Mixing Control System Using Micro Nozzle of 3D Vortex Generator and Flame holder Aiming at High-Speed Diffusion Combustion

利用3D涡流发生器和火焰保持器的微喷嘴实现高速扩散燃烧的混合控制系统

• 批准号: 12450087
• 负责人: YOSHIDA Hideo
• 金额: $ 9.66万
• 依托单位: KYOTO UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 2000
• 资助国家: 日本
• 起止时间: 2000 至 2002
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-12450087/
• 关键词: combustion; high-speed diffusion combustion; flame holding; micro nozzle; mixing control

For combustors of microturbines, enhancement of flame holding and mixing in a high-speed flow is crucial to make the combustor compact and also realize isothermal expansion combustion. To this end, we propose a combined nozzle and flame holder with small dimensions. That is, in the downstream of relatively high-temperature gas flow, a micro object, the shape of which is similar to an angel fish, is introduced as a fuel injector: on the back side of the injector, intense turbulence is generated.In the experiment, first, we prepared a high-speed and high-temperature wind tunnel. The attained maximum velocity and temperature were 105m/s and 550℃, respectively. Secondly, V-type and U-type fuel injectors which are two or three times larger than the final ones were used to obtain fundamental mixing and flame holding characteristics; their length and width are 1.5mm and 1mm, respectively. The V-shaped injector shows higher flame holding performance than the U-shaped injector, which indicates the validity of an angel-fish type micro injector.On the other hand, to clarify the mixing mechanism on the back side of the micro injector in detail, a numerical calculation using k-e turbulence model was conducted varying the injector geometry, As a first step of the numerical analysis, a flow around backward facing step with concave wall was analyzed. It was found that for the case with the concave wall the streamwise length of a recirculation zone decreases. The velocity near the concave wall, where fuel-injection holes are installed, was about 1% of that of the main flow. These facts are preferable in terms of the mixing enhancement.From the experimental and theoretical studies during 2000-2002, we conclude that the high potential of the present micro fuel injector as a high-speed diffusion combustion has been confirmed. An actual application to a microturbine combustor is now in progress.

对于微涡轮机的战斗人员，高速流中火焰固定和混合的增强对于使作用者紧凑并实现等温膨胀混合物至关重要。为此，我们提出了一个相结合的喷嘴和火焰支架，上面有较小的尺寸。也就是说，在相对高温气体流动的下游中，一种微物体，其形状与天使鱼相似，是作为燃料喷油器引入的：在喷油器的背面，产生了强烈的湍流。首先，在实验中，我们准备了高速和高速度的风隧道。达到的最高速度和温度分别为105m/s和550℃。其次，V型和U型燃料注射器比最终的燃料大两到三倍，以获得基本的混合和火焰保持特性。它们的长度和宽度分别为1.5mm和1mm。 The V-shaped injector Shows higher flame holding performance than the U-shaped injector, which indicates the validity of an angel-fish type microinjector.On the other hand, to clarify the mixing mechanism on the back side of the microinjector in detail, a numerical calculation using k-e turbulence model was conducted varying the injector geometry, As a first step of the numerical analysis, a flow around backward facing step with concave wall被分析。已经发现，对于凹壁的情况，​​再循环区域的流向长度减小。安装燃油注射孔的凹墙附近的速度约为主流量的1％。这些事实是在混合增强方面首选的。从2000- 2002年的实验和理论研究中，我们包括当前微燃料注射器作为高速扩散混合物的高潜力。现在正在进行微涡轮机组织的实际应用。