Turbulent Combustion (turbulent + combustion)

Distribution by Scientific Domains


Selected Abstracts


PIV measurement and turbulence scale in turbulent combustion

HEAT TRANSFER - ASIAN RESEARCH (FORMERLY HEAT TRANSFER-JAPANESE RESEARCH), Issue 7 2006
Kazuhiro Yamamoto
Abstract We have investigated turbulent combustion by PIV (Particle Image Velocimetry) technique. Comparing with LDV data, the validity of PIV measurements has been confirmed. Particularly, the conditions of sampling number and spatial resolution have been shown to yield reliable data using PIV. Based on the velocity fields in cold flow and combustion, the interaction between flame and flow has been discussed. It was observed that the flow field is changed by combustion and the turbulence is reduced. In order to determine statistical quantities such as mean velocity and RMS of velocity fluctuation, a sampling number of 1000 is needed. Moreover, the velocity correlation coefficient was evaluated to obtain the integral length scale of the flow. For both cold flow and combustion, the PIV estimated scale is very close to that of LDV based on the assumption of Taylor's hypothesis. As a result, the spatial resolution in this study is about 6 times smaller than the integral length scale. © 2006 Wiley Periodicals, Inc. Heat Trans Asian Res, 35(7): 501,512, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/htj.20129 [source]


RANS-simulation of premixed turbulent combustion using the level set approach

PROCEEDINGS IN APPLIED MATHEMATICS & MECHANICS, Issue 1 2005
A. Kurenkov
A model for premixed turbulent combustion is investigated using a RANS-approach. The evolution of the flame front is described with the help of the level set approach [1] which is used for tracking of propagating interfaces in free-surface flows, geodesics, grid generation and combustion. The fluid properties are conditioned on the flame front position using a burntunburnt probability function across the flame front. Computations are performed using the code FASTEST-3D which is a flow solver for a non-orthogonal, block-structured grid. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]


Combustion modeling of blended coal in a 300-MW tangentially fired boiler using a two-mixture-fraction model

ASIA-PACIFIC JOURNAL OF CHEMICAL ENGINEERING, Issue 4 2009
Qing-Yan Fang
Abstract The combustion process in a 300-MW tangentially fired boiler furnace fired with a blended coal has been numerically simulated. The blended coal contains a low-quality bituminous coal and anthracite and it was injected into the furnace from different burner nozzles. In order to better capture the combustion characteristics, a two-mixture-fraction model has been developed to model the combustion process of each individual coal of the blend. The two mixture fractions were used to separately track the combustion processes of the two component coals to reveal the effect of the combustion of the two coals on the chemical reactions in local zones of the furnace. The sum of the two mixture fractions was used to calculate the gas-phase turbulent combustion. Temperature measurements in the furnace were carried out by a flame image processing technique for model validation. Simulation results show that the temperature and oxygen concentration on the horizontal cross-sections close to the primary air burner nozzles in the furnace are nonuniformly, but symmetrically distributed across the four corners. The temperatures predicted by the simulation agree well with those measured by the flame image processing technique with a maximum error of 8.65%. Copyright © 2009 Curtin University of Technology and John Wiley & Sons, Ltd. [source]