... reservoir fluid phases, possibly oil, gas, and water, might move through the same pores. One phase might move upward while the others move countercurrently downward, or vice versa, in the same pores. If such a mechanism were valid, Darcy s Law could be applied over large areas of the reservoir to provide...

... carrier fluid to flow downwards, stir up the sand particles via a jetting nozzle at the bottom of a sand cleanout pipe, bring the loose sand particles upwards and then to be boosted by using a jet pump. The other part of the fluid acts as the power fluid of the jet pump to reduce the bottomhole pressure...