Method for calculating nitrogen gas filling pressure loss in mined cavity zone based on minimum flow unit

摘要

The present invention discloses a method for calculating a cavity zone nitrogen gas filling pressure loss based on a minimum flow unit, (1) building a minimum flow model of a mined cavity zone (goaf, 采 空), and using the minimum flow unit of the minimum flow model. Confirming; (2) subjecting the minimum flow unit to a study subject, and the flow process is divided into four steps according to a relational expression in which the cross-sectional area changes according to the flow distance, and determining the area expression of the flow cross-section of each step; (3) according to the Navier-Stocks equation, determining a pressure loss value at which nitrogen gas flows in the minimum flow unit. The present invention can quickly calculate the pressure loss during the flow of nitrogen gas, theoretically support the initial pressure required by nitrogen gas when nitrogen gas is injected, and can accurately calculate the injection range, and realize the calculation process. Simple and convenient.