Seasonal Cooling Effect of Vegetation and Albedo Applied to the LCZ Classification of Three Chinese Megacities

The urban heat island effect poses a growing threat to human society, especially in densely populated and developed megacities. With the introduction of the Local Climate Zones (LCZ) framework, new perspectives and findings have been brought to urban heat island studies. This study investigated the cooling effect of vegetation and albedo on the...

Characterizing the thermal effects of vegetation on urban surface temperature

Vegetation is important for urban heat mitigation. The cooling intensity of vegetation is affected by background climate and urban design. How to evaluate vegetation cooling efficiency under different climate conditions is still an issue open to discussion. In this study, a normalized indicator of urban vegetation cooling efficiency (NVCE) is...

Experimental investigation of absorption in upward and downward flow of NH₃-CO₂-H₂O in a mini-channel heat exchanger

Heat pumps can drastically reduce energy requirements in industry. Operating a compression resorption heat pump with an NH₃-CO₂-H₂O mixture has been identified as a promising option that can have an increased performance compared to only NH₃-H₂O. In this paper an important process of the...

Parameterization of urban sensible heat flux from remotely sensed surface temperature: Effects of surface structure

Sensible heat exchange has important consequences for urban meteorology and related applications. Directional radiometric surface temperatures of urban canopies observed by remote sensing platforms have the potential to inform estimations of urban sensible heat flux. An imaging radiometer viewing the surface from nadir cannot capture the...

Absorption of Ammonia-Water and CO2-NH3-H2O Mixture in Mini-Channel Heat Exchangers

The energy consumption in the industry field is considerable. Saving energy has great potential in many industrial processes. For example, heat recovery from the spent cooling water can be achieved by applying heat pump technology, and the recovered heat can be used for district heating. Previous study indicates that the compression-resorption...

Absorption of CO₂-NH₃-H₂O mixture in mini-channel heat exchangers

Compression resorption heat pumps (CRHP) are a promising option to upgrade waste heat from industry. Alternative working fluids can further improve the efficiency of CRHP. The ternary mixture NH3-CO2-H2O has been identified as a promising working fluid for CRHP and has the potential to further enhance the coefficient of performance (COP) of the...

Control strategies of CO₂ refrigeration / heat pump system for supermarkets

CO2 is a promising refrigerant compared to traditional HFCs due to its insignificant global warming potential and nonthreatening to the ozone layer. It has been used as refrigerant in industrial and commercial refrigeration in recent years. With high compactness and the ability to recover heat, CO2 booster systems have been widely installed in...

Heat Transfer in the Thick Thermoset Composites

Nowadays more and more large composites are used to replace the traditional metallic structural materials in the industries. However, for manufacturing the thick thermoset composites, the size not only influences the mechanical properties in the completed products, but also the core temperature overshoot generated during the curing reaction....