scholarly journals Effect of external thermal insulation layer on the Chinese solar greenhouse microclimate

2021 ◽  
Vol 8 (12) ◽  
Author(s):  
Zilong Fan ◽  
Xingan Liu ◽  
Xiang Yue ◽  
Lei Zhang ◽  
Xiaoyu Xie ◽  
...  
Keyword(s):  
Thermal Insulation ◽  
Outer Surface ◽  
Three Dimensional ◽  
Insulation Layer ◽  
External Insulation ◽  
Solar Greenhouse ◽  
North Wall ◽  
Heat Preservation ◽  
Influence Degree ◽  
Microclimate Environment

In order to optimize the heat preservation capacity of Chinese solar greenhouse (CSG) and further reduce energy consumption, we clarified the mechanism of the external thermal insulation layer that affects the microclimate environment of CSG. The most suitable external insulation layer thickness (EILT) of the solar greenhouse envelope structure in high latitude and cold region has been indicated. A three-dimensional mathematical model was developed based on computational fluid dynamics and verified using experimental measurement. The temperature variations, heat variations and economic benefit were analysed. The results indicated that covering the outer surface of the enclosures with a thermal insulation layer could effectively increase the greenhouse temperature by 1.2–4.0°C. The influence degree of the external thermal insulation layer on the greenhouse microclimate was as follows: sidewall (SW) > north wall (NW) > north roof (NR). In high-dimensional and cold areas, covering the outer surface of all enclosures with insulation layer as the suitable solution could raise the greenhouse air temperature maximally. The suitable EILT of each maintenance structure was obtained as follows: NW 80 mm, SW 80 mm, NR 100 mm.

Influencing analysis of different baffle factors on oil liquid sloshing in automobile fuel tank

2020 ◽  
Vol 234 (13) ◽  
pp. 3180-3193
Author(s):  
Enhui Zhang ◽  
Wenyan Zhu ◽  
Lihe Wang
Keyword(s):  
Three Dimensional ◽  
Fuel Tank ◽  
Liquid Sloshing ◽  
Inertia Force ◽  
Dimensional Finite Element ◽  
Combined Action ◽  
Adverse Influence ◽  
Three Dimensional Finite Element ◽  
Influence Degree ◽  
Sloshing Pressure

Oil liquid sloshing is a common phenomenon in automobile fuel tank under variable working conditions. Installing baffles in automobile fuel tank is the most effective way to suppress adverse influence caused by oil liquid sloshing. Different types of three-dimensional finite element models filling oil liquid are created, meshed, and simulated. The reliability of simulation results is verified by test. The concept of time–area value is proposed in this work. In order to explore the influence of different baffle factors on oil liquid sloshing, six factors are studied. Six kinds of influencing factors are height, structure, shape, spacing, number, and placement of baffles. The sloshing pressure and time–area value are the core parameters for evaluating the influence degree. Some results could be obtained by comparing the parameters of oil liquid sloshing under the same condition. High baffles and baffles with small spacing have obvious attenuation influence on the pressure of oil liquid sloshing. Low baffles, double baffles, parallel baffles, and the combined action of inertia force and gravity are more beneficial to the reduction of time–area value. Time–area value is the largest and the smallest in fuel tank with intersection baffles and low baffles, respectively.

A bridge-arched and layer-structured hollow melamine foam/reduced graphene oxide composite with an enlarged evaporation area and superior thermal insulation for high-performance solar steam generation

2020 ◽  
Vol 8 (5) ◽  
pp. 2701-2711 ◽  
Author(s):  
Sen Meng ◽  
Xing Zhao ◽  
Chun-Yan Tang ◽  
Peng Yu ◽  
Rui-Ying Bao ◽  
...  
Keyword(s):  
Graphene Oxide ◽  
Reduced Graphene Oxide ◽  
Thermal Insulation ◽  
High Performance ◽  
High Efficiency ◽  
Insulation Layer ◽  
Steam Generation ◽  
Oxide Composite ◽  
Reduced Graphene ◽  
Solar Steam Generation

A bridge-arched integrated evaporator that introduces air as the thermal insulation layer exhibits high-efficiency solar steam generation.

Study on Spread of Fire Overflow on Building Facades with Insulation Materials

2013 ◽  
Vol 405-408 ◽  
pp. 2438-2442
Author(s):  
Yan Feng Li ◽  
Cong Cong Xu ◽  
Xue Fei Xing ◽  
Jin Zhang ◽  
Cheng Hu
Keyword(s):  
Numerical Simulation ◽  
Thermal Insulation ◽  
Maximum Temperature ◽  
Computational Results ◽  
Exterior Wall ◽  
Insulation Layer ◽  
Insulation System ◽  
High Rise ◽  
Building Facades ◽  
Fire Barrier

Fire overflow on exterior wall with thermal insulation system has been studied by numerical simulation. The spread laws of fire overflow are analyzed through the temperature distribution near the window. The computational results are compared with those of test in the Exterior Insulation Fire Barrier Technical Guidelines (EIFBTG). It has been found that the calculated maximum temperature points is closed to the test on the first floor, the first ceiling, and the points near the above two windows. However, there are differences between two kinds of results above two floors and ceilings, and the points near the first window. It has also shown that when the HHR is 7.5KW, the scope of damage of exterior thermal insulation layer is about 15 square meters near the window. The research would provide reference for fire protection design of exterior wall thermal insulation in the high-rise buildings.

scholarly journals Nanogold as a Specific Marker for Electron Cryotomography

2009 ◽  
Vol 15 (3) ◽  
pp. 183-188 ◽  
Author(s):  
Yongning He ◽  
Grant J. Jensen ◽  
Pamela J. Bjorkman
Keyword(s):  
Lipid Bilayers ◽  
Outer Surface ◽  
Three Dimensional ◽  
Fc Receptor ◽  
Specific Marker ◽  
Neonatal Fc Receptor ◽  
Membrane Bound ◽  
Nanogold Particles ◽  
Intracellular Vesicles ◽  
Electron Cryotomography

AbstractWhile electron cryotomography (ECT) provides “molecular” resolution, three-dimensional images of unique biological specimens, sample crowdedness, and/or resolution limitations can make it difficult to identify specific macromolecular components. Here we used a 1.4 nm Nanogold® cluster specifically attached to the Fc fragment of IgG to monitor its interaction with the neonatal Fc receptor (FcRn), a membrane-bound receptor that transports IgG across cells in acidic intracellular vesicles. ECT was used to image complexes formed by Nanogold-labeled Fc bound to FcRn attached to the outer surface of synthetic liposomes. In the resulting three-dimensional reconstructions, 1.4 nm Nanogold particles were distributed predominantly along the interfaces where 2:1 FcRn-Fc complexes bridged adjacent lipid bilayers. These results demonstrate that the 1.4 nm Nanogold cluster is visible in tomograms of typically thick samples (∼250 nm) recorded with defocuses appropriate for large macromolecules and is thus an effective marker.

scholarly journals Inverted roof insulation kits and their durability

2018 ◽  
Vol 163 ◽  
pp. 08005 ◽  
Author(s):  
Barbara Francke ◽  
Robert Geryło
Keyword(s):  
Water Absorption ◽  
Thermal Insulation ◽  
Laboratory Tests ◽  
Expanded Polystyrene ◽  
Insulation Layer ◽  
Performance Properties ◽  
Climate Conditions ◽  
Freeze Thaw ◽  
Moisture Increase

In the paper there was analyzed a mechanism of loss of performance properties of inverted roof insulation kits resulted by moisture increase of the insulation layers. This problem is very important in such systems because the thermal insulation is placed above the waterproofing layer and is not protected against water absorption. Abovementioned problem is more and more common in the course of building’s utilization in Polish climate conditions. Because inverted roof kits are based on extruded polystyrene (XPS) and expanded polystyrene (EPS), those materials have been used in tested samples. The results of laboratory tests showed the phenomenon and its effect on durability and sustainability of roof covering performance. It was also found that the biggest influence on the increase of moisture in the thermal insulation layer has not the long term water absorption by immersion but freeze –thaw cycles.

A measurement method for three-dimensional inner and outer surface profiles and spatial shell uniformity of laser fusion capsule

2021 ◽  
Vol 134 ◽  
pp. 106601
Author(s):  
Xianxian Ma ◽  
He Ni ◽  
Mengshuang Lu ◽  
Zihao Liu ◽  
Jingwen Huang ◽  
...  
Keyword(s):  
Outer Surface ◽  
Measurement Method ◽  
Three Dimensional ◽  
Laser Fusion ◽  
Surface Profiles

scholarly journals Investigation of the Insulation Effect of Thermal Insulation Layer in the Seasonally Frozen Region Tunnel: A Case Study in the Zuomutai Tunnel, China

2019 ◽  
Vol 2019 ◽  
pp. 1-14 ◽  
Author(s):  
Pengyu Zhao ◽  
Jianxun Chen ◽  
Yanbin Luo ◽  
Lijun Chen ◽  
Yao Li ◽  
...  
Keyword(s):  
Thermal Insulation ◽  
Air Temperature ◽  
Ground Surface ◽  
Maximum Temperature ◽  
Insulation Layer ◽  
Tunnel Length ◽  
Maximum Temperature Difference ◽  
Insulation Effect ◽  
Two Sides

In this study, a field temperature test was performed to reveal the insulation effect of the thermal insulation layer installed at lining surface. The thermal insulation layer is made of polyphenolic, and the thickness is 7 cm. According to the test results, the temperature of the thermal insulation layer and lining continuously changes with the air temperature in the tunnel in an approximately trigonometric function. The temperature of tunnel lining without thermal insulation layer is close to the air temperature, which results in the lining frost in winter. The maximum temperature difference between the two sides of the thermal insulation layer can be 27°C. In the section whose buried depth is more than 11.4 m, the temperature of lining with thermal insulation layer in winter is mainly influenced by the cold air in the tunnel. When the monthly mean and lowest daily mean air temperature are lower than −10°C and −14.3°C in the coldest month, the temperature at the inner side of the thermal insulation layer is below 0°C. When the buried depth is less than 11.4 m, the temperature of lining is also influenced by the low temperature at ground surface. The temperature of lining is lower. The thicker thermal insulation layer and even active heat measure are needed. Therefore, the design of thermal insulation layer thickness should consider the air temperature distribution and tunnel buried depth along the tunnel length.

scholarly journals Feasibility of Using Modified Silty Clay and Extruded Polystyrene (XPS) Board as the Subgrade Thermal Insulation Layer in a Seasonally Frozen Region, Northeast China

2019 ◽  
Vol 11 (3) ◽  
pp. 804 ◽  
Author(s):  
Qinglin Li ◽  
Haibin Wei ◽  
Leilei Han ◽  
Fuyu Wang ◽  
Yangpeng Zhang ◽  
...  
Keyword(s):  
Numerical Simulation ◽  
Thermal Insulation ◽  
Oil Shale ◽  
Pollution Index ◽  
National Standards ◽  
Silty Clay ◽  
Insulation Layer ◽  
Insulation Property ◽  
Thermal Insulation Property ◽  
Seasonally Frozen Regions

To achieve the purposes of storing industry solid wastes and enhancing subgrade stability in seasonally frozen regions, Structure III, which utilized the modified silty clay (SC) and extruded polystyrene (XPS) board as a novel subgrade thermal insulation layer (NSTIL), was presented. The above modified SC consisted of oil shale industry solid waste, fly ash and SC. In terms of environmental impact, the average single pollution index, the Nemerow integrated pollution index and national standards were carried out to estimate whether the modified SC could be used as a subgrade filler. These results show that, although the modified SC will produce pollution to the environmental background, the concentration of each hydrochemical constituent from the modified SC meets the corresponding national standards in China. In terms of the thermal insulation capability, the numerical simulation of coupling moisture and temperature was applied to analyze that of Structures I, II and III. The research results show that the numerical results of the Structure I are approximated to the official website information of Jilin province, indicating that the above numerical simulation is effective for coupling moisture and temperature of frozen soil. Both modified SC and NSTIL have the advantage of good thermal insulation property, but the thermal insulation property of the NSTIL is greater. Furthermore, the NSTIL at the top of the Structure III can protect the SC of the experimental road from the damage of frost heave. The research results are of great significance for reducing environmental pollution caused by oil shale industry solid waste and fly ash, increasing the utilization rate of industrial waste and enhancing the subgrade stability in seasonally frozen regions.

scholarly journals Impact of Tunnel Temperature Variations on Surrounding Rocks in Cold Regions

2019 ◽  
Author(s):  
Qingyang Yu ◽  
Chao Zhang ◽  
Zhenxue Dai ◽  
Chao Du ◽  
Mohamad Reza Soltanian ◽  
...  
Keyword(s):  
Thermal Conductivity ◽  
Temperature Field ◽  
Temperature Distribution ◽  
Three Dimensional ◽  
Temperature Fields ◽  
Insulation Layer ◽  
Cold Regions ◽  
Ambient Temperatures ◽  
Temperature Conditions ◽  
Layer Control

Temperature is an important factor in designing and maintaining tunnels, especially in cold regions. We present three-dimensional numerical simulations of tunnel temperature fields at different temperature conditions. We study the tunnel temperature field in two different conditions with relatively low and high ambient temperatures representing winter and summer of northeast China. We specifically study how these temperature conditions affect tunnel temperature and its migration to surrounding rocks. We show how placing an insulation layer could affect the temperature distribution within and around tunnels. Our results show that the temperature field without using an insulation layer is closer to the air temperature in the tunnel, and that the insulation layer has shielding effects and could plays an important role in preventing temperature migration to surrounding rocks. We further analyzed how thermal conductivity and thickness of insulation layer control the temperature distribution. The thermal conductivity and thickness of insulation layer only affect the temperature of the surrounding rocks which are located at distances below ~20 m from the lining.

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