Computational fluid dynamics analysis of a wire-feed, high-velocity oxygen fuel (HVOF) thermal spray torch
Computational fluid dynamics analysis of a wire-feed, high-velocity oxygen fuel (HVOF) thermal spray torch
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送丝高速氧燃料 (HVOF) 热喷涂炬的计算流体动力学分析
DOI：
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发表时间：
1996
期刊：
影响因子：
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通讯作者：
T. Roemer
中科院分区：
文献类型：
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作者：
A. R. López;B. Hassan;W. Oberkampf;R. Neiser;T. Roemer
采用计算和实验相结合的方法，对超音速火焰（HVOF）热喷涂喷枪的流体动力学和颗粒动力学进行了分析。三维计算流体动力学（CFD）的结果，用于涂层内表面，如发动机气缸孔弯曲的空气帽。所分析的装置类似于美科金刚石射流旋转丝（DJRW）焊炬。原料气通过轴对称喷嘴喷入弯曲气帽。预混合的丙烯和氧气从喷嘴中的环形空间引入，而冷却空气在喷嘴和气帽的内壁之间注入。燃烧过程采用单步有限速率化学模型，共包含9种气体，其中包括燃烧产物的分解。一根连续喂入的钢丝穿过喷嘴的中心，在靠近气帽出口的圆锥形尖端处发生熔化。通过将液态钢颗粒注入到靠近焊丝尖端的流场中，对焊丝熔化进行了数值模拟。还采用激光双焦点（L2F）测速系统进行了送丝过程中的实验粒子速度测量。空气帽内外的流场，并与空气帽外的实验测量的颗粒速度的预测进行了比较。
The fluid and particle dynamics of a high-velocity oxygen fuel (HVOF) thermal spray torch are analyzed using computational and experimental techniques. Three-dimensional computational fluid dynamics (CFD) results are presented for a curved aircap used for coating interior surfaces such as engine cylinder bores. The device analyzed is similar to the Metco diamond jet rotating wire (DJRW) torch. The feed gases are injected through an axisymmetric nozzle into the curved aircap. Premixed propylene and oxygen are introduced from an annulus in the nozzle, while cooling air is injected between the nozzle and the interior wall of the aircap. The combustion process is modeled using a single-step, finite-rate chemistry model with a total of nine gas species which includes dissociation of combustion products. A continually fed steel wire passes through the center of the nozzle, and melting occurs at a conical tip near the exit of the aircap. Wire melting is simulated computationally by injecting liquid steel particles into the flow field near the tip of the wire. Experimental particle velocity measurements during wire feed were also taken using a laser two-focus (L2F) velocimeter system. Flow fields inside and outside the aircap are presented, and particle velocity predictions are compared with experimental measurements outside of the aircap.