Numerical Studies of the Application of Shock Tube Technology for Cold Gas Dynamic Spray Process
Numerical Studies of the Application of Shock Tube Technology for Cold Gas Dynamic Spray Process
复制标题
激波管技术在冷气动态喷涂过程中应用的数值研究
DOI：
10.1007/s11666-007-9123-7
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发表时间：
2007
影响因子：
3.1
通讯作者：
X. Luo
中科院分区：
文献类型：
--
作者：
R. Nickel;K. Bobzin;E. Lugscheider;D. Parkot;W. Varava;H. Olivier;X. Luo
通过建模和仿真，与首次实验进行比较，从根本上研究了一种无燃烧喷涂的新方法。本文重点研究了由激波管端壁部分的激波反射产生的气体-粒子喷嘴流的数值模拟。为了研究该过程的物理基础，目前仅考虑单次射击操作。颗粒从喷嘴喉部下游喷射到超音速喷嘴流中。通过激光多普勒风速仪 (LDA) 进行的颗粒速度测量表明，直径 15 μm 的不锈钢颗粒的最大速度可达 1220 m/s。 CFD 代码（Fluent）首先通过与长拉瓦尔喷嘴中气体和气体颗粒流场的可用数值和实验数据进行比较来验证。良好的一致性意味着新的动态工艺概念在冷气涂层应用中具有巨大的潜力。然后研究了冲击波实验室（SWL）设计和实现的短拉瓦尔喷嘴中的流场。模拟了实验获得的停滞条件下的气流。表面工程研究所（IOT）计算了没有和有颗粒对气流影响的气体-颗粒流，并与实验进行了比较。还研究了注射参数对粒子速度的影响。
A new method for a combustion-free spraying is studied fundamentally by modeling and simulation in comparison with first experiments. The article focuses on the numerical simulation of the gas-particle nozzle flow, which is generated by the shock reflection at the end wall section of a shock tube. To study the physical fundamentals of this process, at present only a single shot operation is considered. The particles are injected downstream of the nozzle throat into a supersonic nozzle flow. The measurements of the particle velocity made by a laser Doppler anemometry (LDA) set up show that the maximum velocity amounts to 1220 m/s for stainless steel particles of 15 μm diameter. The CFD-Code (Fluent) is first verified by a comparison with available numerical and experimental data for gas and gas-particle flow fields in a long Laval-nozzle. The good agreement implied the great potential of the new dynamic process concept for cold-gas coating applications. Then the flow fields in the short Laval nozzle designed and realized by the Shock Wave Laboratory (SWL) are investigated. The gas flow for experimentally obtained stagnation conditions is simulated. The gas-particle flow without and with the influence of the particles on the gas flow is calculated by the Surface Engineering Institute (IOT) and compared with experiments. The influence of the injection parameters on the particle velocities is investigated, as well.