A comprehensive investigation of the pseudo-skin factor for partially completed vertical wells

作者：Farokhi Vahid^*; Gerami Shahab

来源：Journal of Geophysics and Engineering, 2012, 9(6): 642-654.

DOI：10.1088/1742-2132/9/6/642

• pseudo-skin factor
• partially-penetrated well
• analytical model
• numerical simulator
• open interval location
• restricted entry
• infinite conductivity

To prohibit gas and/or water coning, it is very common for wells to be completed over only a portion of their productive zone. Such a procedure causes an additional pressure drop, termed the pseudo-skin factor, which reduces the well productivity. In order to ascertain whether or not a partially penetrated well requires stimulation, one has to quantitatively determine the different components of the total skin. Hence, an accurate evaluation of the pseudo-skin factor as one of the main components of the total skin is critical. Many authors have employed different mathematics to find expressions for estimating the pseudo-skin factor, however, since a comprehensive investigation of the available models has not as yet been performed, the diversity of these expressions could be very confusing. This paper first aims to propose an analytical model which accurately estimates the pseudo-skin factor in a partially penetrated well. In model development, the impacts of anisotropy and the arbitrariness of the open interval location are all taken into account, and the model is validated against a numerical simulator (ECLIPSE). Its second aim is to take the results of the numerical simulator as the comparison basis, and make a comprehensive investigation of the available models to check their accuracy for estimating the pseudo-skin factor. The results of the investigation show that, in comparison to other methods, this proposed model, Streltsova%26apos;s method and that of Yeh and Reynolds, estimate the pseudo-skin factor favourably close to that obtained by the simulator.

• 出版日期2012-12