Impact of Locally Available Thermal Insulation Structures on Space Heating Demand of High-altitude Rural Buildings: A Case Study of Kyrgyzstan

This paper presents possible variants of reducing the heat loss in an existing heating network made from single pre-insulated pipes located in central Europe. In order to achieve this aim, simulations were carried out for five different variants related to the modification of the network operation temperature, replacement of a single network with a double pre-insulated one, and changes in the cross-section geometry of the thermal insulation of the double heating network from circular to egg-shaped. The proposed egg-shaped thermal insulation was obtained by modifying the shape of the Cassini oval, in that the supply pipe has a greater insulation thickness compared to the return pipe. The larger insulation field in the supply pipe contributed to reducing the heat flux density around the supply line and, as a result, to significantly reducing heat loss. The egg-shaped thermal insulation described in the publication in a mathematical formula can be used in practice. This work compares the heat losses for the presented variants and determines the ecological effect. Heat losses were determined using the boundary element method (BEM), using a proprietary computer program written as part of the VIPSKILLS 2016-1-PL01-KA203-026152 project Erasmus+.

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Himalayan Hotspot with Alien Weeds: A Case Study of Biological Spectrum, Phenology, and Diversity of Weedy Plants of High Altitude Mountains in District Kupwara of J&K Himalaya, India

Proceedings of the National Academy of Sciences India Section B Biological Sciences ◽

10.1007/s40011-020-01219-6 ◽

2021 ◽

Author(s):

Shiekh Marifatul Haq ◽

Maroof Hamid ◽

Fayaz A. Lone ◽

Bikarma Singh

Keyword(s):

High Altitude ◽

Biological Spectrum

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Influence of EPS, mineral wool and plaster layers on sound and thermal insulation of a wall: a case study

Applied Acoustics ◽

10.1016/j.apacoust.2018.03.001 ◽

2018 ◽

Vol 137 ◽

pp. 62-68 ◽

Cited By ~ 11

Author(s):

Kestutis Miskinis ◽

Vidmantas Dikavicius ◽

Andrius Buska ◽

Karolis Banionis

Keyword(s):

Thermal Insulation ◽

Mineral Wool

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Analysis of the sensitivity of the ecological effects for the investment based on the thermal insulation of the building: A Polish case study

Journal of Cleaner Production ◽

10.1016/j.jclepro.2017.06.123 ◽

2017 ◽

Vol 162 ◽

pp. 856-864 ◽

Cited By ~ 2

Author(s):

Janusz Adamczyk ◽

Robert Dylewski

Keyword(s):

Thermal Insulation ◽

Ecological Effects

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Evaluation of a radiation-based empirical model for estimating hourly reference evapotranspiration for high-altitude climatic conditions: A case study for the state of California

Journal of Earth System Science ◽

10.1007/s12040-019-1096-7 ◽

2019 ◽

Vol 128 (4) ◽

Cited By ~ 1

Author(s):

Chatzithomas D Constantinos

Keyword(s):

High Altitude ◽

Empirical Model ◽

Reference Evapotranspiration ◽

Climatic Conditions ◽

The State

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

Advances in Civil Engineering ◽

10.1155/2019/4978359 ◽

2019 ◽

Vol 2019 ◽

pp. 1-14 ◽

Cited By ~ 1

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.

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Influence of Altitude on the Performance of a Bicycle-Cyclist Set

Volume 3: 19th International Conference on Advanced Vehicle Technologies; 14th International Conference on Design Education; 10th Frontiers in Biomedical Devices ◽

10.1115/detc2017-67955 ◽

2017 ◽

Author(s):

Mateo Morales ◽

Sergio D. Roa ◽

Luis E. Muñoz ◽

Diego A. Ferreira ◽

Omar D. Lopez Mejia

Keyword(s):

High Altitude ◽

Drag Force ◽

Power Output ◽

Aerodynamic Drag ◽

Integrated Approach ◽

Cycling Performance ◽

Air Density ◽

Effort Tests ◽

Different Altitudes

There is a tradeoff between power delivery and aerodynamic drag force when cyclists ride at different altitudes. The result is particular to the characteristics of the bicycle as well as the aerobic fitness of the cyclist. This work proposes a methodology based on an integrated approach to the study of the influence of altitude on power output and aerodynamic drag over a particular bicycle-cyclist set. The methodology consists of an independent analysis for each of the effects, to conclude with an integration of results that allows estimating the overall effect of altitude on cycling performance. A case study for the application of the methodology was developed, and the obtained results apply for the specific bicycle-cyclist set under analysis. First, the relationship between power and time was analyzed for a male recreational cyclist based on all-out effort tests at two different altitudes: 237 meters and 2652 meters above sea level (m.a.s.l). Second, the effects of environmental conditions on air density and drag area coefficient due to altitude changes were analyzed based on Computational Fluid Dynamics (CFD) simulations. It was found that for the bicycle-cyclist set under study, the sustainable power output for 1-hour cycling was reduced 45W for the high-altitude condition as a consequence of the reduction in the maximum oxygen uptake capacity. In addition, the aerodynamic drag force is reduced in greater proportion due to the change in air density than due to the change in drag coefficient. Finally, the results of both effects were integrated to analyze the overall influence of altitude on cycling performance. It was found that for the analyzed case study, the aerodynamic advantage at higher altitude dominates over the disadvantage of reduction in power output: despite delivering 45W less, the subject can travel an additional distance of 900 meters during a one hour ride for the high-altitude condition compared to that in low altitude.

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