Skip to main content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

TESTING LONG-WAVELENGTH ACOUSTIC FLOWMETER CONCEPTS FOR FLUE GAS FLOWS

Published

Author(s)

Lee J. Gorny, Keith A. Gillis, Michael R. Moldover

Abstract

As a part of NIST’s program to standardize measurements of greenhouse gas emissions, we are developing a long-wavelength acoustic flowmeter (LWAF) for accurate, economical measurements of exhaust flows from coal-burning power plants. Measurements of the flue gas mass flowrate combined with the gas’s composition are used to determine the emitted CO2 and other by-products of combustion. Today, such measurements have uncertainties of 5% or more due to the large size of the flue-gas stacks and the flow’s non-uniform, unsteady, and swirling profile. A LWAF averages the spatial non-uniformities of the axial velocity over the entire cross section in a manner insensitive to flow distortions. In contrast, conventional techniques measure gas flow only at isolated points or averaged along chord across the stack. We constructed a 1:100 scale, calibrated flow facility for the initial development of a LWAF. In preliminary tests of three flow metering methods, uncertainties ranged from 1.4% to 4.9%, compared to our target uncertainty of 1%. We present the principle behind the LWAF, our design considerations, and the current performance of time and frequency-based approaches to metering, and describe technical challenges that must be overcome to use a LWAF at a full-scale power plant.
Proceedings Title
8th International Symposium on Fluid Flow Measurement
Conference Dates
June 18-22, 2012
Conference Location
Colorado Springs, CO

Keywords

flow meter, acoustic, long-wavelength, calibration, frequency response function, sound propagation, greenhouse gas, power plant, emissions, flue gas
Created June 22, 2012, Updated February 19, 2017