Horizontal well performance is typically estimated using a steady-state productivity index equation similar to Joshi's productivity index, which assumes constant wellbore pressure. The wellbore pressure in a horizontal well is not constant, and the pressure drop in the horizontal section can approach the reservoir drawdown. This paper presents a new model to estimate horizontal well productivity by incorporating wellbore hydraulics. The model is implemented in a program and calculates the well pressure throughout the length of the wellbore. The method reproduces the experimental results of two authors.

Keywords:
horizontal well, reservoir surveillance, dimensionless length, directional drilling, friction factor, production monitoring, permeability, new method, production control, reservoir drawdown
Subjects:
Drilling Operations, Well & Reservoir Surveillance and Monitoring, Formation Evaluation & Management, Directional drilling
Copyright 2005, Society of Petroleum Engineers
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