Air conditioners have great potential to participate in power system frequency control. This paper proposes a control strategy to facilitate the active participation of air conditioners. For each air conditioner, a decentralized control law is designed to adjust its temperature set point in response to the system frequency deviation. The decentralized control law accounts for the user’s thermal...

There is a demand for reduced power consumption in the vapor compression refrigeration cycle. Coefficient of performance of window-air conditioners considerably decreases and power consumption increases under very hot conditions. These problems have encouragecl studies aimed at improving the performance of window-air-conditioners by enhancing the heat transfer rate in the condenser. In this ar...

There is a demand for reduced power consumption in the vapor compression refrigeration cycle. Coefficient of performance of window-air conditioners considerably decreases and power consumption increases under very hot conditions. These problems have encouragecl studies aimed at improving the performance of window-air-conditioners by enhancing the heat transfer rate in the condenser. In this ar...

Air conditioners are commonly used to keep electronics cool in various areas, such as industrial automation, telecommunication equipment, security and defense systems as well as other indoor and outdoor electronics applications. The electronics may be housed in protective enclosures, where air conditioners deliver cooled air to keep the entire enclosure at desired temperatures for optimum elect...

Along with BACnet, LONWORKS is also increasingly accepted as a de-facto standard for building management communication protocol. A few years ago, Mitsubishi Heavy Industries developed these communication gateways for packaged air-conditioners,(1) but the recent market need is increasingly shifting to large capacity and high performance. In recent building management systems for packaged aircond...

Increased awareness of the impact of chlorofluorocarbons (CFCs) on the global environment has become the impetus in searching for alternative refrigerants and cooling methods for automotive air conditioning. Automotive air conditioning is one industry that heavily uses CFC compounds, and the leakage of CFCs from such air conditioners is substantial compared to that from stationary air condition...

In Japan, the refrigerant used in room air-conditioners has been changed from HCFC-22 (R-22) to R-410A, a blend of HFC-32 and HFC-125 (50/50 vt%), in order to protect the ozone layer. Generally, the miscibility between the refrigerant and refrigeration oil must be assured, because the oil needs to return to the compressor from the refrigeration cycle and lubricate the sliding parts. Alternative...

In this paper, the application of evaporative cooling for refrigeration cycle to reduce power consumption in hot climates is emphasized. Experimental and analytical investigations were performed in order to specify the effect of evaporative cooling condenser instead of the commonly used air cooling condenser in window-air-conditioners. Evaporative condenser can reject more heat, thereby preve...

This paper presents technical assessment of environmentally friendly refrigerants as alternatives to R410A for window air conditioners. The alternative refrigerants that are studied for its replacement include R32, R600a, R290, R1234yf, R1234ze and a mixture of R32 (90% molar concentration) and R125 (10% molar concentration). Baseline experiments were performed on a window unit charged with R41...