Computation of Turbulent Flows in Natural Gas Pipes with Different Rectifiers

Abstract:

With the development of natural gas industry, improving the accuracy of the flowmeter systems is becoming the common concerned problem both corporations and customers. Many experiments demonstrate that the different flow field structures in pipes with diverse baffle installations have great influence on the measure accuracy of flowmeters. In order to measure the flux in pipes more accurate, the flowmeters must be installed downstream the baffles far away so that the irregular flows induced by baffles have less influence on the flowmeters. However, the installation lengths downstream baffles for flowmeters in ISO are are usually much longer than the allowable lengths for the local flowmeters. To decrease the installation lengths and loss measure accuracy of flowmeters as little as possible, it is necessary to study the flows in pipes with baffles. CFD is a good tool for the study. Here, the flows in a diffusive pipe with various rectifiers are computed as examples. The lengths of the irregular flows induced by the diffuser and rectifier are shown. By analyzing and comparison the numerical results, the installation lengths for flowmeters and the rectification of the different rectifiers are confirmed. The study conclusions will be very useful for guiding the local flowmeter selection and installation in the future.

• Periodical: Advanced Materials Research (Volumes 455-456)
• Pages: 344-350
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.455-456.344
• Online since: January 2012
• Authors: Z.H. Xiong, Zhen Lin Li
• Keywords: Computational Fluid Dynamics (CFD), Diffusive Pipe, Flowmeter, Natural Gas Measurement, Rectifier

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