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A large-scale sphere-shaped experimental facility for neutrino detection is designed as a 23-latitudinal layer composite by using organic glass as the major raw material and is assembled via mass polymerization through a top-to-bottom approach. Heating belts at 4200 W/m2 are used to anneal the bonding joints of external and internal spherical surfaces and produce high-temperature thermal plumes. Buoyancy-driven plumes should be effectively mitigated using ventilation to ensure the near-surface air temperatures above the finished layers can be delicately controlled within 21±1 °C to minimize the deformation of the facility. Schemes to control plumes on both surfaces were investigated using Computational Fluid Dynamics (CFD) method by following a performance-based approach. First, an independent field study was conducted to measure surface temperature and heat flux of mass polymerization and provide references for simulations. Second, dynamic buoyancy-driven plumes produced along the external and internal spherical surfaces were simulated under a no-ventilation scenario. After contacting with the plumes, three periods, in which buoyancy, convection, and advection, were dominating, can be observed according to the changes of near-surface air temperature. Moreover, the temperature and Ra number of the surface-attached plumes were used as indicators to assess the intensity of the plumes quantitatively. Third, three major ventilation schemes, i.e., general, push-pull, and sphere-attached ventilations (with three subdesigns), were compared under the same air change rate level on the basis of the following perspectives: (1) air temperature distributions above the polymerizing layer, (2) overall heat exhaust efficiency, and (3) total spaces where temperature was higher than 22 °C. Results indicated that the combination of push-pull and side-supply ventilations, by which the heat exhaust efficiencies were up to 1.87–3.24, was found to be most effective to control thermal plumes, with approximately 0.1% of the total surrounding air exceeding 22 °C.

Solar lighting technologies can lead sunlight into indoor actively, which has been proved that has great potential to reduce electric lighting consumption and create a healthy visual environment. In this paper, a mathematics model was developed to explore performance characteristics and economic applicability of solar lighting/heating system that combine ordinary solar lighting system with nanofluids to spectroscopically utilize sunlight. The results show that the luminous efficiency of output visible light can reach at 242 lm/W, which is 1.62–2.42 times higher than that of current LED light. Moreover, it can be found that the energy-saving capacity of this system is remarkable when used in most areas of China. As for Harbin, its annual total solar radiation ranges 4190 MJ/m2 to 5020 MJ/m2, the system's annual output energy (per square meter of collection area) is 188.15 kW•h for daylighting and 248.2 kW•h for domestic hot water. Besides, the integrated using of infrared radiation can improve the economy of solar lighting technologies by calculating the comprehensive price of unit output energy.

Shopping complexes are widely built for their convenience and multiple functions. However, their complex functional areas, result in significantly different thermal environments and various customers’ thermal perception. To explain the influence of functional related parameters on the thermal perception of customers in shopping complexes, we selected two typical functional related parameters, including customers’ thermal expectation level of indoor environment in their current area and the area where the customer was ten minutes before taking the survey. 851 valid questionnaires were obtained in two typical shopping complexes during July. Customers’ thermal neutral temperature, thermal preference temperature and thermal comfort temperature range were calculated in different functional areas. Customers’ thermal expectation level was quantified by using expectancy factor. The results showed that customers’ thermal expectation level in entertainment areas was the highest, followed by food courts, retail areas, and transition spaces. Customers’ thermal expectation level would influence their thermal neutral temperature and thermal sensitivity. Customers with different thermal experience differed significantly in their thermal sensation voting (p< 0.01). The highest thermal sensitivity, about 0.41/°C, was found in customers moving from high-temperature areas to low-temperature areas. These findings help to clarify how functional related parameters affect the thermal comfort of customers and provide the guidance for designing the indoor temperature in shopping complexes.

The transportation buildings alongside the expressways (TBE) have comprehensive characteristics, providing shopping and accommodations for drivers and passengers. However, the indoor thermal environment and energy consumption of such service buildings was not covered in most studies. To this end, based on some typical TBEs, this study investigated the thermal environment and energy consumption characteristics for TBEs. And the mentioned TBEs are located in Xiong'an New Area, a national special zone with requirements of low carbon and low energy consumption in China's cold region. The thermal environment study included questionnaire survey and on-site investigation by adopting dynamic thermal comfort evaluation index (i.e., Relative Warmth Index (RWI) and Heat Deficit Rate (HDR)). Then, the TBE energy consumption was investigated with the main influencing factor analyses. Finally, numerical simulations were conducted to analyze the energy efficiency approaches in TBE. The results showed that RWI and HDR were able to evaluate the thermal comfort of personnel in transitional environment of TBE in winter. Meanwhile, when the room temperature was set as 16 °C, it was still able to maintain the thermal environment for the indoor staff. The main energy influencing factors of TBEs are building scale, system equipment and usage characteristics. Besides, it was practicable to adopt the heat pump system to replace conventional space heating and cooling system, of which the total energy consumption of geothermal heat pump reduced by 38.1%.

The application of solar thermal energy to preheat cold fresh air for mechanical ventilation could save a lot of energy and ensure the stable operation of the ventilation system. In this paper, a kind of collector-storage solar air heating system (CSSAHS), in which the thermal storage unit (TSU) is characterized by a dual S-channel for heat transfer, is proposed and the mathematical model for the integrated system was established. The model including the TSU, solar air collector, heat recovery device, and the fan was verified by an experimental study set up in a typical cold city in China. The model has been verified by experiments. The simulation results demonstrate that fresh air is the most important factor affecting storage/release efficiency. The increasing rate of heat release efficiency in the range of fresh air temperature -6–18°C is about 1.58%/°C. The solar heat collector area and the size of the TSU suitable for representative cities in cold regions are optimized based on multi-condition simulation analysis. The CSSAHS can preheat fresh air for 5 h after heat storage and the release efficiency is between 52 and 74%. Compared with other systems, the energy-saving rate of the CSSAHS is 26.5–33.3% in cold winter, and the heat supply ratio of the TSU is 24.4–35.1%.

This work presents a cost-effective and environment-friendly form-stabilized phase change material (PCM) and corresponding solar thermal application in the tankless solar water heater (TSWH). Coconut shell charcoal (CSC) as supporting material was modified by moderate oxidant of H2O2 with different concentrations, and then stabilized stearic acid (SA) to prepare composite PCMs through vacuum impregnation. It found that CSC support causes a 15.70% improvement of SA loadage after treated by 15% H2O2 due to coefficient enhancement by physical interaction and surface modification. The modified CSC15 support appears more super macropores which contribute to the impregnation of SA than non-modified CSC0 support verifying from SEM and BET results. And the content of oxygen functional groups was increased after oxidation modification, also motivating SA stabilization by hydrogen bond interaction in XPS analysis. FTIR results proved there is no chemical reaction happened between SA and CSC. Moreover, the latent heat and phase transition temperature of the as-prepared SA/CSC15 composite are 76.69 J g−1 and 52.52 °C, respectively. All composites exhibit excellent thermal stability under a working temperature of 180 °C and form stability during phase change. Thermal energy storage-release test within 70 °C presents the composite has fast heat transfer efficiency than pure SA. The composite filled in TSWH system has 0.75 W m−1 K−1 thermal conductivity which is 2.88 times higher than that of pure SA (0.26 W m−1 K−1). Besides, the TSWH system with a flow rate of 0.004 kg s−1 could heat water effectively after sunset and the energy obtained from the thermal storage system within 1830 s testing times is about 0.15 kW h. In all, SA/CSC composite with good physical-thermo properties has potential in thermal energy storage application, especially in solar energy storage.

Pre-dehumidification time (τpre) and pre-dehumidification energy consumption (Epre) play important roles in preventing the condensation of moisture on the floors of rooms that use a radiant floor cooling (RFC) system. However, there are few theoretical or experimental studies that focus on these two important quantities. In this study, an artificial neural network (ANN) was used to predict condensation risk for the integration of RFC systems with mixed ventilation (MV), stratum ventilation (SV), and displacement ventilation (DV) systems. A genetic algorithm-back-propagation (GA-BP) neural network model was established to predict τpre and Epre. Both training data and validation data were obtained from tests in a computational fluid dynamics (CFD) simulation. The results show that the established GA-BP model can predict τpre and Epre well. The coefficient of determination (R2) of τpre and of Epre were, respectively, 0.973 and 0.956. For an RFC system integrated with an MV, SV, or DV system, the lowest values of τpre and Epre were with the DV system, 23.1 s and 0.237 kWh, respectively, for a 67.5 m3 room. Therefore, the best pre-dehumidification effect was with integration of the DV and RFC systems. This study showed that an ANN-based method can be used for predictive control for condensation prevention in RFC systems. It also provides a novel and effective method by which to assess the pre-dehumidification control of radiant floor surfaces.

In recent years, countries worldwide have actively advocated electric vehicles for environmental protection. However, restrictions on the driving range and charging have hampered the promotion of electric vehicles. This study proposes a portable, auxiliary photovoltaic power system based on a foldable scissors mechanism for electric vehicles. The system includes a photovoltaic power generation module and an electricity transfer module. The photovoltaic power generation module built based on a foldable scissors mechanism is five times smaller than in its unfolded state, improving its portability in its folded state. The electricity transfer module transfers electricity into the cabin via wireless power transfer units and stores electricity in supercapacitors. Solar simulation experiments were conducted to evaluate the system's performance: maximum output power of 1.736 W is measured when the load is 5 Ω, while maximum wireless power transfer efficiency is up to 57.7% with 10 Ω load. An electric vehicle in Chengdu city was simulated for a case study. The results show that the annual output of a single photovoltaic power system can drive the MINIEV for 423.625 km, indicating that the proposed system would be able to supply power for electric vehicles as an auxiliary power supply system.