| With the development of aerospace technology, the attention of researchers isincreasingly concentrated to the burning issue in microgravity and body-force field insteadof earth gravity. Given this, it is a great opportunity to develop isothermal combustion andnew engines. In this paper computational fluid dynamics and experimental method areapplied to investigate the stability of premixed flames in body-force field.Two-dimensional axisymmetric numerical model is established using the FLUENTand combustion in one-way force field is investigated. Temperature distribution, flow field,chemical reaction and the extinction of premixed flames are investigated under differentbody-force fields. The result shows that flames are greatly affected by the body-force.When the body-force is in the opposite direction of the gas flow, flames are more likely tobe stable.Three-dimensional premixed combustion numerical model is established in thecentrifugal field. When the jet velocity and centrifugal force is in the same direction, thestability of premixed flames is investigated under the influence of centrifugal and coriolisforce. In order to capture the flame and control the grid numbers, the mesh adaption is used.It is found that the flames extend along the direction of the body-force and the angles offlame deflection increase with the increase of rotational speed sectionally. Affected by thecoriolis force, the flame deflects, and are more likely to be unstable. It’s also obtained thatthe quenching process and the flame’s extinction under various equivalent ratios andvarious inlet velocities, and then compared them with the experimental data.In the end, using the method of experiment, the stability of the flames is studied. Theflame flickering motions are analyzed under different rotational speeds, inlet velocities, jetangles and equivalent ratios. The flickering frequency is about1.05—1.38and greater thanrotational frequency. So further studies on flame flickering motions are needed. |
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