Gas compressor

About: Gas compressor is a research topic. Over the lifetime, 91817 publications have been published within this topic receiving 552209 citations.

Extracted, cooled, compressed/intercooled, cooling/combustion air for a gas turbine engine

Abstract: A system for cooling hot section components of a gas turbine engine. The cooling system includes a plurality of compressors, or compression train, and an intercooler disposed between each adjacent pair of compressors so as to achieve the desired pressure and temperature of the cooling air at reduced shaft power requirements. The first stage of compression may be provided by the booster, or low pressure compressor, of the engine, with the first intercooler receiving all of the air discharging from the booster. After exiting the first intercooler, a first portion of the booster discharge air is routed to the engine high pressure compressor and a second portion is routed to an inlet of the second compressor of the cooling air compression train. The compressed, cooled air exiting the last, downstream one of the compressors is used for cooling at least a first hot section component of the engine.

Refrigeration cycle device

Abstract: PROBLEM TO BE SOLVED: To provide a refrigeration cycle device capable of preventing oil from becoming biased when a first compressor and a second compressor are connected in series in a refrigerant circuit SOLUTION: This refrigeration cycle device is provided with the first compressor 37, the second compressor 54 connected with the first compressor in series in the refrigerant circuit, and oil separators 31, 45 provided on refrigerant discharge sides of each compressor 37, 54, respectively Each oil separator 31, 45 is provided with a flow-out hole 72 for letting oil flow out into the refrigerant circuit when oil level reaches specified amount COPYRIGHT: (C)2004,JPO&NCIPI

Fuzzy control of the compressor speed in a refrigeration plant

Abstract: In this paper, referring to a vapor compression refrigeration plant subjected to a commercially available cold store, a control algorithm, based on the fuzzy logic and able to select the most suitable compressor speed in function of the cold store air temperature, is presented. The main aim is to evaluate the energy saving obtainable when the fuzzy algorithm, which continuously regulates the compressor speed by an inverter, is employed to control the compressor refrigeration capacity instead of the classical thermostatic control, which imposes on/off cycles on the compressor that works at the nominal frequency of 50 Hz. The variation of the reciprocating compressor speed is obtained by controlling the compressor electric motor supply current frequency in the range 30–50 Hz, as it is not possible to consider values smaller than 30 Hz because of the lubrication troubles due to the splash system. In this range, two among the most suitable working fluids proposed for the R22 substitution, such as the R407C (R32/R125/R134a 23/25/52% in mass) and the R507 (R125/R143A 50/50% in mass) are tested. Comparing the compressor speed fuzzy control with the classical thermostatic control, frequently used in the cold stores and in other refrigeration systems, the experimental results show a meaningful energy saving equal even to about 13% when the R407C is used as a working fluid. In particular, to explain from the energy saving point of view the best performances of the refrigeration plant when the compressor speed varies, an exergetic analysis is realized. Besides, with regard to the inverter cost, the pay-back period determined is more than acceptable for the plant size examined.

Intercooled turbine blade cooling air feed system

Abstract: A gas turbine engine having a compressor and an air-cooled turbine is provided with a cooling system for decreasing the temperature of the turbine cooling air. A heat exchanger, mounted on the compressor casing, receives a portion of the pressurized air which is bled from the compressor. A heat sink medium is pumped through the heat exchanger into heat exchange relationship with the pressurized air, thereby cooling the air. The cooled air is then further pressurized and routed to and circulated through the turbine rotor blades to provide improved cooling thereof. The intercooling of the compressor bleed air permits a reduction in the quantity of compressor air required for turbine rotor blade cooling or allows an increase in turbine entry temperature and thus provides an improvement in engine power and performance. In the case where the heat sink medium is engine fuel, the heat extracted from the compressor bleed air is returned to the engine operating cycle in the form of heated engine fuel.

Energy, exergy and thermoeconomic analysis of a combined cooling, heating and power (CCHP) system with gas turbine prime mover

Abstract: In this paper energy, exergy and thermoeconomic analysis of a combined cooling, heating and power (CCHP) system has been performed. Applying the first and second laws of thermodynamics and economic analysis, simultaneously, has made a powerful tool for the analysis of energy systems such as CCHP systems. The system integrates air compressor, combustion chamber, gas turbine, dual pressure heat recovery steam generator (HRSG) and absorption chiller to produce cooling, heating and power. In fact, the first and second laws of thermodynamics are combined with thermoeconomic approaches. Next, computational analysis is performed to investigate the effects of below items on the fuel consumption, values of cooling, heating and net power output, the first and second laws efficiencies, exergy destruction in each of the components and total cost of the system. These items include the following: air compressor pressure ratio, turbine inlet temperature, pinch temperatures in dual pressure HRSG, pressure of steam that enters the generator of absorption chiller and process steam pressure. Decision makers may find the methodology explained in this paper very useful for comparison and selection of CCHP systems. Copyright © 2010 John Wiley & Sons, Ltd.