits were studied based on the TRNSYS platform. The study analyzed the effects of the solar energy guarantee rate, phase-change heat storage tank operating temperature, and sewage source heat pump operating temperature on various indicators, such as the heat storage and release efficiency of the phase-change heat storage tank, the heating capacity and energy proportion of crude oil, and the power consumption of the sewage source heat pump system. The economic benefits were also compared. The results indicate that when the solar energy guarantee rate is below 30%, the phase-change heat storage tank does not operate, while the sewage source heat pump operates at a higher efficiency, leading to increased system power consumption. However, when the solar energy guarantee rate exceeds 30%, the phase-change heat storage tank operates normally from April to December, while the sewage source heat pump ceases to function, resulting in reduced total system power consumption. Additionally, increasing the phase-change temperature from 38 °C to 54 °C boosts the heat storage and release efficiency of the phase-change heat storage tank from 87% to 94%, without affecting the heat pump’s heating capacity. Similarly, raising the temperature of the sewage source heat pump from 20 °C to 40 °C enhances the heat pump’s heating capacity and efficiency from 4.45 to 4.84, without impacting the heat storage and release efficiency of the phase-change heat storage tank. Full article
(This article belongs to the Special Issue Application of Refrigeration and Heat Pump Technology)
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27 pages, 5395 KiB  
Article
Anti-Freezing and Operation Optimization Design of Air-Conditioning Systems for Industrial Plants in Severely Cold Regions
by Baogang Zhang, Weitao Wang, Ming Liu and Mingxuan Liu
Buildings 2025, 15(11), 1801; https://doi.org/10.3390/buildings15111801 - 24 May 2025
Viewed by 396
Abstract
This study addresses the freeze-up problem in HVAC system heat exchangers of industrial buildings in severely cold regions by proposing a collaborative anti-freeze control strategy based on multi-objective optimization. Taking a diesel engine laboratory as the research case, key freezing-inducing factors were identified [...] Read more.
This study addresses the freeze-up problem in HVAC system heat exchangers of industrial buildings in severely cold regions by proposing a collaborative anti-freeze control strategy based on multi-objective optimization. Taking a diesel engine laboratory as the research case, key freezing-inducing factors were identified through system performance analysis and fault diagnosis. An innovative interlocked anti-freeze control system was developed by integrating electric heating with dynamic regulation of bypass air volume. Utilizing gray relational analysis, the optimal interlock control scheme was selected from four alternatives based on a comprehensive performance evaluation. Multi-objective optimization through the NSGA-II algorithm was performed on parameters including the set temperature, water flow rate, and fresh air volume, achieving coordinated optimization of energy consumption (11.4% reduction compared to pre-optimization) and thermal comfort. TRNSYS-based simulation verification demonstrated that the system maintains a 94.71% freeze protection time assurance rate under extreme operating conditions, effectively resolving the reliability deficiencies of traditional solutions in severely cold environments. This research provides a novel method for industrial building HVAC system anti-freeze design that harmonizes energy efficiency and comfort performance. Full article
(This article belongs to the Section Building Energy, Physics, Environment, and Systems)
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18 pages, 2805 KiB  
Article
Impact of Thermal Mass, Window Performance, and Window–Wall Ratio on Indoor Thermal Dynamics in Public Buildings
by Ran Cheng, Nan Zhang, Wengan Zhang, Yinan Sun, Bing Yin and Weijun Gao
Buildings 2025, 15(10), 1757; https://doi.org/10.3390/buildings15101757 - 21 May 2025
Cited by 1 | Viewed by 560
Abstract
Thermal comfort in public buildings is crucial for occupant well-being and energy efficiency. This study employs TRNSYS software to simulate the effects of thermal mass, window performance, and window–wall ratio (WWR) on summer thermal comfort. The results indicate that without energy-saving measures, increased [...] Read more.
Thermal comfort in public buildings is crucial for occupant well-being and energy efficiency. This study employs TRNSYS software to simulate the effects of thermal mass, window performance, and window–wall ratio (WWR) on summer thermal comfort. The results indicate that without energy-saving measures, increased thermal mass raises daily average maximum and minimum temperatures by 0.33–0.96 °C and 0.14–0.94 °C, respectively. Enhanced WWRs lead to higher daily average maximum and minimum temperatures for double-glazed windows (0.18–0.61 °C and 0.07–0.62 °C, respectively), while single-glazed windows show increased maximum temperatures (0.18–1.86 °C) but decreased minimum temperatures (−0.01 to −0.72 °C). Thermal mass has a modest effect on indoor overheating during high outdoor temperatures. Double-glazed windows and lower WWRs effectively reduce indoor overheating, decreasing the attenuation coefficient by 2.13–28.94%. Conversely, single-glazed windows and higher WWRs enhance heat dissipation, increasing daily average temperature fluctuations by 2.33–44.18%. Notably, single-glazed windows with WWRs ≥ 50% improve thermal comfort by reducing extreme superheat temperature occurrence in heavy-thermal-mass buildings by 0.81 to 14.63%. Despite lower cooling loads with heavy thermal mass, double-glazed windows, and low WWRs, the study suggests that single-glazed windows and high WWRs can enhance summer thermal comfort. Therefore, reasonable shading measures and lighter thermal mass are recommended for such buildings. Full article
(This article belongs to the Section Building Energy, Physics, Environment, and Systems)
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