Journal of the Korean Society of Mineral and Energy Resources Engineers ISSN:2288-0291(Print) 2288-2790(Online) 한국자원공학회지

This study presents a PC-based analytical model on the basis of physical concept of a horizontal well in order to identify flow regimes and to conduct parametric investigation of the reservoir characteristics. The model is established by using uniform-flux model which assumes constant fluid inflow from reservoir to the horizontal well, and is able to describe both constant pressure and no-flow boundary conditions. In the analysis of pressure and pressure derivative curves, it is found that various flow regimes on the type curve were identified corresponding to reservoir characteristics as well as conditions of horizontal well. These type curves are differentiated by the existence of minimum point and behavior of curve shape. The parametric studies for horizontal well length, vertical location, formation thickness, and anisotropy have been conducted to analyze behavior of the type curves generated for the horizontal well. Through the investigations of the parametric analysis, specially in the aspect of effect of upper boundary condition, early time behavior of pressure derivative curve is almost the same regardless of upper boundary conditions. Therefore, it is essential to test sufficiently long time to acquire later time data including the boundary effect in order to correctly characterize upper boundary condition of the reservoir.