Gas compressor

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

Experimental Investigation of Centrifugal Compressor Stabilization Techniques

Abstract: Results from a series of experiments to investigate techniques for extending the stable flow range of a centrifugal compressor are reported. The research was conducted in a high-speed centrifugal compressor at the NASA Glenn Research Center. The stabilizing effect of steadily flowing air-streams injected into the vaneless region of a vane-island diffuser through the shroud surface is described. Parametric variations of injection angle, injection flow rate, number of injectors, injector spacing, and injection versus bleed were investigated for a range of impeller speeds and tip clearances. Both the compressor discharge and an external source were used for the injection air supply. The stabilizing effect of flow obstructions created by tubes that were inserted into the diffuser vaneless space through the shroud was also investigated. Tube immersion into the vaneless space was varied in the flow obstruction experiments. Results from testing done at impeller design speed and tip clearance are presented. Surge margin improved by 1.7 points using injection air that was supplied from within the compressor. Externally supplied injection air was used to return the compressor to stable operation after being throttled into surge. The tubes, which were capped to prevent mass flux, provided 9.3 points of additional surge margin over the baseline surge margin of 11.7 points.

Power conversion system utilizing reversible energy of liquefied natural gas

Abstract: A power conversion system comprising a combination of a liquefied natural gas vaporizing plant and a fuel burning power generating facility is disclosed. The liquefied natural gas vaporizing plant utilizes the cryogenic capacity of the liquefied natural gas to produce liquid air which is pumped to a high pressure by a liquid air pump. The liquid air is then brought into a heat exchanging relationship with air drawn into the vaporizing plant so that the high pressure liquid air is converted to high pressure gaseous air. The high pressure gaseous air which represents recovered reversible energy of the liquefied natural gas is fed into a combustion chamber of the fuel burning power generating plant. Since the power generating facility requires no significant output of power to drive a compressor to compress ambient air prior to its entry into the combustion chamber, the power generating facility is operated at a high efficiency.

Turbocharged exhaust gas recirculation system

Abstract: An exhaust recirculation system includes a power source including at least one cylinder outputting exhaust gas and a particulate reducing device fluidly connected to at least one exhaust duct of the power source. The particulate reducing device is configured to reduce an amount of particulates in the exhaust gas. The exhaust recirculation system also includes a recirculation compressor configured to receive and compress at least a portion of the exhaust gas. An intake duct of the at least one cylinder of the power source is fluidly connected to the recirculation compressor to receive the compressed reduced-particulate exhaust gas.

Capacity-controlled ground source heat pumps in hydronic heating systems

Abstract: The objective of this study was to investigate the energy-saving potential of using variable-speed capacity control instead of the conventional intermittent operation mode for domestic ground source heat pumps. Variable-speed capacity control is commonly used in air-to-air heat pumps, but not in ground source heat pumps for hydronic heating systems, even though the energy-saving potential may be greater for this application. A theoretical analysis indicates how the energy efficiency is influenced by variable-speed capacity control of the compressor. The analysis shows that, to take full advantage of the capacity control, care should be taken to achieve the correct relationship between refrigerant flow and heat transfer media flows. Intermittent control and variable-speed capacity control were compared by laboratory tests on two capacity-controlled heat pumps and one standard heat pump with a single-speed compressor. Test data were then used for seasonal performance factor (SPF) calculations. The SPF calculations show that despite improved performance at part load the variable-speed controlled heat pump did not improve the annual efficiency compared to the intermittently operated heat pump. This is mainly due to inverter and compressor motor efficiencies and the need for improved efficiency and control of pumps used in the heating and ground collector systems.

Subsea compression system and method

Abstract: A subsea compression system and method wherein a wellstream fluid is flowed through a flow line (12) from a reservoir (10) and into a separation vessel (16) for subsequent compression in a compressor (18; 18', 18") prior to export of gas. A recycle line (24; 24', 24") is fluidly connected at a first end to the compressed wellstream at the outlet side of the compressor (18; 18', 18") and at a second end to the wellstream at a location between the separation vessel (16) and the inlet side of the compressor (18; 18', 18"), said recycle line being capable of controllably (32) feeding fluid due to surge back to the compressor inlet side and avoiding the need to feed said fluid into the separation vessel, because the re-circulated gas is dry both due to having been separated at seawater temperature, and then being heated during recirculation.