Although water-cooled chillers are more energy efficient than air-cooled chillers, a majority of chilled water systems use air-cooled chillers. In cold weather climates, air-cooled chillers are capable of functioning in low ambient temperatures with few operational concerns, where as water-cooled chiller systems must be equipped to prevent cooling tower freezing. The integrated chiller system a...

the present paper describes the designing of a thermally and economically optimum mechanical draft counter-flow wet cooling tower. the design model allows the use of a variety of packing materials in the cooling tower toward optimizing heat transfer. once the optimum packing type is chosen, a compact cooling tower with low fan power consumption is modelled within the known design variables. mor...

R-502 has been the primary refrigerant for low temperature commercial refrigeration applications for many years. The impending phase-out of CFCs dictates its elimination in the very near future. The identification of alternative(s) for R-502 therefore becomes a high priority. This paper addresses the factors to be evaluated in selecting the best replacement and identifies an azeotropic mixture ...

This paper summarises the work of a 5-year research programme into the heat transfer within cavities adjacent to the main annulus of a gas turbine. The work has been a collaboration between several gas turbine manufacturers, also involving a number of universities working together. The principal objective of the study has been to develop and validate computer modelling methods of the cooling fl...

since the energy analysis considers the quantity of energy, it cannot show the performance of the cooling tower. therefore, in order to optimize the performance of the tower and also the process which the cooling tower is a part of it, it is necessary to analyze the energy and exergy of the tower simultaneously. in this paper, the energy and exergy of one of the cooling towers of khuzestan stee...

In order to solve the problem of poor refrigeration performance during operation system under low temperature conditions, this paper designs a test bench study effect different air volumes on cooling capacity conditions 32?C outside warehouse and -10?C inside warehouse. The results show that when volume condenser is set 65% unit evaporator 100%, 8.62 kW, compressor power 1.88 COP 4.55 energy ef...

The frrst part of this paper presents carbon dioxide air conditioning units which were installed in two city buses. The two buses were tested "on-the-road" during summer 1997 in Bad Hersfeld, Germany. By the end of 1997, the air condition systems of the two buses had been running together for more than 860 hours proving that C02 systems fulfill important on-the-road requirements. In the second ...

During the process of refrigerant alternative, R290 (propane), as a nature refrigerant used in Room Air Condition (RAC) system, is thought as a long-team substance and has attracted great attention. This paper simply introduced the characteristics and standard demands of R290 application, then, based on a 1HP R290 DC INV. RAC system at first, then finished the comparison test when a one-cylinde...

In recent years, energy engineers have examined industrial compressed air systems looking for opportunities to reduce the energy consumption, which in turn leads to operating cost savings. After identifying possible actions that might lead to a reduction in energy usage, it is necessary to perform an analysis to determine the projected energy and cost savings, and to estimate the cost of implem...

A stage-by-stage wet-compression theory and algorithm have been developed for overspray and interstage fogging in the compressor. This theory and algorithm are used to calculate the performance of an 8-stage compressor under both dry and wet compressions. A 2D compressor airfoil geometry and stage setting at the mean radius are employed. Six different cases with and without overspray have been ...