• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Combustion Science and Technology >Effect of buoyancy on dynamical responses of coflow diffusion flame under low-frequency alternating current
【24h】

Effect of buoyancy on dynamical responses of coflow diffusion flame under low-frequency alternating current

机译：低频交流电下浮力对同流扩散火焰动力响应的影响

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

The dynamical responses of a small coflow diffusion flame to low-frequency alternating current (AC) were investigated under voltages (V-ac) and frequencies (f(ac)) in the range of 0-5kV and of 0-200Hz, respectively. As high voltages were applied to the fuel nozzle, a frequency-multiplication mode was identified from the flame oscillations at f(ac)8Hz using high-speed imaging. This mode was characterized by bulk flame oscillations at multiples of f(ac) until f(ac)=12Hz, close to the frequency of the natural buoyancy-driven oscillation with the burner configuration used in this study. As f(ac) increased past 12Hz, the bulk flame oscillated at f(ac), resulting in a lock-in' mode. The results of experiments using a counterflow diffusion flame configuration with negligible buoyancy confirmed that it was the coupling between buoyancy-driven flows and AC-driven ionic winds that caused the frequency-multiplication phenomenon. For f(ac)32Hz, the bulk flame ceased to oscillate, and a spectral analysis found that ionic winds dominated the dynamic flame responses. The distinctions between AC forcing and acoustic forcing were highlighted. Particle image velocimetry (PIV) experiments at a kHz repetition rate were conducted to reveal the time-resolved flow fields. Electrical diagnostics captured the electrical signals; the calculated power consumption of the applied AC, with respect to the flame-heating power, was about 10(-6).
机译：分别在0-5kV和0-200Hz的电压（V-ac）和频率（f（ac））下研究了小型同流扩散火焰对低频交流电（AC）的动力响应。当向燃料喷嘴施加高电压时，使用高速成像从f（ac）<8Hz的火焰振荡中识别出倍频模式。这种模式的特征是火焰在f（ac）的倍数处振荡，直到f（ac）= 12Hz，接近本研究中使用的燃烧器配置的自然浮力驱动振荡的频率。当f（ac）增加到超过12Hz时，大块火焰在f（ac）处振荡，从而导致锁定模式。使用浮力可忽略不计的逆流扩散火焰构型进行的实验结果证实，是由浮力驱动的气流和交流电驱动的离子风之间的耦合引起了倍频现象。当f（ac）> 32Hz时，大块火焰停止振荡，光谱分析发现离子风主导了动态火焰响应。强调了交流强迫和声学强迫之间的区别。进行了以kHz重复频率进行的粒子图像测速（PIV）实验，以揭示时间分辨的流场。电气诊断程序捕获了电信号；相对于火焰加热功率，所计算的交流电的功耗约为10（-6）。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号