An experimental investigation was implemented to determine the capacity degradation due to non-uniform refrigerant and air flow distributions, and to assess the potential to recover the lost capacity via controlling refrigerant distribution between individual refrigerant circuits. The tests were performed on a three-circuit, threedepth-row, finned-tube evaporator. Refrigerant inlet quality, exi...

Optimizing the refrigerant circuitry for a finned-tube evaporator is a daunting task for traditional exhaustive search techniques due to the extremely large number of circuitry possibilities. For this reason, more intelligent search techniques are needed. This paper presents and evaluates a novel optimization system, called ISHED1 (Intelligent System for Heat Exchanger Design). This system uses...

In this paper, mini-channel type evaporator which is new in mobile air conditioning (MAC) or automotive air conditioning (AAC) systems is thermally modeled. The performance of mini-channel evaporator is also compared with the laminated evaporator which is being currently used in automotive industries. The mini-channel evaporator was constructed of two rows of parallel flow mini-channel tubes...

In the manufacturing of ammonium nitrate, a condensate containing ammonia and ammonium nitrate is obtained. The concentrations of these species are in practically all cases too high for direct discharge into a water recipient. At some plants, some of the dilute ammonium nitrate solution can be spread out on adjacent farmland, as it is a fertilizer, but commonly, nitric acid is added to this str...

Capacity and efficiency of any refrigerating system diminish rapidly as the difference between the evaporating and condensing temperature is increased by a reduction in the evaporator temperature. The single stage vapour compression refrigeration system using various refrigerants are limited to an evaporator temperature of -40 0C. Below temperature of -40 0C the either cascade refrigeration sys...

The use of constant pressure (automatic) expansion valves as the metering device in vapor compression refrigeration cycles employed in air conditioning systems offer functional advantages which result in first cost and operating cost benefits to the manufacturers and users of air conditioning equipment. Operating performance is improved at typical application air temperature conditions and powe...

Capacity and efficiency of any refrigerating system diminish rapidly as the difference between the evaporating and condensing temperature is increased by reduction in the evaporator temperature. The single stage vapour compression refrigeration system is limited to an evaporator temperature of -40 C. Below temperature of -40 C the either cascade refrigeration system or multi stage vapour compre...

thermal modeling of an automotive cabin was performed in this paper to predict the inside cabin air temperature. to implement this task, thermal and ventilation loads were estimated and the mass and energy balance conservation equations for dry air and water vapor with considering a new parameter (air circulation ratio) as well as the balance equations of internal components of a cabin were der...

This study investigated experimentally and theoretically, how condensate and initial formation of a thin frost layer on the surface of the evaporator affects the evaporator performance of room air-conditioners compared to dry coil conditions. The theoretically obtained results were validated with the measured values in both wet and initial frost formation conditions and a good correlation was f...

A fully equipped automotive air-conditioning test system consists of 5 main components: a compressor, a condenser, an orifice tube, an evaporator and an accumulator. R-134a is used as refrigerant. The coefficient of performance, evaporator cooling capacity, compressor power consumption, total mass flow rate, vapor mass flow rate, liquid mass flow rate and oil in circulation, pressures and tempe...