含空心球钻井液分离流场数值模拟

Numerical simulation of separation flow field of drilling fluid with hollow glass spheres

为分析常规旋流分离器在深水含空心球钻井液双梯度钻井中分离回收空心球的可行性,建立了旋流器中分离场的RNGκ-ε湍流数学模型。利用计算流体动力学模拟给定工况下旋流分离过程,分析了旋流器内部压力场、速度分布特征及分离效率,岩屑的分离效率为78.99%,空心球回收分离效率达95.75%。结果表明在深水空心球双梯度钻井中采用常规旋流分离器回收钻井液中空心球可行,同时为改进结构设计、提高分离性能和降低能量损耗提供了一定依据。

In order to analyze the feasibility of recycling hollow glass spheres(HGS)in deepwater HGS Dual Gradient Drilling(DGD)by using conventional oilfield hydrocyclone,the RNG k-ε mathematic model of turbulent flow is established to express the turbulence field distribution of hydrocyclone,and the computational fluid dynamics is utilized to simulate the separation of hydrcyclone under a certain condition.The pressure field,the velocity distribution and the separation efficiency of hydrocyclone are analyzed.The separation efficiency of debris is 78.99% and the HGS recycling efficiency can reach 95.75%.The results show that conventional oilfield hydrocyclone can be used in deepwater HGS DGD,which provides a certain basis for improvement of the structure design and the performance,and reduction of the energy loss of hydrocyclone.