Energy sector plays an important role in country’s economic development and it is going to be more significant in years to come. Managing this growing energy demand at reasonable cost therefore assumes national priority. A multidimensional approach is required keeping in view the various economic options available with effective demand management. Development towards the advances in automobile ...

over a period of three months (summer), 108 samples of water collected from four hospitals in te-hran. they were taken from numerous potable and non-potable water, including main supply cis-terns, calorifiers, hot and cold tap water, shower, cooling tower and drain of air condition system. culturing of concentrated and non-concentrated water samples on buffered charcoal yeast extract (bcye) aga...

The purpose of this paper is to introduce the development of a unique compressor capacity modulation concept which utilizes reexpansion volume as a means of capacity reduction in hermetic air conditioning and refrigeration system. While there are various methods of compressor capacity modulation in use, each particular method is limited in its application or appeal for different reasons such as...

In recent years, several research activities have been conducted to develop knowledge in analysis, design and optimization of compressor anti-surge control system. Since the anti-surge control testing on a full-scale compressor is limited to possible consequences of failure, and also the experimental facility can be expensive to set up control strategies and logic, design process often involves...

The objective of this project is to investigate an energy efficient air conditioner to be able to compete with conventional vapour compression systems. Liquid desiccant air dehumidifier/indirect evaporative cooling using cross-flow type Plate Heat Exchanger (PHE) as dehumidifier offers a cost effective and more environmentally friendly air conditioning system. It removes moisture form the air a...

Sonny G. Sundaresan Copeland Corporation Sidney, Ohio, U.S.A. HCFC 22 currently used in Air-Conditioning and Heat Pump applications, is being replaced by R407C and R410A, both HFC 32 based blends. Scroll compressors are being developed to meet the improved efficiency and other system performance requirements in Air-Conditioning and Heat Pump products in North America, Europe and Asia-Pacific. L...

In the article, possibility of determining consumption electrical energy by gas air cooling devices. Special attention is paid to processing experimental results. There are some assumptions in mathematical model that do not affect final result. The factors influencing electric coolers given. It stated ambient temperature and pressure significantly energy. Thus, based on data, a devices main com...

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 conditioning refrigerant r134a has value of global warming potential (gwp) 1300, which is much higher than mac directive (gwp below 150) passed in july 2006. this prompted a search for alternative refrigerant with gwp value less than 150. r1234yf is a new refrigerant which has lower gwp value of 4. effect of blower speed has been compared and flammability issue of r1234yf has been addressed...

A single screw compressor is usually sealed by means of its tiny clearances. The theoretical research and the practice application shown that the leakage in the working process is always the key factor influencing the performance of this kind of compressor. Besides meeting the need of lubrication, the oil injection can greatly improve the sealing effect. It is obvious that the reduction of clea...