a +(.V at In the like manner Any property DΦad (.V)d Dt at =+(.V) Substantial(Material derivative Dt at 随体(物质、全)导数4 V V t V a     + ( )   = +     =  (V ) Dt t D  In the like manner Any property Φ , ... T ( ) D V Dt t  = +   Substantial (Material) derivative 随体（物质、全）导数