What is a divergent symbol?

Its operation formula is:

Let a quantity field be given by a (x, y, z) = p (x, y, z) i+q (x, y, z) j+r (x, y, z) k, where p, q and r have first-order continuous partial derivatives, σ is a directed surface in the field and n is a point (x, y).

And Δ p/Δ x+Δ q/Δ y+Δ r/Δ z is called the divergence of vector field A, which means div A =Δp/Δ x+Δ q/Δ y+Δ r/Δ z, where Δ in the above formula is the sign of partial derivative.

Divergence is a vector operator in vector analysis, which corresponds a vector field in a vector space to a scalar field. Divergence describes whether a point in a vector field is a convergence point or an origin point, and figuratively speaking, it means whether most of the vectors in the tiny voxels containing this point are "outward" or "inward".

Extended data:

Application:

1, electromagnetism, electrodynamics

The divergence and rotation of electrostatic field E are not zero, and it is an active irrotational field. Static magnetic field B is a rotating passive field with zero divergence and non-zero curl.

2. In meteorology

Divergence can represent the rate of change of unit volume when a fluid moves. To put it simply, the area where fluid concentrates in motion is convergence, and the area where fluid diverges in motion is divergence. A negative divergence value is convergence, which is beneficial to the development and enhancement of convective weather systems such as cyclones, while a positive divergence value means divergence, which is beneficial to the development of weather systems such as anticyclones.

Usually the most widely used V in meteorology is wind speed? "Horizontal divergence". The expression of horizontal divergence is: div v = Δ u/Δ x+Δ v/Δ y, where u is the wind speed in the X axis direction and v is the wind speed in the Y axis direction. Generally speaking, the X axis represents the tangential direction of the weft (positive from west to east) and the Y axis represents the tangential direction of the warp (positive from south to north).

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