【摘要】 Sisko流变模式能够准确地描述钻井液流变性,基于广义流性指数给出了该模式水力计算模型。根据RabinowitshMooney方程给出了其管流流量方程,同时基于槽流模型给出了其同心环空流量表达式。根据管流特性参数,引入Reed与Pilehvari定义的管流有效管径,将其扩展应用到环空,定义了适用于该流体的新环空广义流性指数及有效管径。通过有效管径将Sisko流体管内、环空流动与牛顿流体管流流动相关联。通过理论推导给出了广义雷诺数表达式,该式不以广义流性指数是常数为前提,进而给出了流态判别模型,建立了统一的压耗计算模型,得到了适用于该模型的水力计算方法。通过与多组已公开发表的实验数据对比,运用该方法计算的压耗与实测数据吻合很好;说明运用此模型能够很好地预测非牛顿流体管内及环空流动压耗。更多还原

【Abstract】 The Sisko rheological model can give a better description of the rheological characteristics of drilling fluid. Its hydraulic calculation model based on the generalized flow behavior index method is obtained. Based on the Rabinowitsch-Mooney equation,the equation between the wall shear stress and volumetric flow rate of this model for pipe was obtained. And modeled as a slot,the equation for annular flow was obtained too. Quoting the pipe effective diameter which Reed and Pilehvari proposed and expanding it to annular flow analysis,a new generalized flow behavior index and effective diameter for annular flow of this rheological model were defined. The generalized effective diameter was independent on the assumption that n’ is constant. And then the flow regime method was established by quoting n’ and a utility pressure loss calculation method was obtained. The hydraulic calculation method was compared with several sets of experimental hydraulics data from different sources. The comparisons of pressure loss show excellent agreement over laminar and turbulent of different type fluid in pipe and annulus. The results show that this method can precisely calculate and predict the pressure loss of non-Newtonian fluid in pipe and annulus.更多还原