TABLE OF CONTENTS Definition: A Newtonian fluid is a substance that may resist a shearing (tangential) stress no matter how small only by continuous motion.
The application of fundamental fluid mechanics to coastal and ocean engineering problems for an incompressible fluid may be reduced to solving two equations for two unknowns. The fundamental goal of fluid mechanics is to find the two fundamental unknowns if the fluid is incompressible; viz. pressure (a scalar quantity) and velocity (a vector quantity) everywhere in the fluid field. This may be viewed as analogous to the problem of finding the state of stress and strain everywhere in a structural member in solid mechanics. The major difference between these two classes of analogous problems is that the constitutive relationship in solid mechanics that is given by Hooke s Law that relates stress to strain; while in fluid mechanics the analogous constitutive relation is Newton s law of viscosity that relates stress to rate strain (Schlicting, 1979). The definition of a fluid implies a zero yield stress because fluids must flow continuously when subjected to shearing (tangential) forces no matter how small; and, consequently, the mass density, pressure and velocity must be computed for a compressible fluid.
The general problem solution technique (PST) applied in this review is to solve first for the velocity from the conservation of mass equation for an incompressible fluid and to then solve for the pressure from the momentum (or energy) principle, For the irrotational flow of an ideal fluid (i.e. an...
