Prediction of gas–water relative permeability in tight rock from movable fluid distribution with nuclear magnetic resonance

The measurement of the relative permeability in tight rock is challenging due to its ultralow and time-consuming nature experiments. Studying movable unmovable fluid distribution establishing a reliable prediction model an urgent problem be solved. This paper used nuclear magnetic resonance (NMR) investigate water sandstone under different centrifugal forces. A new method for predicting gas–water established based on using capillary bundle model. results show that fluids strongly influenced by rock's pore size structure. saturation increases as median radius decrease. nonlinear correlation between NMR relaxation time throat obtained from high-pressure mercury intrusion can derive rocks. ratio thickness near linearly with logarithm size. proposed mathematical gas-water verified comparing normalized curve measured offers alternative estimating when unavailable core samples.