A Study on the Heat Radiation of LED Luminaires and the Indoor Temperature Increase

The numerical simulation for radiant tube heat transferring process of the gas-infrared heated room was finished. By means of numerical calculation, the influences of radiant tube installation height to the indoor temperature and workspace air temperature as well as the heat radiation flux were studied. The results show: The greater of radiant tube surface installation height, The lower of the workspace average temperature, average radiation temperature and radiant tube total heat flux.

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Effect of Tree Shading on the Thermal Load of a House in a Warm Climate Zone in Mexico

Volume 7: Fluids and Heat Transfer, Parts A, B, C, and D ◽

10.1115/imece2012-87918 ◽

2012 ◽

Author(s):

M. A. Chagolla ◽

G. Alvarez ◽

E. Simá ◽

R. Tovar ◽

G. Huelsz

Keyword(s):

Temperature Increase ◽

Energy Savings ◽

Maximum Temperature ◽

Warm Climate ◽

Indoor Temperature ◽

Maximum Temperature Difference ◽

Energy Plus ◽

Test House ◽

Simulation Results ◽

North Latitude

This paper presents the effect of the shade of a tree on the indoor temperature and thermal loads of a house (test house) located in the State of Morelos, Mexico, 18° 50′ 43″ north latitude and 99° 10′ 44″ west longitude. Energy Plus was used to simulate different geometries of the shadow of a tree and the simulation results were compared with experimental measurements of the house without air-conditioning, for one warm and one cold week of the year 2011. The results showed that the maximum temperature difference between the measured and simulated temperatures with both geometry models of tree-shading was 1.7°C. When the effect of tree shading is not considered, it was found that there is a maximum temperature increase of 4°C in the warm week compared with the measured results. In the cold week, the temperature increase was 1.3°C compared with the measured results. Simulation results for an air-conditioned tree-shaded test house show that total annual energy consumption for cooling and heating to achieve thermal comfort represents a substantial energy savings of 76.6% when compared with an unshaded house.

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A Study on the Analysis of Pressure Difference According to the Stack Effect of High-Rise Buildings during Fire

Korean Society of Hazard Mitigation ◽

10.9798/kosham.2021.21.1.161 ◽

2021 ◽

Vol 21 (1) ◽

pp. 161-168

Author(s):

HyeWon Kim ◽

InHyuk Koo ◽

YunSeong Kim ◽

ByeongHeun Lee ◽

SeungHyeo Jin ◽

...

Keyword(s):

Temperature Change ◽

Pressure Difference ◽

Temperature Increase ◽

Growth Period ◽

Indoor Temperature ◽

Stack Effect ◽

High Rise

As the number of high-rise buildings in Korea continues to increase, interest in the stack effect is increasing. In particular, in the event of a fire, as the indoor temperature increases, there is the problem that the stack effect increases. Accordingly, it is necessary to analyze the stack effect resulting from temperature change during a fire. In this study, by using CONTAMW simulation, the opening was opened or closed. In the case where the temperature of the fire room rises to the temperature of the growth period caused by a fire, the pressure difference in the building according to the temperature increase during a fire was confirmed. As a result, depending on whether the opening was opened or closed, the pressure difference was uniform for each layer, ranging from 0 to 100 Pa when opened. However, assuming a fire room, the pressure in the fire layer increased to approximately 250 Pa, and it was confirmed that the pressure difference varied greatly for each floor.

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The Influence of an Integrated Driving on the Performance of Different Passive Heating and Cooling Methods for Buildings

Buildings ◽

10.3390/buildings9110224 ◽

2019 ◽

Vol 9 (11) ◽

pp. 224 ◽

Cited By ~ 1

Author(s):

Oropeza-Perez

Keyword(s):

Temperature Increase ◽

Temperature Drop ◽

Conventional Heating ◽

Passive Heating ◽

Indoor Temperature ◽

Pump System ◽

Heat Pump System ◽

Heating And Cooling ◽

Mobility Maintenance ◽

Cooling Methods

Passive cooling and heating methods within buildings are studied a lot nowadays. Nevertheless, their performance considering their driving has not been deeply studied. Therefore, the performance of the most common passive heating and cooling methods is analyzed in this document. The methods are divided into three categories: operable, semi-operable, and not operable. They are studied under different conditions of operation in order to estimate their performance in terms of indoor temperature increase/decrease in a single dwelling. The study is carried out with the thermal simulation program EnergyPlus, using a dwelling in Mexico City as a case study, which is validated with literature that studied passive methods for similar climates. Furthermore, for an integrated driving, four features of operation of the passive methods are considered: mobility, maintenance, assembly, and consumables. The results show that a correct use of these features of driving might achieve a significant temperature drop in the case of cooling and a significant indoor temperature increase in the case of heating. This is reflected in a considerable amount of energy saving compared to a conventional heating/cooling heat-pump system running under regular conditions, which is taken as a reference of consumption. Thereby, it is concluded that the proper usage, considered here as the correct application of the four features of operation mainly by the occupants, might have a high influence in their performance of increase/decrease of the indoor temperature. Thus, it is highly recommended to follow up their performance once installed and not to suppose an optimal performance ever after.

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Simulation Study on the Radiant Tube Transferring Characteristics for the Gas-Infrared Heated System

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.594-597.2086 ◽

2012 ◽

Vol 594-597 ◽

pp. 2086-2089

Author(s):

Da Ying Zhang ◽

Wei Dong Zhuang ◽

Ke Qin Gong

Keyword(s):

Numerical Simulation ◽

Heat Flux ◽

Numerical Calculation ◽

Radiation Flux ◽

Heat Radiation ◽

Total Heat Flux ◽

Tube Surface ◽

Indoor Temperature ◽

Radiant Tube ◽

Average Temperature

The numerical simulation for radiant tube heat transferring process of the gas-infrared heated room was finished. By means of numerical calculation, the influences of radiant tube emittance to the indoor temperature and workspace air temperature as well as the heat radiation flux were studied. The results show: The greater of radiant tube surface emittance, The higher of the total heat flux, meanwhile, workspace average temperature and average radiation temperature are rise.

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