Streamline numerical well-testing interpretation model and pressure response for partially perforated wells

Abstract

A streamline numerical well-testing interpretation model for partially perforated wells was established that includes a filtration mathematical model of production period and a streamline mathematical model of testing period. Pressure response characteristic curves for partial perforated wells were obtained by solving the models of the two periods using streamline method and finite difference method, respectively. Pressure response characteristics for partially perforated wells were obtained by analyzing synthetically the streamline distribution and the pressure response characteristic curves. Two horizontal straight line segments will emerge in the derivative curve. The influence of permeability ratio, perforation thickness ratio and perforation location on pressure response was investigated. The larger the permeability ratio is, the earlier the second horizontal straight line segment will emerge. The less the perforation thickness ratio is, the greater the distance between the two horizontal straight line segments will be. The impact of perforation location on pressure response is little. Permeability ratio and perforation thickness ratio have significant effects on the pressure response and they must be taken into account in well-testing interpretation for partially perforated wells. Key words: partial perforation, numerical well-testing, interpretation model, streamline distribution, pressure response