【摘要】 基于对现有研究成果的分析，选用了应用最广泛的涡动粘性系数法中的ｋε模型对高速超高压射流辅助钻井钻头井底湍流流场进行了数值模拟，研究了高速超高压射流的结构特性和喷管内外流场的分布规律．模拟精度基本达到了工程技术要求．对高速超高压射流喷管内外（井底）湍流流场的全场数值模拟表明，高速超高压射流井底流场是由射流冲击区、漫流区、涡流区和返流区组成的，对于有较大锥形角的斜面或曲面内流道喷嘴，一般可不必考虑流体的压缩性影响（约为５％）．更多还原

【Abstract】 The numerical simulation for the ultra high pressure water jet in the well bottom flow is used to study the ultra high pressure jet characteristics (such as velocity, pressure distribution law). Based on the analysis of the present research results, the applicable k ε turbulent model is applied to simulate the turbulent flow field of the pipe of ultra high pressure water jet in the submerged condition and in the 3 D cylindrical body fitted coordinate system with the finite volume method and non uniform grids in the axial symmetry condition. The whole flow was simulated and the influence of the inflow velocity, nozzle steady length and the standoff distance on flow field was studied. The calculation results were obtained and analysed.更多还原