缝隙喷嘴结构参数对射流扩散性影响规律研究

Slot Nozzle Spraying Diffusivity Affecting Law of the Nozzle Structural Parameters

超快速冷却过程中冷却水与空气发生卷吸作用使得冷却水扩散,喷嘴射流扩散性可使冷却水对钢板的冲击力产生明显的影响,进而影响到板带钢的冷却速率。针对常用的缝隙喷嘴结构采用有限体积法研究结构参数对喷嘴射流扩散性的影响规律,对计算结果进行对比分析得到以下规律:缝隙喷嘴的收缩角和总长度可对射流扩散性产生明显的影响,在缝隙喷嘴射流扩散性较低时喷嘴的收缩角为20°~30°,喷嘴总长度为20mm左右。以上研究结果对喷嘴结构设计及选型可提供重要参考。

The cooling water with high pressure can penetrate through the residual water layer and water film on top of the hot strip by the slot nozzle jet impingement,and then the ultra fast cooling can be achieved. Cooling water will be diffused after it was sprayed into the atmosphere by the entrainment effect and the kinetic energy of the cooling water will be decreased by the spraying diffusivity. So the spraying diffusivity can affect the cooling capacity. In-depth research on slot nozzle spraying diffusivity affecting law of nozzle structural parameters was conducted by the finite volume method,and some conclusions were obtained by analysis： slot nozzle shrinking angle and the total length can affect spray diffusivity obviously; the shrinking angle was 20° ~ 30° and the total length was about 20 mm.The results will provide important reference for slot nozzle design or nozzle selection.