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Maintaining the human body temperature is one among the foremost basic desires for living, which regularly consumes an enormous quantity to stay the ambient temperature constant. Our overall health is often reliant upon temperature in many ways additionally. In this project the issues on maintaining the temperature in a convenient way is considered mainly demanding new effective ways to manage it. Particularly, textile-based personal thermal management has huge potential as a result of it focuses the temperature management close to the human body rather than the entire building not like regular thermostat. The main project objective is that the fabric will auto detects the patient’s temperature and generate heat on one side and generate chillness on the other hence can be used as a dual-purpose blanket. The blanket generally works with medium density polyethylene with copper and carbon relative to the emissivity. The carbon coated layer is on the outside when the person or a patient is trying to cool down and the heat radiates out producing a cooling effect with the high and low range of the emissivity. When the person or a patient needs heat, the blanket can be turned inside out and the copper coated layer keeps the heat by creating an insulating effect and warms up the patient instant. The thermal emissivity of the chosen compound for developing a dual mode blanket has been demonstrated using COMSOL Multiphysics (5.6) software and the blink monitoring app is developed for the purpose of monitor the body temperature continuously.

The depletion of fossil fuels has led to the rapid development of environmentally friendly lithium ion battery (LIB). However, exposure of LIB to elevated temperatures frequently leads to battery failure, thermal runaway (TR), or even TR propagation. In this study, a series of experiments are conducted on the LIBs with and without water mist at different initial temperatures (50°C and 106-206°C) in a novel designed battery module to investigate the cooling effect of water mist. The results show that water mist reduces the possibility of battery failure and inhibits TR. The critical temperature of TR is enhanced by 36°C. Moreover, using water mist to suppress the TR propagation requires reducing the temperature of a cell that undergoing TR to below 126°C. Analysis of cooling rate indicates that there are four cooling modes ((Ⅰ) rapid cooling and quasi-steady state, (Ⅱ) rapid cooling and slow cooling, (Ⅲ) transitional stage, and (Ⅳ) rapid heating and rapid cooling) of water mist. The heat absorbed by water mist is distinct in four cooling modes. These results reveal that water mist has better cooling effect and the cooling mode changes with the increase of temperature, which may provide insight into the thermal safety performance of cells.

We compare prices of financial derivatives whose payouts are based on future weather outcomes to CMIP5 climate model predictions as well as observed weather station data across eight cities in the US from 2001 through 2020. Derivative prices respond both to short-term weather forecasts for the next two weeks and longer-term warming trends. We show that the long-term trends in derivative prices are comparable to station-level data and climate model output. The one exception is February in the northeastern US, where financial markets price in a polar vortex-induced cooling effect, a recent scientific finding that was not present in the older CMIP5 climate output. When looking at the spatial and temporal heterogeneity in trends, futures prices are more aligned with climate model output than observed weather station trends, suggesting that market participants closely align their expectations with scientific projections rather than recent observations.

A method of using condensate water to reduce the airflow temperature around the air conditioner condenser and improve the performance of air conditioner is presented in this study. The structure of traditional split air conditioner is adjusted by changing the installation direction of fan and adding disk-type atomization cooling element (ACE) in the outdoor unit. The performance of the air conditioner under four modes is tested in different environment temperatures. Four modes were named, i.e. the original unit without ACE, original unit with ACE, blowing mode without condensate water and blowing mode with condensate water. The blowing mode with condensate water is used to pre-cool the incoming airflow, and the maximum temperature reduction at the air outlet surface of the condenser is up to 2.2 °C in 35 °C. With the environment temperature increasing, the refrigerating capacity of four modes decreased, and the power consumption increased, leading to the decrease of EER. However, owing to the cooling effect of condensate water, the performance of blowing mode with condensate water was greatly improved compared with the original unit without ACE. The variation rates of refrigerating capacity, power consumption and EER at environment temperature of 43 °C were 8.1%, -9.5% and 20%, respectively. The unit with condensate water could greatly improve the performance of air conditioning in high environment temperatures.

Batch homogeneity during lyophilization is crucial to ensure products with high quality. Known as edge-vial-effect, vials at the corners and edges tend to run warmer than center vials during primary drying. This is associated with risk of collapse or increased costs due to use of more conservative, longer drying conditions resulting in lower product temperature. The edge-vial-effect has been attributed to radiation coming from the chamber wall. We could show that the neighbor vial has a dominant impact on product temperature during lyophilization. Depending on the number of neighbors as well as the distance to a neighbor vial, the neighbor vial exerts a remarkable cooling effect. Energy transfer by gas conduction enables the cooling effect of a neighboring vial over a distance up to 10 mm. This not only leads to prolonged primary drying but also impacts cake appearance. Thus, to avoid trouble during lyophilization you have to watch out for the neighborhood.

Proper ventilation in dairy barns is important in the summer as high temperatures and the accompanying heat stress can affect the health of the livestock. Although, high speed fans have been in use for a long time to cater to the needs of cooling, HVLS (High Volume Low Speed) fans have proved to be worthy of attention. The cooling effect of the large diameter HVLS fans were compared with that of high speed conventional drum fans in a simulated space using CFD models of the setups at their respective high rotational speeds. This particular work employs MRF (Moving Reference Frame) technique within the CFD simulation. The performance of both these setups were analysed at different heights and distances in order to meticulously compare the performance of the two setups more accurately. The air velocities from the HVLS fans were only slightly less than the high speed drum fans at a distance of 1 m while at increasing distances, the HVLS fan remained more effective than the high speed fans. Also, the HVLS fans covers larger area with more uniform airflow than the high speed fans.

Despite the common use of cutting fluids in metal cutting, most simulations of these processes only consider dry conditions. This is largely due to limitations in conventional simulation methods, such as the Finite Element Method (FEM), regarding fast changing computational domains. In this paper, a simulation model of metal cutting with cutting fluid based on the Finite Pointset Method (FPM) is presented. This approach allows to simulate the Fluid-Structure-Interactions (FSI) within the same simulation method. For different orthogonal turning processes, the simulations are compared with experiments for dry and wet conditions. The simulation results illustrate the cooling effect numerically.

Background Burn wound progression is a significant problem as burns initially thought to be superficial can actually become full thickness over time. Cooling is an efficient method to reduce burn wound conversion. However, if the cooling agent is below room temperature, depending on the wound size the patient is at risk of hypothermia. Additionally, tissue perfusion is reduced leading to an aggravation of burn wound progression. We investigated if wound dressings based on non-pre-cooled bacterial nanocellulose (BNC) with a high water content cool a burn just by evaporation and reduce the intradermal damages in the skin. Material and methods In a human ex-vivo model, skin explants underwent contact burns using a 100 °C hot steel block. The burned areas were divided into two groups of which one was cooled with a BNC-based wound dressing. Intradermal temperature probes measured temperature in cooled and uncooled burn sites over 24 h. For histological assessments of the burned areas biopsies were taken at different time points. High mobility group box-1 (HMBG1) staining served as marker for cell vitality and necrosis in the different skin layers. Results Intradermal temperature measurement showed that application of the BNC-based wound dressing reduced temperature significantly in burned skin. This cooling effect resulted in a maximum temperature difference of 6.4 ± 1.9 °C and a significant mean reduction of the area under the curve in the first hour after burn of 62% (p Conclusion Based on our results, BNC-based wound dressings cool a burn. Intradermal temperature as well as thermal damage of the tissue was reduced. The tested BNC-based wound dressing can be used without pre-cooling to cool a burn as well as to reduce the burn BNC-based wound progression through its evaporation cooling effect.

Water and energy supply are two of the key issues human beings must address to attain sustainable development. Humidification-dehumidification technology has been proven to be a cost-effective approach to fulfill the freshwater demand. Particular attention has been given to coupling the humidification-dehumidification cycles with refrigeration, power and other desalination technologies with the aim of enhancing the performance of the combined cycle as well as increasing the amount of produced freshwater, cooling effect, power, etc. This paper provides a comprehensive review of the state-of-the-art investigations in terms of humidification-dehumidification technologies and their integration with the aforementioned cycles. In other words, an attempt has been made to categorize and discuss the various combined cycles based on humidification-dehumidification technology. A detailed comparison has been drawn regarding the performance criteria of the coupled cycles in terms of freshwater production, gained output ratio, and cost per liter. This comprehensive review lays the groundwork for future research concentrating on humidification-dehumidification based energy cycles.

Water mist has a good three-dimensional cooling effect; however, its extinguishing effect on oil fires is less than that of foam extinguishing agents. This study aimed to enhance the gasoline fire extinguishing efficiency of water mist by adding KBr, Tween-80, and a dissolved CO2 solution as multicomponent additives with different suppression mechanisms. The fire extinguishing time was measured to evaluate the extinguishing efficiency of different additives. The test showed that KBr mainly works near the flame base and makes an unstable gap between the flame base and the gasoline surface; the Tween-80 mist and dissolved CO2 mist make the flame height lower under the test conditions. By analyzing the different extinguishing phenomena, temperature and efficiency of each additive, the multicomponent additives were proposed to enhance the extinguishing efficiency based on different mechanisms. The results showed the water mist with KBr, Tween-80 and dissolved CO2 resulted in a remarkable improvement in the ability to extinguish a gasoline fire compared with pure water mist.

TiO2 and ZnO based white paints are used worldwide to keep the buildings cool by reflecting solar heat flux. However, the cooling effect and lifetime of such coatings are limited by their band gap and fair reflectivity. Herein, scale-up synthesis of pure hexagonal ZnTiO3 pigment with an optical band gap of 3.75 eV is developed. It is found that the solar absorptance of the as-grown ZnTiO3 pigment is only 0.115, which is 0.038 and 0.044 lower in relation to the conventional ZnO and TiO2 pigments, respectively. Furthermore, the actual outdoor roof cooling test was performed at noon on a sunny day in summer. Interestingly, results found that while the ZnO white paint can decrease the roof temperature from 70.1 °C to 59.8 °C, the ZnTiO3 paint cools the roof from 70.1 °C to 55.2 °C. Compared to the 10.3 °C roof cooling effect of ZnO paint, the as-fabricated ZnTiO3 paint has a roof cooling effect as high as 14.9 °C, which is much more attractive for energy saving applications.

In order to improve the understanding of the burning behavior for the in-situ burning of the spilled crude oil on water, the influence of the oil pool diameter and oil layer thickness of pool fire on open water were studied in relation to the flame height, boilover, and burning efficiency. A series of experiments were conducted in a specially designed experimental setup which could simulate the boundary conditions of the actual ISB operation on water. Three quartz tubes with different diameters and three initial oil layer thicknesses were set as the initial conditions in this study. The results showed that the burning process of oil pool fire on open water could be divided into four stages which are growth stage, quasi-steady stage, decay stage and extinguishing stage. The average flame height of quasi-steady stage increased with oil pool diameter but was little influenced by the initial oil layer thickness. Boilover phenomena were observed in the experiment processes when the oil pool diameter was 150 mm, which showed much later boilover onset time, longer boilover duration and higher average flame height than that for the same size oil paool fire in steel vessel with water sublayer. The burning efficiencies increased with the initial oil layer thicknesses for a given oil pool diameter, which could be explained as the thermal insulation of oil layer. All of the burning efficiencies on experimental dimensions are below 65%, owing to the significant cooling effect of the large amount of water surrounding the burning system.

The urban environment, linked with human health, is a complex system disturbed by the roughness of the urban surface, unusually marked by buildings and greenbelts. The cooling effect of greenbelts inevitably responds to the distance from their locations to buildings and their characteristics, while the buildings are hardly independent of the greenbelts in terms of heat effects. To determine the role of building and greenbelt characteristics in mitigating heat stress, our study selected 3 greenbelts and 6 buildings in Beijing, China, and classified them into 2 clusters to compare the difference in monitored outdoor air temperatures (ATs) within two different building characteristics - height and length. One-way analysis of variance (ANOVA) and the least significant difference (LSD) were then employed to further test for significant difference. Our study indicates that each of the two characteristics (height and length) can bring about a significant hindering impact on greenbelt cooling effects. A greater building height or length has a greater hindering force to air (heat) flow. Knowing one or more of the characteristics of greenbelts or buildings is very critical to the improvement of the urban heat environment. Our study proposes an effective and practical outcome for facilitating governmental policy-making and planners' actions.

Crushed rock embankments are widely applied in the Qinghai–Tibet Railway. Most of previous studies have focused on the short-term cooling performance of crushed rock embankments, but few studies have concerned about the long-term cooling effect to ensure its service performance though monitored data. The long-term cooling effects of the U-shaped crushed rock embankment (UCRE), closed-system crushed rock-based embankment (CCRBE) and open-system crushed rock-based embankment (OCRBE) were evaluated based on 13-year monitored data at the Beiluhe experimental section. Compared with the conventional roadbed, the average ground temperature in 2017 at depths of 2, 5, and 10 m with the UCRE was decreased by 2.20 °C, 1.60 °C, and 0.94 °C, respectively. In the OCRBE, the mean annual temperature at the same depths dropped by 1.67 °C, 1.26 °C, and 0.80 °C, respectively. The mean annual temperature with the CCRBE dropped by 1.20 °C, 0.79 °C, and 0.45 °C, respectively. Therefore, the UCRE has the best long-term effect to decrease the temperature of underlying permafrost. Otherwise, crushed rock embankments existed as a staged cooling process. Engineering activities decreased temperature of underlying permafrost in short-term, but climate warming had a negative impact on the long-term cooling effect

Studies on the role of urban green spaces (UGS) in mitigating the urban heat island (UHI) effect demonstrate the influence of two related, but distinct attributes of UGS: the composition (amount), and configuration (spatial attributes and distribution) of UGS patches. While the positive role of UGS amount in providing cooling effect seems unequivocal, it is still not possible to develop a consensus on the role of UGS configuration from the small number of studies that have been conducted to-date. The latter observation could be due to different methodologies, such as choice of landscape metrics and statistical methods used in different studies, as well as differences in urban form of cities. This study addresses the current knowledge gap by using a same set of methodologies applied to four cities of different urban forms: Singapore and Hong Kong as compact cities, and Jakarta, Kuala Lumpur as sprawling cities. Landsat imageries were used to derive land cover and land surface temperature (LST) maps. Different statistical and spatial analysis techniques were also used. We report several novel findings from this study: (1) only four metrics of percentage of landscape (PLAND), area-weighted mean shape index (SHAPE_AM), patch density (PD), and mean Euclidean nearest neighbor distance (ENN_MN) were adequate to explain UGS pattern-LST relationships in all four cities; (2) the relative importance of composition versus configuration of UGS in determining LST seems to be a function of the existing UGS pattern: what the average per unit area of the city is like in terms of patch size (area-weighted mean patch size (AREA_AM)), shape complexity (SHAPE_AM), and distribution (skewness and kurtosis) of patches; and (3) decision tree classifier is a novel and effective method to unravel hidden patterns in complex UGS pattern-LST relationships. Our results also provide insights on UGS management in cities for higher cooling effects. Greening priorities may differ among cities. In cities where configuration is not a determinant of LST (e.g. Kuala Lumpur and Hong Kong), greening may focus on providing conditions necessary for configuration to influence LST and adding greenery, and where configuration already affects LST (e.g. Jakarta and Singapore), the focus may be placed on optimization of UGS by providing larger, simpler in shape, more aggregated and connected, and less fragmented UGS patches.

An experimental investigation was carried out to analyze the film cooling performance over a fiber-reinforced composite plate with anisotropic thermal conductivity (ATC). The influence of the ATC and its spatial variations on the cooling effect under different blowing ratios was studied. It was found that the heat transfer in the plate was enhanced in the direction with higher thermal conductivity. The average value and the uniformity of the cooling efficiency changed with different inclined angles between the directions of the ATC and the mainstream. The highest average cooling efficiency was achieved with different values of the stream-wise angle α and the span-wise angle β when different regions downstream of the film cooling were considered. For example, when the blowing ratio was equal to 0.5, the corresponding α and β for the highest average cooling efficiency in the downstream region (1D ≤ X ≤ 5D) were 60° and 0°, respectively. For the downstream region (0D ≤ X ≤ 10D), the corresponding α and β were 35° and 60°, respectively. When the blowing ratio was different, the affected laws of α and β also exhibited variations.

The paper proposes a novel hybrid refrigeration system to convert industrial waste heat into refrigeration. The proposed system integrates Organic Rankine cycle, vapour compression cycle and liquid desiccant technology. The performance evaluation of the system recovering the waste heat from an industrial STACK has been conducted. The hybrid refrigeration system can potentially be used to convert industrial waste heat into refrigeration in the form of sensible cooling effect from vapour compression cycle and latent cooling effect from liquid desiccant unit. Results indicated under 200 kWth, the system can generate around 50 kW sensible cooling and 132 kW latent cooling effect, when the n-butane is the working fluid under 140 oC evaporating temperature. When the ORC condensation temperature is at 80 oC, the overall system COP ranges from 0.8 to 0.96.

Green roof systems have become an important part in creating sustainable cities. They can provide a wide range of economic, environmental, and social benefits. The goal of this research was to quantify the thermal performance improvements from a green roof with mineral wool substrate installed on a school building in a humid subtropical climate. In-situ measurements during a summer period included heat fluxes through the green and reference roof, vertical temperature profile through both roofs, the local air temperature above roofs, and local meteorological parameters. Furthermore, the summer thermal performance of green and reference roof and the green roof cooling effect were evaluated concerning meteorological parameters using the Pearson correlation analysis. The results indicate that the green roof layers have improved thermal performance of the roof with respect to reduced conductive heat flow by 57% and delayed heat transfer. The maximum and averaged reference roof to green roof outdoor surface temperature difference was 27.5 °C and 5.5 °C, respectively. It was found that ambient temperature and relative humidity have a dominant role on the thermal performance of the green and reference roof, while solar radiation and ambient temperature present the key meteorological determinants of the green roof cooling effect.

Besides air velocity, turbulence intensity and air temperature there are also other factors, which influence human thermal response to air movement. In this study, the impact of temperature fluctuations in airflow on human thermal sensation and perception of draught was examined. For the purposes of the study an air supply unit was designed for generating airflows with temperature fluctuations and used in a subjective experiment. The experimental study indicates that temperature fluctuations possibly influence the human perception of air movement with a distinct cooling effect. At high values of frequency and amplitude fluctuations a large discrepancy was found between predicted and measured values of draught discomfort.

Vertical greenery system (VGS) can provide a cooling effect on urban spaces. This paper conducted an experimental and simulation approach using the data logger and ENVI-met software during the summer and winter conditions in Tehran. The mean air temperature and relative humidity (RH) on those days were ~31.4 oC with ~37.8% RH on the summer day and ~6.1 oC with ~76% RH on the winter day, according to data retrieved from Tehran’s Mehrabad Airport’s synoptic station. The measurements were obtained on actual specification cases of VGS, and the temperature was recorded at certain points with definite distances from them. VGS were simulated in the ENVI-met on the same date. Hence, the purpose of this study is to evaluate of effect of thermal behavior on VGS in urban spaces in cold, semi-arid climate. The results showed that the temperature of VGS is cooler by 0.39–0.75 oC in the summer and 0.39–1.26 oC in winter. The effect of VGS was more remarkable at a distance of 0–0.5 m. Hence, building VGS creates and maintains an appropriate environment by reducing the temperature during the summer and increasing the temperature during the winter, creating a proper microclimate around itself. This is much more pronounced at a closer distance, but the effect fades away at a distance of 0.5 m.

This paper presents the outcomes and mechanisms of single droplet impacting on a heated solid surface with changing temperature. Two noncontact measurement techniques including a Thermal Infrared Imager and a High-speed Digital Recording Camera were adopted in the experiments to explore the cooling effect of the droplet on the heated surface with varying temperatures and to record the typical phenomena, respectively. Four typical impact regimes including flattening, bubble, transition from bubble to atomization and atomization during the droplet impact were observed and a comprehensive map based on non-dimensional analysis was built to describe the relationships among the typical regimes. For quantitative analysis, the empirical correlations were acquired to predict the non-dimensional maximum spreading diameter based on non-dimensional analysis. The non-dimensional droplet resident time decreases linearly with the increase of T w T s a t log 10 Re . The heat flux of average droplet was calculated and the result showed that it increases with the non-dimensional parameter T w T s a t log 10 Re .The transient temperature of the heated surface was measured to quantify the effectiveness of cooling.

For the impacting-freezing process of the droplet on cold surfaces, more studies have focused on stationary surfaces, while moving surfaces have received less attention. Here, a three-dimensional numerical model based on the VOF model and the Solidification/Melting model is established to numerically study the impacting-freezing process of the droplet on a lateral moving cold superhydrophobic surface, and focusing on the morphology evolution of the droplet and the initial freezing location. For the lateral moving surface, five different morphology distributions were observed during the impacting-freezing process of the droplet: full rebound, near full rebound, partial rebound, near full adhesion and full adhesion. The initial freezing location of the droplet preferentially appears on the upstream side of the droplet. The freezing on the downstream side of the droplet lags behind that of the upstream side due to the cooling effect of the cold surface, and the lagging effect is strongly influenced by the cold surface temperature. Moreover, the effects of cold surface temperature, supercooling degree and impacting Weber number on the spreading factor during the impacting-freezing process of the droplet are also discussed. The effect of the cold surface temperature on the spreading factor is greater than that of the supercooling degree. And a unified morphology distribution map of rebound and adhesion of the droplet is plotted based on the weighted average temperature and the impacting Weber number, which can show the competitive relationship between droplet impact hydrodynamics and droplet solidification.

Climate change will alter thermal comfort very differently depending on the future scenario selected. This research computes two bioclimatic indices: Physiological Equivalent Temperature (PET) and Universal Thermal Comfort Index (UTCI), in the area of Tabriz (Iran), considering an observational period (1960 to 2020) and three projected scenarios (RCP2.6, RCP4.5, and RCP8.5) associated to greenhouse gas concentrations for the period 2030 to 2059 and 2060 to 2100. The CanESM2 model was used to estimate projected data. Thermal comfort for these three periods are compared at daily basis attending to the sky conditions (clear and cloudy) and the presence or absence of wind. The study of the observational period shows that the cloud cover effect has increased PET and UTCI values by 0.82 and 0.51°C, respectively. For the projected period, it has been found an increase in PET and UTCI values by 0.36 and 0.42°C associated to the presence of clouds. On the other hand, a decrease in temperature of 10°C for PET and 11.73°C for UTCI is found in the observational period when windy and calm days are compared. This cooling effect of the wind will decrease in the projected period where temperature reduction based on PET and UTCI values is estimated to be 4.5 and 8.4°C for 2030-2059 and 2.5 and 5.2°C for 2060-2100 respectively. In conclusion, future changes in clouds and wind will clearly impact thermal comfort in the city of Tabriz in the future decades. Both the projected cloudy heating effect and the reduction of the potential of cooling of the wind, will have serious implications for heat-related diseases and different socioeconomic activities in the region. Accordingly, the definition of mitigation and adaptation strategies in short term should be a priority.

We investigated the effect and mechanism of the emission characteristics on the thermionic emission cooling (TEC) effect using the prepared W-La2O3 cathode in the temperature range of 2050–2350 °C. The experimental and calculated results showed that the TEC effect and the current density of cathodes increased non-linearly with temperature. Under high temperatures, the initial velocity of emission electrons provides a significant contribution to improving the TEC effect. The emission current flow patterns corresponding to the cathodic emission characteristic region under operating conditions determine the magnitude and trend of the TEC effect, which can be well interpreted by the high-temperature thermionic emission (HTTE) model.

Summer increasingly gets hotter, which has become a common problem that threats human settlement environment and hinders urban sustainable development. The impacts of urban morphology on land surface temperature (LST) have been studied extensively, but the investigation from the local climate zones (LCZs) perspective is less concerned. We thus explored the relationship between 2D/3D urban morphology and spatial variation of LST across seasons based on LCZs by utilizing high-resolution remote sensing images and vector building data. The results showed that: (1) the spatial distributions of seasonal LSTs took a circle structure with three rings from the city center to the fringe area. In particular, the temperature showed a characteristic of “High-Low-High” in spring, autumn, and winter. However, the LSTs in the first ring were 1.4 °C and 2.2 °C higher than the second and third ring in summer, respectively. (2) The inter-LCZs differences of LST were consistent across seasons. In summer, the warmest zones were LCZ 2 and LCZ 3 with 2–3 °C higher than other built type LCZs, while the coldest zones were LCZ A and LCZ G with 4–6 °C lower than other land cover type LCZs. (3) The most influential 3D factor on LST was the mean building height with a significant cooling effect in LCZ 1, LCZ 3, and LCZ 4 in spring and autumn. Impervious surface fraction was the dominated 2D factor with a significant warming effect in all seven built type LCZs in summer.

In order to solve the high temperature problem of the pavement, the prepared 2DMts/SA phase change energy storage composite material was added to the geopolymer-based inorganic heat reflective coating to construct a new coating with TiO2-2DMts/SA. Among them, 2DMts/SA has good energy storage characteristics (242.37 J/g) and cycle stability. Through indoor cooling test and outdoor cooling test, the actual cooling effect of traditional heat-reflective coating (coating with TiO2) and novel coating with TiO2-2DMts/SA was compared. The results showed that coating with TiO2-2DMts/SA has a better cooling effect under both indoor and outdoor test conditions. Compared with control check sample, coating with TiO2-2DMts/SA sample reduced 24.8 ℃ and 7.29 ℃ on average under two kinds of conditions, respectively. The novel coating with TiO2-2DMts/SA can further absorb the unreflected heat energy when TiO2 greatly reflected the heat radiation, thereby delaying the increase of pavement temperature.

Studies on the interactions between landscape patterns and land surface temperature (LST) are critical to mitigate urban heat islands (UHIs). However, integrated spatial indices combining both composition and configuration to quantify this relationship requires further development. We present an index of spatial connectivity between patches of the heat source and sink (SCSS) to assess the heterogeneity impact of landscape patterns on LST in Wuhan, China. We examined the relationship between LST and SCSS at the urban (within the urban growth boundaries, UGBs) and city levels, using spatial regression analyses. Results show that: (1) the SCSS and LST presented a significant negative correlation, and the SCSS can explain 76% and 81% of the variability in LST at city level and urban level, respectively; (2) for every 0.1 increase in SCSS, the LST will decrease by 0.96 °C at city level, and 1.67 °C at urban level; (3) the percentage of the source landscape area should be no more than 62% and the SCSS should not fall below 0.18 to control the UHI effect; (4) maintaining the percentage of the source landscape area at below 18%, and the value of SCSS at over 0.43, will help to bring about a significant cooling effect. Our findings allow a better understanding of the interactions between the spatial heterogeneity and the thermal regulation function of landscapes and provide insights for urban planners to mitigate the UHI effect.

Urban green spaces (UGSs) reduce the surrounding temperature and create cooling areas as a buffer between people and high temperatures, thus helping residents adapt to the warming climate. However, the accessibility of UGS cooling services to the residents of cities remains largely unknown, which hinders decision-making regarding the formulation of climate adaptation and urban greening schemes. In the present study, we estimated the number of residents who accessed UGSs for cooling by analyzing the annual changes in such cooling areas during summer across 315 Chinese cities from 2003 to 2015. Approximately 93.3% of the cities showed significant decreasing trends (p

Floating photovoltaic systems are an attractive, emerging concept to extend the area available for solar energy production to the water. Among the advantages of floating PV, frequently a cooling effect is mentioned. Yet little to no quantitative information about this cooling is provided in available literature. In this study, we present observations that challenge the role of water for photovoltaic module cooling. When comparing temperatures of two photovoltaic installation in Cambodia, we found that photovoltaic modules from a commercial floating installation at noon were significantly (9.1 ± 2.8 K) hotter than those from a nearby, small-scale installation on a metal rooftop. This large difference was all the more unexpected because the rooftop installation was on top of a room with electronic equipment that generated additional heat. When reproducing the temperatures of either system by modeling, we found that the most likely cause for this temperature difference is different exposure to wind of the two installations due to different PV module heights. Comparing temperatures at night, we find that the floating installation is 1.2 ± 0.5 K cooler than the rooftop installation. This difference can likely be attributed in parts to evaporation cooling. We conclude that the presence of water is a minor- or an indirect factor in the thermal balance of floating photovoltaic installations. Exposure to wind and module height are the differentiating elements for photovoltaic system cooling, at least in areas with small overall wind speeds.

Through the effects of global warming, rising temperatures is becoming an increasing problem for fruit production. Pyrus pyrifolia ‘Nijisseiki’ is a famous Japanese pear cultivar that was introduced to East China in the 1930s. However, ‘Nijisseiki’ pears showed great inadaptability to the cultivation environment, and do not provide good yield when grown in East China where temperatures are higher than Japan. Here, we introduced two cooling measures, mist spray and shade cloth treatments, to test for whether they can mitigate heat-induced damage to ‘Nijisseiki’ pear. This study was conducted in summer of 2013, 2014 and 2015 at Yangzhou (Jiangsu, China). A typical weather model was established to evaluate the cooling effect of each treatment. The results showed both treatments were maintaining regular levels of the photosynthetic system utilization and antioxidant enzyme activity, and reducing damage from ROS compounds. The shade cloth treatment decreased excessive growth, promoted spur growth and higher SPAD value but delayed its maturity than those treated with mist spray. Both treatments increases yields per tree. Considering the cost, shade cloth treatment is the reasonable cooling measure on ‘Nijisseiki’ pears in Yangzhou. In addition, eight PpyHsfs that showed gene expression level changes based on temperature. And HsfA3b was the most sensitive to high temperature.

The purpose of this study is to investigate the temperature effects on the bond strength between concrete and steel reinforcement bars. For two different steel bars (epoxy-coated and uncoated bars), three experimental parameters (heating rate, target temperature, and cooling condition) are examined. At a target temperature of 200 °C, the epoxy-coated rebar has much higher bond strength than the uncoated rebar. However, in the specimens exposed to target temperatures higher than 200 °C, the test results show that the epoxy coated rebar has less bond strength than the uncoated rebar. Also, the test results demonstrated that as the heating rate and target temperature increase the bond strength decreases. The cooling method does not affect the ultimate bond stress of the specimens using uncoated rebar very much but can greatly affect specimens that contained epoxy coated rebar. A more in-depth study can be considered regarding the cooling effect on the bond strength.

Temperatures in urban area rise; therefore, it is necessary to consider the mitigation of urban warming. Considering that, in coastal areas such as Yokohama, an effective mitigation could be based on sea breeze patterns during summer daytime, this study aims at analyzing the relationship between temperature distributions and sea breeze fronts. Eventually, the target of this paper could be the creation of an Urban Environmental Climate Map (UECM) showing mitigation measures for each zone. Firstly, fine weather days are extracted and the sea breeze blowing patterns are classified in the target area. Secondly, the wind and temperature distribution patterns are mapped using WRF. The results obtained enable the mapping of the sea breeze fronts and the analysis of the relationship between temperature distributions and sea breeze fronts. Finally, a spatial zoning is performed. The results are presented as follows: 1) Sea breeze blowing patterns are classified into three patterns; 2) Based on the numerical simulation results and the temperature data observed in coastal areas, southwest wind has a cooling effect; 3) The target area is classified into “Sea breeze arrival zone” and others based on the presence of a see breeze; 4) An UECM showing proper mitigation measures is proposed.

Pedestrian-level wind environment in urban areas has a significant impact on the quality of urban dwellers' daily life. For pedestrian-level wind studies in severe cold regions, the cooling effect of wind and related thermal discomfort in winter is quite significant. However, thermal effects of wind are not considered in most wind comfort studies and wind comfort generally only refers to the mechanical effects of wind on people. Therefore, particular consideration is given to the chilling effect of wind on exposed skin and risk of frostbite in winter, and a wind chill criterion based on the wind chill temperature is proposed in this study. The pedestrian-level wind conditions in seven representative residential areas summarized from cities in severe cold regions of China are assessed based on the wind mechanical comfort criterion of NEN 8100 and the wind chill criterion. CFD simulations are performed to provide the pedestrian-level aerodynamic information, and the simulation results are validated by wind tunnel experiments. The assessment results show that the wind mechanical comfort or wind chill criterion need to be combined when assessing the wind conditions in severe cold regions. From the perspective of wind mechanical comfort and wind chill, the multi-storey residential areas with hybrid-type and the enclosed-type layout are recommended in severe cold regions. Moreover, a strict control of building height in residential areas is important to improve the pedestrian-level wind mechanical comfort, but not very helpful to reduce the occurrence of frostbite in winter.

We have investigated the superelastic behavior and elastocaloric effect in [011] oriented Ni50Fe19Ga27Co4 single crystals. The superelasticity is absent in a temperature gap of 60 K. At the critical temperature of 388 K, the stress oscillation and audible noise can be found during the superelastic deformation, indicating the occurrence of burst-like transformation. Such a burst character leads to a novel non-linear increase of martensitic transformation start stress with temperature, and an enhanced hysteresis loss. In addition, a large elastocaloric temperature window of 40 K and a maximum cooling effect of −6.1 K have been obtained.

Green roof and night-time ventilation are promising passive cooling strategies. These two strategies and walls insulation have been researched separately in many studies. In this paper, a new strategy combining the three techniques together is discussed. Based on the analyses of a field experiment of a single-story building with green roof in Shanghai, a model was established using DesignBuilder software and validated with the experimental building. And then, the model with green roof was simulated in three cases: no ventilation, night-time ventilation and night-time ventilation combined with walls insulation. Results show that when the night ventilation operated, the indoor temperature under green roof decreased while the air change rate increased. With the improvement of external walls insulation, the cooling effect of the night ventilation becomes more obvious for the extensive green roofs. Additionally, a simplified multiple regression model is proposed to assess the passive cooling of green roof which combined with night ventilation and walls insulation in hot and humid regions. According to the model, for a building with green roof, the indoor average temperature can be reduced by up to 2.3 °C compared with the building combined with night ventilation and walls insulation together.

While research has demonstrated that brownfield sites and vacant lots in inner-city areas have a cooling effect on the micro climate, less is known about how this effect changes during the redevelopment of a brownfield. It is often argued that redevelopment will lead to a loss of cooling effects. The connection between cool and compact cities is especially of interest as brownfield redevelopment is an important element of sustainable urban development strategies such as the dense city. We evaluate potential tensions between the Ecosystem Service of regulating the micro climate and urban densification processes using an empirical example, the case of the brownfield redevelopment of Bayerischer Bahnhof in Leipzig, Germany. We apply ENVI-met modeling and a virtual reality display system visualization to assess the complex connections between cool and compact cities. Our findings demonstrate that a co-existence between regulating the urban micro-climate and dense urban structures is possible. Smart urban planning approaches can, if properly implemented, reduce the so called “paradox of the compact city” and lead to cool and compact urban areas. Through ENVI-met modeling and virtual reality display system visualization, the complex connections between cool and compact could be assessed.

Film cooling is an effective technique that protects chamber walls in rocket combustion against chemical attacks and heat fluxes. This study discusses cooling effect in a multi-element GO2/CH4 splash platelet injector. Influence parameters, such as slot height, slot number, percentage of coolant, and injection position on cooling effect, were investigated. GCH4 with 298.15 K was applied as film coolant. In the first step, slot heights of 0.2 and 0.4 mm were compared by applying a constant film mass flow rate. Temperature, CH4 mole fraction distribution, and flow field structure were obtained. The effects of slot number, percentage of coolant, and injection position on wall temperature distribution were then determined. Finally, the reasons for the low cooling efficiency were analyzed. Improvement in the method is proposed to achieve improved cooling effect for splash platelet injectors.

In order to analyze the influence of four parameters on the cooling effect of a liquid-cooled battery thermal management model, a L16(44) orthogonal array is selected to design sixteen models to perform and quantify the parametric to identify the main and secondary factors, then the optimal combination model is found. The results show that the number of the pipe has most obvious effect on the average temperature of the cooling plate in the four parameters, and velocity of coolant flow is second, pipe height has the minimal effect. In terms of temperature uniformity, amount of pipe and velocity of coolant have similar effects which are both main factors, pipe width and pipe height have similar effects which are both secondary factors. The optimal case by this orthogonal analysis can meet various cooling conditions.

In the present work, field measurement and simulation method were employed to investigate the effects of several green roofs variables on regional thermal environment in Chongqing (29°N, 106°E), China. Field experiments were conducted in two typical places. The real influence of green roofs on ambient environment was analyzed and compared with the simulation results. The software ENVI-met was employed to simulate 29 cases with different factors, including green roofs types, vegetation coverage, building height, arrangement position and regional layouts. With the aim to investigate the effect of the green roofs thoroughly, different design factors of green roofs were taken in consideration. From the aspect of cooling effect, it can be found that enclosing layout has the maximum air temperature drop, which is up to 0.5 °C. From the perspective of the uniformity of regional environmental temperature distribution, the regional thermal environment of scattered layout is better than enclosing and array layout as a whole. In addition, with the same vegetation coverage, the effectiveness of air temperature dropping of the whole region differed according to the arrangement position. Centrally arranging the green roofs upwind can effectively reduce the air temperature of the whole region. These findings can be used to improve the regional thermal environment by designing the green roofs reasonably.

A new type of fire suppressant powders of magnesium hydroxide (Mg(OH) 2 ) modified by DOPO-VTS has been manufactured. And the fire suppression effectiveness and physical-chemical properties were studied in this paper. Three kinds of powders were used to study their fire suppression efficiency through laboratory scale experiments in a confine space of 1*1*1m. The physical and chemical characteristics of pure Mg(OH) 2 and its modified powder were characterized by thermal gravity analysis (TGA) and X-ray photoelectron spectroscopy (XPS). The results exhibited that these three kinds of powder were all high efficient for fire suppression and the modified Mg(OH) 2 powders by added 3% DOPO-VTS was more efficient than the Mg(OH) 2 powders added 1% DOPO-VTS and the origin powder. And the modified Mg(OH) 2 powder by added 3% DOPO-VTS could release the least CO and decrease the flame temperature sharply. Fire extinguishing and possible fire-suppression mechanisms have also been analyzed from three aspects: chemical inhibition, cooling effect and asphyxiation effect.

A method of fabricating an industrially scalable, widely applicable, and easily repairable superhydrophobic self-cleaning cool orange-gray coating using commercially available materials and following a simple industrial procedure is introduced. Grinding the coating surfaces using an appropriate emery paper creates microgrooves with suitable widths and exposes micro- and nanoparticles on the coating surface. Both factors together endow the coating surfaces with superhydrophobic self-cleaning properties. The hydrophobicity of the coating possesses good resistance to alkali, acid and mechanical abrasion. Grinding the coating surfaces using emery papers also increases the solar reflectance of the coating. The cooling effect of the superhydrophobic coating, which has a solar reflectance of 0.815, is estimated to be 23 °C relative to concrete on a typical clear summer sunny day. Although the superhydrophobic self-cleaning property and solar reflectance of the coating may be compromised by artificial accelerated weathering, the superhydrophobic self-cleaning property can be easily and fully reestablished and the inclined solar reflectance may be partially restored after the coating surfaces are ground using an appropriate emery paper.

Remotely sensed thermal data are applied widely in ecology studies, although the resolution of them is usually low. The spatial enhancement of thermal images (TSE) will play an important role in ecological applications. This paper used emissivity modulation (EM) for the TSE, and then used the images to estimate the urban cooling effect with three popular approaches: the local climate regulation index (LCRI), cooling intensity (CI), and green cooling island (GCI). After TSE process, the results of LCRI and CI showed little statistical difference, although the spatial differences should not be overlooked. The GCI results changed clearly after the TSE, with a 38.1% decrease of the area of cooling extent. Therefore, the TSE is recommended for GCI and green patch level CI, and not for LCRI or regional CI.

For the field of cool material, barium titanate (BaTiO 3 , BT) is still a new member that needs to be further studied. Herein, the effects of both content and surface hydrophobic modification of BT on the cooling properties of acrylonitrile-styrene-acrylate copolymer (ASA) were detailedly investigated, aiming to fabricate composited cool material. Butyl acrylate (BA) was employed to convert the surface of BT from hydrophilic to hydrophobic. The addition of unmodified BT could significantly improve the solar reflectance of ASA, especially when the addition amount is 3 vol%, the near infrared (NIR) reflectance increased from 22.02 to 72.60%. However, serious agglomeration occurred when the addition amount increased to 5 vol% and therefore led to a relatively smaller increase in solar reflectance and an obvious decline in impact strength. After surface hydrophobic modification, the modified BT (M-BT) presented better dispersibility in ASA matrix, which contributed to the improvement of both solar reflectance and impact strength. In addition, the temperature test provided a more sufficient and intuitive way to evaluate the cooling effect of the composited cool materials, and a significant decrease (over 10 °C) could be achieved in the temperature test when M-BT particles were introduced.

The thermal protection technology for high-temperature environment has made great progress in recent years. Restricted by the harsh environment of oil drilling, the design and development of measurement-while-drilling instrument (MWD) for high-temperature wells are still a worldwide issue. Although quite a few scholars have proposed a variety of thermal protection schemes, the feasibility or practical using effect has not been fully verified. Through comparative analysis of various cooling methods, it is considered that the active cooling scheme based on split-Stirling refrigerator is feasible, and a set of active cooling system is designed. The temperature distributions on the circuit cabin are presented. The influences of the structure parameters of circuit cabin, circuit board and refrigerator, the thermal conductivity of insulation material, the cooling power of refrigerator, the circuit board power, the annulus and water eye temperature on the cooling effect are discussed. The results show that the circuit board structure parameters, the insulation material thickness and thermal conductivity, the ratio between circuit board power and cooling power of split-Stirling refrigerator, the temperature difference between water eye and annulus are the key parameters affecting the cooling effect.

The bunkering process is an important issue of the operation of liquefied natural gas (LNG) fueled ships. In this paper, an analytical model was developed to predict and investigate the thermodynamic behaviors of marine LNG fuel tanks during no-vent bunkering operations. The complex heat and mass transfer phenomena inside the cryogenic tanks were considered and modeled. A spray droplet model was developed to quantitatively evaluate the vapor condensation and cooling effect in the tank during top spray filling. The validity of the model was confirmed by the measured data on a Norwegian car ferry. The results show that the vapor condensation and cooling at the droplet-vapor interface dominate the top spray filling process, while the vapor compression dominates the bottom filling process. The impact of vapor condensation on the tank pressure during top spray filling is around 2.6 times as large as the vapor cooling. Furthermore, parametric study reveals that the bunkering performance is very sensitive to the LNG supply temperature and droplet diameter.

Liquid nitrogen has excellent ability of cooling and asphyxiating, which is suitable for fire extinguishing in urban underground utility tunnel. In order to obtain the influence of injection method on the fire extinguishing efficiency, a medium-sized square utility tunnel was built. Fire extinguishing experiments with different liquid nitrogen injection methods and distances were carried out. The distribution and the decrease law of oxygen volume fraction and temperature are analyzed. The result shows that the time to extinguish the fire and enter the controllable stage are greatly reduced under both conditions. Among them, the fire extinguishing efficiency of vertical injection is higher. Liquid nitrogen accumulates near the injection port first, which has a great cooling effect on this area, and acts on the fire in two stages. As the distance increases, the cooling effect is weakened and the oxygen volume fraction increases stepwise. Liquid nitrogen shows continuous cooling and asphyxiating effect during horizontal injection. It moves fast in this mode, so the difference in oxygen volume fraction is small. The initial cooling effect of vertical liquid nitrogen injection is better than that of the horizontal injection. However, the temperature at the end recovers earlier after fire extinguishing in the latter condition.

As single urban landscape elements, buildings and trees have important impacts on the urban microthermal environment. Thus, the interaction between trees and buildings requires more thorough investigation. In this study, typical residential districts in Nanjing, Jiangsu Province, China, are selected as the research area, and different evaluation indexes are established to explore the influence of trees on building surface temperature. ENVI-met simulations of the different established scenarios based on the spatial configuration analysis of buildings and trees in the study area were performed to determine the influence of the distance between individual trees, the distance between trees and walls (spatial position) and the leaf area density (LAD) value (attribute) of trees on the surface temperature of buildings. The results showed that 1) the best wall cooling times in the east, west, south and north were 12:00, 17:00, 14:00 and 16:00, respectively; 2) the best cooling effect was achieved at vertical heights of 12–14 m; 3) a compact tree arrangement reduced the shortwave radiation that reached the wall during the daytime by a large extent and thus had the best cooling effect in all scenes; and 4) trees with an LAD of 1.1 led to 20 °C greater cooling for a brick in one day than trees with an LAD of 0.3. This research attempts to reveal the influence of trees on building surface temperature and provide the corresponding decision basis for tree planning in residential areas to reduce the impact of urban heat pressure on human health and energy consumption.

The aggravating impacts of the urban heat island phenomenon in Philippine cities has motivated planners to utilize urban green and blue spaces as a potential mitigation strategy. This study aims to assess the cooling effect (CE), heat reduction (HR), and energy saving potential (ESP) of trees and water along the Iloilo River Esplanade located in Iloilo City, Philippines. Microclimate modelling and simulation during summertime were performed using ENVI-met software and validated using field observations. Results of the study show that the urban park can provide a maximum CE of 2.63°C at 3:00 PM near the southern edge of the river, which is equivalent to a HR of 13,564 J and an ESP of 1.09 × 10−2 kWh. Meanwhile, a temperature increase of up to 0.16°C can be observed at night due to the nocturnal warming effect of water. In terms of spatial distribution, CE, HR, and ESP tend to gradually decrease as the horizontal distance from the park and altitude increases. Moreover, wind direction may also increase the scale and intensity of CE downwind, but it has an opposite effect in areas upwind.

Large eddy simulations (LESs) were conducted to investigate the effects of wall cooling on the separated flow transition over a highly loaded compressor blade at two Reynolds numbers of 2.0 × 105 and 1.0 × 105. The locations of transition onset and completion were identified by linear stability theory (LST). As the transition was triggered, the streamwise gradient of the near-wall temperature increased to a higher level. Therefore, the transitional region can be roughly diagnosed through the distribution of temperature. Results showed that wall cooling weakened the relative role of turbulent dissipation in suppressing rapid amplification of disturbances, which promoted the transition process and reduced the length of the transitional region. Compared with the case of the adiabatic wall, the scale of three-dimensional vortex structures on the cooled wall was reduced, and the vortex rolling-up and breakdown were weakened. For such conditions, the region of high-level Reynolds shear stresses shrunk and the loss generation rate declined. By comparison, the effect of wall cooling on controlling the transition process was more pronounced at a lower Reynolds number, and the profile loss was reduced by 18.23% and 25.05% at Reynolds numbers of 2.0 × 105 and 1.0 × 105, respectively.