Effect of confinement (wall proximity) of a confined impinging jet reactor (CIJR) on the flow field, residence time distribution and heat transfer are explored, through experiments and CFD simulations. Hydrodynamic characteristics are evaluated for different parameters namely confinement, impinging jet velocity, temperature gradient, and so on. For 2 mm confinement, highest values of dispersion number and overall heat transfer coefficient are observed due to interaction of turbulent eddies followed by the effect of reactor wall proximity. For the CIJR having confinements above 10 mm, jet velocity need to be greater than 3 m/s to achieve both, excellent mixing efficiency and high heat removal rate. Empirical correlations for Dispersion and Nusselt numbers as a function of Re_j and L/D are obtained, over a range of $500\le {\mathit{Re}}_j\le 3000$ and $5\le L/D\le 35$, which correspond to jet velocity of 0.5–3 m/s. The present study gives a basis for designing CIJR suitable for rapid, homogeneous, exothermic reactions.

中文翻译：

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评估受限冲击射流反应器对放热反应的适用性：流体动力学、停留时间分布和传热

通过实验和 CFD 模拟，探讨了受限冲击射流反应器 (CIJR) 的约束（壁面接近度）对流场、停留时间分布和传热的影响。评估不同参数的流体动力学特性，即约束、冲击射流速度、温度梯度等。对于 2 mm 的限制，由于湍流涡流的相互作用以及反应器壁接近度的影响，观察到分散数和总传热系数的最高值。对于限制在 10 mm 以上的 CIJR，射流速度需要大于 3 m/s 才能同时实现出色的混合效率和高热去除率。作为Re _j和L/D函数的色散数和努塞尔数的经验相关性获得，在一个范围内$500\le {\mathit{回覆}}_j\le 3000$和$5\le \mathrm{大号}/D\le 35$，对应于 0.5-3 m/s 的射流速度。本研究为设计适用于快速、均相、放热反应的 CIJR 提供了基础。