scholarly journals Research on Energy-Saving Design of Rural Building Wall in Qinba Mountains Based on Uniform Radiation Field

2020 ◽  
Vol 2020 ◽  
pp. 1-16
Author(s):  
Qin Zhao ◽  
Xiaona Fan ◽  
Qing Wang ◽  
Guochen Sang ◽  
Yiyun Zhu
Keyword(s):  
Heat Transfer ◽  
Heat Transfer Coefficient ◽  
Energy Consumption ◽  
Transfer Coefficient ◽  
Energy Saving ◽  
Radiation Field ◽  
Thermal Environment ◽  
Residential Buildings ◽  
South Wall ◽  
Heating Energy Consumption

How to create a healthy and comfortable indoor environment without causing a substantial increase in energy consumption has become a strategic problem that the development of all countries must face and solve. According to the climatic conditions of Qinba Mountains in China, combined with the characteristics of local rural residential buildings and residents’ living habits, the field survey and theoretical analysis were used to study the thermal environment status and the heating energy consumption condition of local rural residential buildings. The thermal design method of walls for the local rural energy-saving buildings based on the indoor uniform radiation field was explored by using the outdoor comprehensive temperature function expressed by the fourth-order harmonic Fourier series as the boundary condition of the wall thermal analysis. ANSYS CFX was adopted to study the suitability of the energy-saving wall structure designed by the above method. The results show that the indoor thermal environment of local rural residential buildings in winter is not ideal and the heating energy consumption is high, but this area has the geographical advantage to develop solar energy buildings. It is proposed that the indoor thermal comfort temperature of local rural residential buildings in winter should not be lower than 14°C. When the internal surface temperature of the external walls in different orientations are equally based on the design principle of uniform radiation field, the heat transfer coefficient of the east wall, the west wall, and the north wall of the local rural residential buildings is 1.13 times, 1.06 times, and 1.14 times of the south wall heat transfer coefficient, respectively. The energy-saving structural wall with KPI porous brick as the main material and the south wall heat transfer coefficient of 0.9 W/(m2·K) is the most suitable energy-saving wall for local rural residential buildings.

scholarly journals Indoor environmental assessment method in residential kitchen

2020 ◽  
Vol 24 (3 Part B) ◽  
pp. 2055-2065
Author(s):  
Anita Vorosne-Leitner ◽  
Laszlo Kajtar ◽  
Jozsef Nyers
Keyword(s):  
Heat Transfer ◽  
Heat Transfer Coefficient ◽  
Energy Consumption ◽  
Transfer Coefficient ◽  
Residential Buildings ◽  
Local Source ◽  
Radiant Heat Transfer ◽  
Main Role ◽  
Monitoring Method ◽  
Gas Stoves

Nowadays, energy consumption, environmental protection and safety are fundamental issues in design process. In order to reduce energy consumption, buildings become increasingly insulated and air tight. It has controversial effect on indoor environment, therefore, it has become essential to apply an effective ventilation system. This requires detailed design, especially if there is a strong, local source in the space. In residential buildings, gas stoves are significant source of gaseous pollutants and heat load. Indoor environmental assessments have been carried out in order to evaluate the key parameters. The aim of this studies is to develop a new design and monitoring method of residential kitchens with gas stoves. Primary results of laboratory researches indicate that the largest stovetop burner with power of 2.8 kW, has the main role. Significant emissions of NOx have been measured, in an average size kitchen (Vroom = 36 m3) the Hungarian standard NOx concentration level (200 ?g/m3) can be ensured with an exhaust air-flow of 1102 m3/h. With respect of thermal environmental parameters, heat loads of residential gas stoves could be characterized with convective heat transfer coefficient of 4.5 W/m2K and radiant heat transfer coefficient of 5.9 W/m2K. As regards thermal comfort parameters, predicted mean rate index in proved to be applicable in residential kitchens from ?0.3 to +2.0. However draught rating cannot be applied, with respect to the temperature limitations.

scholarly journals The Influence of Window-Wall Ratio on Heating Energy Consumption of Rural House in Severe Cold Regions of China

2020 ◽  
Vol 173 ◽  
pp. 03008
Author(s):  
Teng Shao ◽  
Hong Jin ◽  
Wuxing Zheng ◽  
Jin Wang
Keyword(s):  
Heat Transfer ◽  
Heat Transfer Coefficient ◽  
Energy Consumption ◽  
Transfer Coefficient ◽  
Thermal Performance ◽  
Outdoor Environment ◽  
Shape Coefficient ◽  
Heating Energy Consumption ◽  
The Heat Transfer Coefficient ◽  
Large Shape

Rural houses in severe cold areas of China are mostly single-storey independent buildings with large shape coefficient. Compared with urban residential, it has larger contact area between envelope and outdoor environment of each household. Meanwhile, the heat transfer coefficient of window is usually greater than that of external wall and roof. The window-wall ratio is one of the important indicators affecting the energy consumption of rural house. This paper takes window-wall ratio as the main variable, building orientation, thermal performance of envelope and window heat transfer coefficient as the auxiliary variables, and applies DesignBuilder software to quantitatively analyse the mechanism of window-wall ratio on rural house’s heating energy consumption under the interactive influence of multiple factors. Results show that the influence rule of window-wall ratio with different orientations on heating energy consumption will change when the thermal performance of envelope or window heat transfer coefficient changed. The synthetic effect of various factors should be considered in the design to reasonably determine the windowwall ratio of rural house.

scholarly journals The effect of different types of window for residential building based on intermittent heating supply

2019 ◽  
Vol 136 ◽  
pp. 03020
Author(s):  
Chenyang Tao ◽  
Nan Li ◽  
Yuchen Wang
Keyword(s):  
Heat Transfer ◽  
Heat Transfer Coefficient ◽  
Energy Consumption ◽  
Transfer Coefficient ◽  
Residential Buildings ◽  
Recovery Period ◽  
Residential Building ◽  
Thermal Design ◽  
Intermittent Heating ◽  
Different Types

Aiming to lessen energy consumption and heating cost, this paper analyzes the effect of different types of window for residential building based on intermittent heating supply. The research results show that the type of window with a smaller heat transfer coefficient has higher energy consumption. Otherwise, the rate of temperature rising is slightly affected by the change of window with different heat transfer coefficient and window-to-wall ratio. Based on the economic and technical analysis, through changing the better window, energy-saving ratio can be arrived to 10.4%-16.8% and economic recovery period is 4.4-10.4 years. The research findings can be used for reference to thermal design in new residential buildings and provide improvement of building performance for existing residential buildings.

Determination of the Effect of Wall Heating Systems on Convective Heat Transfer Coefficient in Buildings

2014 ◽  
Vol 875-877 ◽  
pp. 1630-1636 ◽  
Author(s):  
Ozgen Acikgoz ◽  
Olcay Kincay ◽  
Zafer Utlu
Keyword(s):  
Heat Transfer ◽  
Heat Transfer Coefficient ◽  
Energy Consumption ◽  
Thermal Comfort ◽  
Transfer Coefficient ◽  
Convective Heat Transfer ◽  
Convective Heat ◽  
Convective Heat Transfer Coefficient ◽  
Heated Wall ◽  
Real Size

Decreasing energy consumption and advancing thermal comfort are the most important aims of building engineering. Previously reported studies by many researchers have found that different usages of convective heat transfer coefficient (CHTC) correlations in heating system simulations have considerable impacts on calculated heating load in buildings. Hence, correct utilization of CHTCs in real size room enclosures has great importance for both energy consumption and thermal comfort. In this study, a modeled room was numerically heated from one vertical wall and cooled from the opposite wall in order to create a real room simulation. While cooled wall simulate heat losses of the room, heated wall simulates the heat source of enclosure. Effects of heated and cooled wall temperatures and characteristic length on CHTC and Nusselt number in the enclosure were numerically investigated for two (2-D) and three dimensional (3-D) modeling states. CHTCs and Nusselt numbers of a real size room with the dimensions of 6.00 by 2.85 by 6.00 were found with FLUENT CFD and graphics of change were drawn. As result, difference between 2-D and 3-D solutions was found approximately 10%. This was attributed as the effect of air flow pattern effects over other surfaces in the enclosure that can not be counted at 2-D solutions. The change of CHTC at different characteristic lengths was illustrated as well.

scholarly journals A New Energy-Efficient Building System Based on Insulated Concrete Perforated Brick with a Sandwich

2018 ◽  
Vol 4 (7) ◽  
pp. 1467 ◽  
Author(s):  
Guoqi Xing ◽  
Jing-jie Yu ◽  
Chun-gang Zhang ◽  
Jun-xi Wu
Keyword(s):  
Heat Transfer ◽  
Heat Transfer Coefficient ◽  
Transfer Coefficient ◽  
Energy Saving ◽  
Energy Efficient ◽  
Field Tests ◽  
Insulating Layer ◽  
New Energy ◽  
Building System ◽  
Energy Efficient Building

The purpose of this research is to put forward a new energy-efficient building system that can meet the energy saving requirement of 65% for public buildings in cold areas based on modified insulated concrete perforated brick with a sandwich. Modified brick was composed of three parts and three parts can be made a whole in brick manufacturing and it was called self-thermal insulation concrete perforated brick and could avoid appearance of cracks. The tesst was done to obtain thickness of EPS for modified insulated concrete perforated brick with a sandwich in order to meet the requirement of insulation. Thickness of EPS was set to to 45, 50, 55, 60, 65 and 75 mm respectively and comparative experiments were also carried out to verify the effect of insulation for modified bricks and unmodified bricks. Field tests were carried out to obtain appropriate masonry methods for modified bricks. Based on the results of analysis and discussion, then obtained: (1) Heat transfer coefficient of wall made by modified bricks was less than heat transfer coefficient of wall made by unmodified bricks when the same for thickness of EPS, it could be reduce by up to 45%; (2) When thickness of insulating layer was 65 mm, heat transfer coefficient of wall made by modified bricks could reached minimum limit 0.45 and it could meet energy saving requirement of 65% for buildings in cold area. (3) Insulating layer, located inside of the wall, could avoid appearance of cracks on surface of wall for modified bricks.

Study on Energy-Saving Renovation of Existing Heating Masonry-Concrete Residential Buildings

2011 ◽  
Vol 280 ◽  
pp. 147-151 ◽  
Author(s):  
Hong Guo ◽  
Min Fang Su ◽  
Xiao Jun Jin
Keyword(s):  
Energy Efficiency ◽  
Energy Consumption ◽  
Energy Saving ◽  
Thermal Environment ◽  
Residential Buildings ◽  
Residential Building ◽  
Building Envelope ◽  
Indoor Thermal Environment ◽  
Consumption Situation ◽  
Current Energy

Based on the current energy consumption situation of existing masonry-concrete residential buildings in China, it discussed the main energy-saving renovation policies and technologies. Taking existing masonry-concrete residential building of Taiyuan city as a case, it analyzed its heat loss situations, energy-saving renovation design and reconstruction technologies of building envelope. It discussed energy-saving renovation effects. Energy efficiency and indoor thermal environment improved significantly after energy-saving renovation. The building life is extended.

Numerical Simulation of a Canadian Well With Several Circumferential Rows of Internal Vortex Generators

2021 ◽  
Author(s):  
Nabil Kharoua ◽  
Hamza Semmari ◽  
Houssem Korichi ◽  
Mehdi Haroun
Keyword(s):  
Heat Transfer ◽  
Reynolds Number ◽  
Heat Transfer Coefficient ◽  
Transfer Coefficient ◽  
Residential Buildings ◽  
Vortex Generators ◽  
Ambient Conditions ◽  
Operational Conditions ◽  
Positive Effects ◽  
The Heat Transfer Coefficient

Abstract Canadian Wells exploit the quasi-stable underground temperature throughout the year for cooling and heating applications. This type of heat exchangers is used in residential buildings, agriculture and industry. Implementing Vortex Generators (VGs) is intended to disturb the thermal and dynamic boundary layers developing in the near-wall regions leading to the increase of the heat transfer coefficient. The present work investigates the positive effects of a sequence of several rows of VGs. The commercial code ANSYS FLUENT was used to perform numerical simulations mimicking the variation of the seasonal operational conditions occurring within one year. The ambient conditions were considered for the city of Constantine located in the east of Algeria at an altitude of 600m over the sea level. Sinusoidal functions of time and depth, were used for the yearly variations of the ground and air temperatures. Parallelepiped VGs were considered in this study. The Reynolds number was in the range Re = 14975–42789. The results illustrated a contrasting effect of the Reynolds number on the heat transfer coefficient and the temperature difference between the inlet and outlet of the Canadian Well. In terms of number of VGs rows, the beneficial heat transfer effects were observed till the fifth row only.

Performance Experimental Study and Energy Consumption Calculation of Hollow Glass Window Film

2011 ◽  
Vol 250-253 ◽  
pp. 356-359
Author(s):  
Dan Ping Yang ◽  
Jia Peng He ◽  
Zheng Song Zhang
Keyword(s):  
Heat Transfer ◽  
Experimental Study ◽  
Heat Transfer Coefficient ◽  
Energy Consumption ◽  
Transfer Coefficient ◽  
Window Glass ◽  
Hollow Glass ◽  
Window Film ◽  
The Heat Transfer Coefficient ◽  
Energy Consumption Calculation

This paper taked hollow glass window as the model, and heat transfer coefficient, sunshading coefficient and energy consumption of the window glass were obtained in the situations of window glass with and without low-E film by doing experiment and theoretical calculation. The results show that both heat transfer coefficient and sunshading coefficient decrease comparing the hollow glass window film with no film. For the fixed and push-pull window of the whole window, the heat transfer coefficient decrease by 24.2% and 28.9% respectively and sunshade coefficient decreases by 31.37%. And the low-E film by this study adopting reduces energy consumption of the summer greatly by 32.96%, and has no too large effect on winter heating, so the annual energy consumption reduces and the window film saves annual energy consumption 14.62% .

Sign in / Sign up

Export Citation Format

Share Document