Decomposition of fluiddynamics balance equations
Abstract
The paper formulates the complete set of fluiddynamics balance equations, for Newtonian fluids, in terms of the projections normal and tangential to a surface. This surface can be either a coordinate surface of an arbitrary curvilinear orthogonal coordinate system or a fixed, sufficiently smooth and regular arbitrary surface. The formulation presented in this paper finds its application in all those cases in which one of the three independent directionfields in a threedimensional space needs to be differentiated, for one reason or another, from the other two. Such cases arise in the study of discontinuity surfaces (e.g. higher order boundary layer theories) or surfacetension driven phenomena, and in the analysis of parabolic or quasiparabolic approximations to the NavierStokes equations.
 Publication:

L'Aerotecnica Missili e Spazio
 Pub Date:
 December 1977
 Bibcode:
 1977AerMS..56..183N
 Keywords:

 Flow Equations;
 Fluid Dynamics;
 Newtonian Fluids;
 Three Dimensional Flow;
 Boundary Layer Equations;
 Coordinates;
 Differential Equations;
 Discontinuity;
 Interfacial Tension;
 NavierStokes Equation;
 Projective Geometry;
 Space Commercialization;
 Surface Geometry;
 Fluid Mechanics and Heat Transfer