General Universal Flow Conservation Equation Derived from Global Angular Momentum Conservation and Its Unified Mechanism

The traditional Bernoulli equation is restricted by idealized assumptions such as inviscid, steady, incompressible, and no external work input. It can only describe a very small range of steady flows and cannot explain most real fluid working conditions such as viscous dissipation, transient flow, compressible high-speed flow, and external work. To break through the phenomenological limitations of classical fluid mechanics, this paper takes the global angular momentum zero-conservation axiom as the only first principle, and decomposes fluid motion into a two-component dynamic transformation model of **spin aggregation angular momentum** and **orbital directional angular momentum**. This paper introduces **vacuum medium topological stress tensor trace mapping** to solve the cross-scale physical gap between microscopic vector angular momentum and macroscopic scalar pressure, and adopts **angular velocity power projection and Legendre transformation** to supplement the strict mathematical transition from vector angular momentum balance to scalar energy conservation. Finally, a **general universal flow conservation equation** without any idealized assumptions is constructed. This equation can be continuously degraded into the classical Bernoulli equation, engineering viscous correction equation, unsteady flow equation and compressible flow equation, realizing the global unified mathematical description of laminar flow, turbulent flow, liquid flow, gas flow, transient impact flow and power machinery flow field. This study proves that all fluid pressure-velocity coupling laws are essentially macroscopic emergent effects of medium angular momentum rebalancing, establishing a new first-principle unified paradigm for continuum mechanics.