EXPERIMENTAL RESEARCH OF THE GAS COMPRESSION CHAMBER THERMAL REGIME OF THE COMPUTER EFFUSION DECREASING DISCHARGE PRESSURE GAS DENSITY ANALYZER

The article presents the results of checking mathematical model of the created decreasing pressure effusion computer gas density analyzer. Operating principle of a decreasing pressure effusion gas density analyzers is based on measuring the outflow time of the analyzed gas certain volume through a microdiaphragm. A generalized scheme of such analyzers and their operation are described in article. Initial equations of the mathematical model, the assumptions and the results of the development of the mathematical model are presented. The created experimental setup for testing the developed mathematical model and its operation also are described. The mathematical model was tested in the course of numerous experiments on this facility for a number of gases. Studies have also been performed to assess the effect of temperature on the measurement result. The results of the mathematical model test are presented in the article. The results of experimental studies were compared with the calculated data obtained on the basis of a mathematical model. As a result, the error of the mathematical model of the decreasing pressure effusion gas density analyzers was determined and conclusions were made about its adequacy and possible further use for designing and calculating decreasing pressure effusion gas density analyzers.

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Gas Turbine Driven Centrifugal Compressors for Gas Storage and Withdrawal Applications

Volume 3: Coal, Biomass and Alternative Fuels; Combustion and Fuels; Oil and Gas Applications; Cycle Innovations ◽

10.1115/86-gt-112 ◽

1986 ◽

Author(s):

Horst Hornberger ◽

Albrecht Wockenfuss ◽

Klaus D. Schmidt

Keyword(s):

High Reliability ◽

Gas Storage ◽

Primary Energy ◽

Gas Compression ◽

Wide Range ◽

Winter Time ◽

Discharge Pressure ◽

Summer Time ◽

Gas Fields ◽

Gas Supply

The increasing acceptance of natural gas as primary energy in different market segments and the variance in consumption between the seasons require more and more buffer storage capacity, because of contracted constant gas supply quantities. The surplus gas becoming available during the summer time can be stored and withdrawn during the winter time for covering peak demands. Based on these facts, the gas distribution companies utilize exploited gas fields for gas storage by drilling additional wells and installing gas compression facilities. Such a compression duty with a wide range in flow and discharge pressure requires a great flexibility of the compression equipment, including high reliability and availability during operation periods.

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Numerical Modeling and Simulation of Injection Cooling and Wet Gas Compression

ASME 2016 Power Conference ◽

10.1115/power2016-59400 ◽

2016 ◽

Author(s):

Shyam Kishor

Keyword(s):

Droplet Size Distribution ◽

Droplet Breakup ◽

Heat Transfer Analysis ◽

Droplet Dynamics ◽

Wet Gas ◽

Gas Compression ◽

Compression Cycle ◽

Transient Simulations ◽

Compressible Turbulent Flow ◽

Compression Chamber

This paper presents application of Computational Fluid Dynamics (CFD) in modeling wet gas compression in a multiphase compressor, where liquid is injected inside the compression chamber to enhance cooling and achieve near isothermal compression. CFD is used for detailed flow field and heat transfer analysis. It includes 3D transient simulations of multiphase compressible turbulent flow. During each cycle, compression and suction chambers keep moving and deforming. Computational domains include a gate that separates compression chamber from the suction chamber. Gate moves up and down to always remain in contact with the rotor. A custom program is used to prescribe motion for the moving and deforming domain. Eulerian-Lagrangian method is used to model continuous and discrete (atomized droplets) phases and their interaction. Droplet dynamics under the influence of turbulence, acceleration, diffusion and body forces are studied. Models to capture droplet breakup and coalescence are included. Results from CFD simulations are used to optimize compressor performance. Temperature and pressure variations during the compression cycle are presented. Most of the pressure and temperature rise occurs towards the end of the compression cycle. Atomization details including droplets trajectory, droplet size distribution and droplet velocity variations are presented. Temperature distribution inside the compression chamber is used to optimize location, size, and flow rate of liquid injections.

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Secondary Transfer Effect of Contact

Social Psychology ◽

10.1027/1864-9335.40.2.55 ◽

2009 ◽

Vol 40 (2) ◽

pp. 55-65 ◽

Cited By ~ 146

Author(s):

Thomas F. Pettigrew

Keyword(s):

Cognitive Dissonance ◽

Experimental Research ◽

Intergroup Contact ◽

Transfer Effect ◽

Evaluative Conditioning ◽

Transfer Effects ◽

Secondary Transfer ◽

Primary Reduction

This paper reviews the evidence for a secondary transfer effect of intergroup contact. Following a contact’s typical primary reduction in prejudice toward the outgroup involved in the contact, this effect involves a further, secondary reduction in prejudice toward noninvolved outgroups. Employing longitudinal German probability samples, we found that significant secondary transfer effects of intergroup contact exist, but they were limited to specific outgroups that are similar to the contacted outgroup in perceived stereotypes, status or stigma. Since the contact-prejudice link is bidirectional, the effect is inflated when prior prejudice reducing contact is not controlled. The strongest evidence derives from experimental research. Both cognitive (dissonance) and affective (evaluative conditioning) explanations for the effect are offered.

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