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Boron (B), as a low-Z material, is widely employed for wall conditioning to enhance plasma performance in fusion devices. In the Experimental Advanced Superconducting Tokamak, a series of experiments involving real-time B powder injection has been conducted to investigate fuel particle behavior. It was observed that fuel particle recycling decreased with an increase in the amount of B powder injected, resulting in an increase in short-term fuel retention. The fuel recycling decreased by up to 80%, as indicated by divertor neutral pressure and D α line emission. Furthermore, each B atom exhibited a trapping capacity of 0.3 D particles during B powder injection at a typical flow rate. The real-time B injection had no wall hysteresis effect on D retention, implying that cumulative B injection and deposited film did not affect long-term D retention. The possible mechanism for D retention is the formation of B-C-O-D compounds and co-deposition between B and D particles during discharges. This investigation would be valuable for evaluating T retention when B is used as wall conditioning material in future fusion reactor devices.

An innovative approach is proposed for the protection of plasma-facing surface of blankets (solid first wall), which will also serve as an automatic disruption mitigation system. In a strong magnetic field, liquid metal is frozen in the magnetic field. This property enables liquid metal to flow along the field line. In a divertor configuration with a lower single-null, a second separatrix exists above the plasma. Toroidally-continuous liquid metal sheets, poured through a toroidal slot located radially outside the 2nd separatrix flux surface, move along the field line, absorbing heat and particles, reach the divertor at a glancing angle. At the current quench in a disruption, a toroidal current is induced automatically in the liquid metal surrounding the core plasma. The resultant j  ×  B force pushes the liquid metal toward the core plasma, significantly mitigating the heat load and force on the first wall and the divertor. Use of magnetically-guided liquid metal FW would also eliminate the need of fine shaping and toroidal alignment of the first wall.

Nowadays the growth of the cities increased built and paved areas, energy use and heat generation. The phenomenon of urban warming, called urban heat island, influences negatively outdoor comfort conditions, pollutants concentration, energy demand for air conditioning, as well as increases environmental impact due to the demand of energy generation. A sustainable technology for improving the energy efficiency of buildings is the use of green roofs and walls in order to reduce the energy consumption for conditioning in summer and improve the thermal insulation in winter. The use of green roofs and walls can contribute to mitigate the phenomenon of heat island, the emissions of greenhouse gases, and the storm water runoff affecting human thermal comfort, air quality and energy use of the buildings. Recently, a number of municipalities started to adopt regulations and constructive benefits for renovated and new buildings which incorporate green roofs and walls. The aim of this paper is to describe the green roofs and walls plant technology.

Over the past two decades, extensive research has elucidated the significant contributions of various nanomaterial such as metals, metal oxides, carbon nanotubes (single, double, and multi-wall), nanowires, and graphene in improving the tribological and thermal properties of AC & R systems used in both industrial and domestic settings. A recent research paper has specifically focused on the performance enhancement of AAC through the use of Nano-oxides, namely CuO, ZnO, and TiO2, employing mathematical modeling. This study investigates how dispersed Nano-oxides of CuO, ZnO, and TiO2, when added to a base of POE lubricant and HFC-R134a refrigerant, influence the performance of automobile air conditioning systems. The primary focus is on viscosity, heat transfer rate, and thermal conductivity of the working medium. The experimental results are compared with tested data, and further analysis is conducted using TK Solver 6.0 and Origin Lab software. The findings demonstrate that the incorporation of these Nano-oxides has a positive impact on thermal-physical properties (k-Thermal conductivity, ρ-viscosity, ρ-density and Cp-specific-heat) and heat transfer characteristics compared to systems without Nano-materials. Furthermore, there is a notable increase in Coefficient of Performance (COP) ranging from 23–29% with varying volume concentrations of Nano-oxides (0.5% to 2.5%) under atmospheric temperature conditions. Consequently, the combination of copper oxide, Zinc Oxide, and Titania nanoparticles with HFC-R134a as well as R1234ze (E) proves to be an effective approach for optimizing refrigerant properties and improving the performance of automobile air conditioning systems. Thus, Nano-oxides dispersion offer a promising solution for enhancing energy efficiency and reducing the reliance on conventional energy sources in thermal systems.

Purpose The purpose of this study is to make a numerical analysis of a wall jet with a moving wall attached with a heated body. The hot body is cooled via impinging wall jet. Thus, a jet cooling problem is modeled. The Reynolds number is taken in three different values between 5 × 103 ≤ Re ≤ 15 × 103. The h/H ratio for each value of the Re number was taken as 0.02, 0.04 and 0.0, respectively. Design/methodology/approach Two-dimensional impinged wall jet problem onto a moving body on a conveyor is numerically studied. The heated body is inserted onto an adiabatic moving wall, and it moves in +x direction with the wall. Governing equations for turbulent flow are solved by using the finite element method via analysis and system Fluent R2020. A dynamic mesh was produced to simulate the moving hot body. Findings The obtained results showed that the heat transfer (HT) is decreased with distance between the jet outlet and the jet inlet. The best HT occurred for the parameters of h/H = 0.02 and Re = 15 × 103. Also, HT can be controlled by changing the h/H ratio as a passive method. Originality/value Originality of this work is to make an analysis of turbulent flow and heat transfer for wall jet impinging onto a moving heated body.

Plants not only enhance the aesthetic appeal of indoor spaces, but also contribute to the regulation of the indoor thermal environment. In this study, an active plant wall (APW) integrated with air-conditioning system to investigate its influence on the indoor thermal conditions, as well as examine participants′ skin temperature and subjective perceptions. In transition season and winter, the results demonstrated that APW led to a decrease in indoor temperature by 1.35℃ and 1.03℃, respectively. The mean relative humidity (RH) enlarged by 11.6% and 20.76%. In summer, APW caused a rise of 0.18℃ in indoor temperature and led to a decline of 2.7% in RH. Throughout the year, APW controlled air speed at 0.2–0.3 m/s, reducing the CO 2 concentration by 42.35ppm, 43.83ppm and 46.83ppm, respectively. APW brought the mean skin temperature (MST) in Room B closer to neutral skin temperature of 33.2℃ throughout the year. Additionally, APW raised overall air fresh and thermal comfortable levels throughout the year to around “Fresh (+ 1)” and “Slightly comfortable (+ 1)”, respectively. The findings suggested that APW can enhance indoor air quality and thermal comfortable levels throughout the year.

In order to meet the great demand for green grain storage and low carbon emissions, paraffin, high-density polyethylene (HDPE), and expanded graphite (EG) were used to produce shape-stabilized phase change material (SSPCM) plates, which were then used to reconstruct building walls for existing granaries. A new type of SSPCM plate was then prefabricated with different thermal conductivities and a high latent heat. This plate could be directly adhered to the existing granary walls. In order to evaluate the thermal regulation performance of these phase change granary walls, experiments and numerical methods were established, specifically for the summer condition. The thermal behavior of the SSPCM granary wall was compared with that of the common concrete granary wall to obtain the optimal parameters. It was concluded that increasing the thickness of the SSPCM layer can reduce the temperature rise of the wall. However, the maximum latent heat utilization rate and energy storage effects were obtained when the SSPCM thickness was at an intermediate level of 30 mm. The thermal conductivity of the SSPCM had a controversial effect on the thermal resistance and latent heat utilization behaviors of the SSPCM. Considering the temperature level and energy saving rate, a 30 mm thick SSPCM plate with a thermal conductivity of 0.2 W/m·K provided a superior performance. When compared to the common wall, the optimized energy-saving rate was greatly enhanced by 35.83% for the SSPCM granary wall with a thickness of 30 mm and a thermal conductivity of 0.2 W/m·K.

This paper discusses an improved approach to the Trombe wall: an insulated panel is installed on the inner side, and vents are installed at the top and bottom to connect the outer and inner air layer with the interior. Direct current (DC) fans are installed in the upper vents for stable control of the air circulation. The study first analyzed the thermal performance of this composite Trombe wall, for which the heat load was 27.3% less compared to the classic Trombe wall and 32.1% less compared to the case without the Trombe wall. However, its efficiency for heating the room temperature was not high without heating. Then, we optimized the ventilation efficiency, the proportion of the Trombe wall in the room, and the type of glazing. The highest heat load savings could be achieved when the ventilation openings used high ventilation with temperature-controlled fans and the Trombe wall about 3% of the house floor area. With the use of Low-e double-glazing, we were able to save nearly 41.3% of the heat load than that with the regular single-glazing. For the composite Trombe wall, after taking into account the optimization factors, the room temperature was significantly higher, and could save nearly 52.3% of energy compared to the pre-optimization period.

Strategic selection of glazing, its window-to-wall ratio, and wall thickness of building reduce the energy consumption in the built environment. This paper presents the experimental results of solar optical properties of five glasses: clear, tinted bronze, tinted green, bronze reflective, and polymer dispersed liquid crystal glasses. Laterite room models were modeled with four different thicknesses and four different glasses using Design Builder, and thermal simulation tests were carried out using Energy Plus. The energy savings and carbon emission mitigation prospective of a building’s glazing variety, window-to-wall ratio (WWR), and wall thickness were investigated. The results revealed that among the five window glasses studied, the polymer dispersed liquid crystal glazing window (PDLCGW) was found to be the most energy-efficient for low heat gain in laterite rooms. The laterite room with 0.23 m wall thickness and 40% PDLCGW WWR reduced 18.9% heat gain in comparison with the laterite room with 0.23 m wall thickness and 40% clear glass WWR. The laterite room of 0.23 m wall thickness with PDLCGW glazing of 40% WWR enhanced cooling cost savings up to USD 31.9 compared to the laterite room of 0.08 m wall thickness with 40% PDLCGW. The laterite room of 0.23 m wall thickness with PDLCGW glazing of 40% WWR also showed improved carbon mitigation of 516 kg of CO2/year compared to the 0.23 m wall thickness laterite room of 40% WWR with clear glass glazing. The results also showed that the laterite room with 0.23 m wall thickness and 100% clear glass WWR increased heat gain by 28.2% in comparison with the laterite room with 0.23 m wall thickness and 20% clear glass WWR. The results of this article are essential for the strategic design of buildings for energy saving and emission reduction.

Energy efficiency in buildings is very important since it contributes significantly to fossil fuel consumption and consequently climate change. Several approaches have been taken by researchers and the industry to address the issue. These approaches are classified as either passive or active approaches. The purpose of this review article is to summarize a number of the technologies that have been investigated and/or developed. In this technical review paper, the more commonly used active and passive building energy conservation techniques are described and discussed. The pros and cons of both the active and passive energy techniques are described with appropriate reference citations provided. This review article provides a description to give an understanding of building conservation approaches. In the active classification, several methods have been reviewed that include earth-to-air heat exchangers, ground-source and hybrid heat pumps, and the use of new refrigerants, among other methods. In the passive classification, methods such as vegetated roofs, solar chimneys, natural ventilation, and more are discussed. Often, in a building, multiple passive and active methods can be employed simultaneously.