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...

A fuzzy logic controller of the heat recovery systems of cement clinker grate cooler is presented in this paper. The development and tests of the proposed fuzzy controller have been implemented in a cement plant in Guangdong, China. Cooling is performed by blowing fresh air underneath the grate cooler plate and heat recovery is obtained by outlet pipe extracting the hot air. However, continuous...

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...

Purpose: The purpose of this study was to investigate the effects of two air-abrasive prophylaxis systems and the effect of inlet air pressure on the surface of Brhnemark titanium abutment cylinders. Materials and Methods: Single abutment cylinders were treated with either the Prophy-Jet system (sodium bicarbonate abrasive) (Dentsply International, York, PA) or the Microprophy system (aluminum ...

Computational fluid dynamics (CFD) is potentially a valuable tool for simulating the dispersion of air contaminants in workrooms. However, CFD-estimated airflow and contaminant concentration patterns have not always shown good agreement with experimental results. Thus, understanding the factors affecting the accuracy of such simulations is critical for their successful application in occupation...

The present paper aims to study the effect of cooling air inlet methods on gas turbine compressors increasing their efficiency. After modeling cycles with absorption and compression systems in EES software, these cycles' performance is investigated for all equipment cycle from thermodynamic, exergy, exergoeconomic aspects. In system, conventional solution lithium bromide-water used as a two-com...

A wind tunnel conditions the air flow for testing equipment, such as heat exchangers, over a wide range of conditions. In this paper, a procedure to develop the operating envelope for the tested equipment in a wind tunnel is presented. The temperature and humidity of the air that requires conditioning is controlled and maintained by the combination of cooling coil (or evaporator), heating eleme...

In traditional raised-floor data center design with hot aisle and cold aisle separation, the cooling efficiency suffers from recirculation resulting from the mixing of cool air from the Computer Room Air Conditioning (CRAC) units and the hot exhaust air exiting from the back of the server racks. To minimize recirculation and hence increase cooling efficiency, hot aisle containment has been empl...