Refrigeration systems with the night radiative cooling effect for different regimes and climatic conditions

2018 ◽  
Author(s):  
A. P. Tsoy ◽  
A. V. Baranenko ◽  
D. A. Tsoy
Keyword(s):  
Climatic Conditions ◽  
Cooling Effect ◽  
Radiative Cooling

Methane emissions reduce the radiative cooling effect of a subtropical estuarine mangrove wetland by half

2020 ◽  
Vol 26 (9) ◽  
pp. 4998-5016 ◽  
Author(s):  
Jiangong Liu ◽  
Yulun Zhou ◽  
Alex Valach ◽  
Robert Shortt ◽  
Kuno Kasak ◽  
...  
Keyword(s):  
Methane Emissions ◽  
Cooling Effect ◽  
Radiative Cooling ◽  
Mangrove Wetland

scholarly journals URBAN FOREST COMPONENTS INFLUENCING MICROCLIMATE AND COOLING POTENTIAL1

2017 ◽  
Vol 41 (6) ◽  
Author(s):  
Angeline Martini ◽  
Daniela Biondi ◽  
Antonio Carlos Batista
Keyword(s):  
Relative Humidity ◽  
Fixed Points ◽  
Strong Correlation ◽  
Urban Forest ◽  
Climatic Conditions ◽  
Tree Density ◽  
Cooling Effect ◽  
Different Types ◽  
Number Of Individuals

ABSTRACT Planting areas with arboreal vegetation has been proposed as a way to improve the climatic conditions of cities. However, it is not yet known which components of urban forest provide more satisfactory effects. The main goal of this study was to determine which components of the landscape provide greater influence on the microclimate and the cooling potential of the urban forest. For this, areas of different types of urban forest were selected. Using the fixed points method, the microclimate of the areas was analyzed, and by means of mobile transects walking a route of 500 m in an adjacent street, it was possible to analyze the influence in the immediate environment, determining the potential of cooling. The results indicated that the number of individuals and the tree density of the areas showed a statistically strong correlation with the temperature and relative humidity values, as well as with the cooling potential. In addition, it was found that 70% of the influence that the urban forest provides on the immediate surroundings can be explained by the number of trees. It is concluded that the number and density of individuals were the components of urban forest typologies that exerted greater influence on the microclimate, as well as on the cooling effect.

Thermal Radiative Cooling Enabled Freeze Tweezer for Manipulating Micro Scale Objects

2011 ◽  
Author(s):  
Yang Yang ◽  
Jing Liu
Keyword(s):  
Numerical Simulation ◽  
Small Volume ◽  
Freezing Behavior ◽  
Cooling Effect ◽  
Radiative Cooling ◽  
Convective Cooling ◽  
Micro Scale

A freeze tweezer is a new kind of manipulation tool which employs the freezing force of a small volume of nucleotide ice for operating the micro-objects in an aqueous state. Previously, such typical device prototypes were respectively realized based on conductive and convective cooling effect. Aiming to present an alternative feasible way for realizing the freeze tweezer in micro or even much smaller size by thermal radiative cooling, a complete 3-D numerical simulation on the operation behaviors of such kind freeze tweezer have been implemented. As a result, the droplet freezing behavior is directly caused by the freeze tweezer rather than the thermal radiative cooling from the sidewall. It indicates that this new freeze tweezer would also complete all the functions as its previous type would achieve.

Thermal Modeling of a Building Integrated Radiative Cooler for Space Cooling Applications

2018 ◽  
Author(s):  
Ravita Lamba ◽  
Mehdi Zeyghami ◽  
David Young ◽  
D. Yogi Goswami ◽  
S. C. Kaushik
Keyword(s):  
Heat Transfer ◽  
Energy Savings ◽  
Economic Value ◽  
Climatic Conditions ◽  
Radiative Cooling ◽  
Transfer Model ◽  
Ambient Conditions ◽  
Transfer Coefficients ◽  
Emissive Power ◽  
Recent Developments

Recent developments of plasmonic emitters that emit infra-red radiation in the range of 8–13 micron wavelengths that can be transmitted through the atmosphere have opened up the potential of cooling buildings passively by radiating heat through this atmospheric window into the deep space. This paper presents an analysis of the potential of this method to cool buildings radiatively 24 hours per day. Air conditioning units consume a large amount of electricity and are the main drivers of peak electricity loads. A transient thermal model of a building integrated radiative cooling (BIRC) system was carried out for passive radiative cooling of buildings. A MATLAB code was developed for solving the heat transfer model of the BIRC system using a numerical iterative approach. The effects of operating parameters such as cooling emissive power and ambient conditions on the performance of the system were studied. Furthermore, effects of non-radiative heat transfer processes were studied by considering different heat transfer coefficients. Based on this analysis, energy savings potential of radiative cooling of buildings was estimated for the climatic conditions of Miami, FL, and Chicago, IL, USA for a fraction of a roof surface covered with a radiative cooler. Further, the results of this analysis are in line with previous studies estimating the cooling potential of up to 100 W/m2 with radiative cooling systems. These results will help in estimating the economic value of cooling buildings by using plasmonic emitting surfaces on the building skins.

scholarly journals Numerical calculation of passenger compartment cooling effect under the action of radiative cooling film based on MATLAB

2021 ◽  
Vol 2125 (1) ◽  
pp. 012027
Author(s):  
Yipeng Chao ◽  
Xin Luo ◽  
Chao Zheng ◽  
Yipeng Chao
Keyword(s):  
Ambient Temperature ◽  
Infrared Radiation ◽  
Simulation Models ◽  
Cooling Effect ◽  
Radiative Cooling ◽  
Passenger Compartment ◽  
Time Space ◽  
Cold Source ◽  
Radiation Material ◽  
Atmospheric Transmittance

Abstract Radiative cooling uses space cold source to cool the object, and the radiative cooling film made by using this principle can be applied to automobiles effectively to save the refrigeration resources of automobiles. However, due to the limitation of economy, time, space and other factors, it is difficult to carry out comprehensive research on the actual film-forming cooling effect. Based on the principle of passive radiative cooling, a set of simulation models is developed, which is applied to the selection of infrared radiation materials for automotive radiative cooling film and the study of the influence of environmental factors on the radiative cooling effect. SiO2 was finally selected as infrared radiation material. At the same time, the theoretical cooling temperature of the radiative cooling film applied to the passenger compartment of automobiles can reach 6.8°C under the conditions of 35°C ambient temperature, 0.99 atmospheric transmittance and 10 heat transfer coefficient, using SiO2 as infrared radiation material and PE as dispersion substrate. At the same time, the cooling effect of the radiative cooling film is positively correlated with the ambient temperature, atmospheric transmittance to some extent.

scholarly journals Radiative cooling in polish climatic conditions

2018 ◽  
Vol 44 ◽  
pp. 00016
Author(s):  
Wojciech Cepiński ◽  
Bartosz Szmigiero
Keyword(s):  
Renewable Energy ◽  
Energy Demand ◽  
Energy Use ◽  
Cooling System ◽  
Climatic Conditions ◽  
Radiative Cooling ◽  
Energy Yield ◽  
The World ◽  
Building Cooling ◽  
Reducing Energy

Ecological, natural ways of obtaining energy for building cooling are becoming more and more popular around the world. Reducing energy demand and increasing the renewable energy use can be achieved for example by using radiative cooling. Depending on climatic conditions and the type of cooling system, radiative cooling is able to cover a part of refrigeration needs. The document presents the possible energy yield from using radiative cooling in systems operating at respective parameters in polish climatic conditions.

scholarly journals Estimation of multi-layer coating efficiency for passive radiative cooling

2021 ◽  
Vol 5 (2) ◽  
pp. 37-46
Author(s):  
S. S. Jenblat ◽  
◽  
O. V. Volkova ◽  
Keyword(s):  
Mathematical Model ◽  
Optical Properties ◽  
Cooling System ◽  
Climatic Conditions ◽  
Cooling Power ◽  
Radiative Cooling ◽  
Cooling Systems ◽  
Coating Efficiency ◽  
Atmospheric Transmittance ◽  
Layer Coating

Passive radiative cooling is a promising direction in energy conservation and environmental protection. One of the ways to increase the efficiency of radiative cooling systems is the use of multi-layer coatings. In recent years, several novel materials with high emissivity have been proposed, which allow the creation of radiators that provide an average daily cooling power of approximately 100 W/m2 during daytime. Based on the developed mathematical model, the optical properties of the multi-layer coating for the radiative cooling system were evaluated by the Transfer Matrix Method and the effectiveness of radiative cooling was determined due to the use of the multi-layer coating in the climatic conditions of Syria (Latakia). The results of modeling the atmospheric transmittance in the summer months in Syria (Latakia) are presented. The developed mathematical model, methods for modeling atmospheric transmittance, calculating solar radiation, and evaluating the optical properties of multi-layer coating, allow determining an effective multi-layer coating for radiative cooling systems in any climatic conditions

Sign in / Sign up

Export Citation Format

Share Document