Plenary Lecture
Deep Insight into the still Hidden Theory of Isoenergetic Flow (Part Two)
Dr. Richard Selescu
Trisonic Wind Tunnel Laboratory
Experimental Aerodynamics Compartment, Flow Physics Department
“Elie Carafoli” National Institute for Aerospace Research
(under the Aegis of the Romanian Academy) - INCAS
ROMANIA
E-mail: rselescu@aero.incas.ro
Abstract: This work studies and clarifies some local physical phenomena in fluid mechanics, in the form of an intrinsic analytic study, regarding the motion, continuity, flow rate and velocity potential equations (for inviscid compressible fluids), and the vortex equation (for viscous incompressible fluids), and finds new first integrals. It continues a series of works presented at some conferences and at a congress during 2008 – 2010, representing a real deep insight into the still hidden theory of isoenergetic flow (a real “physiology of the fluid medium”). Several new functions, surfaces and vectors were introduced: the polytropic integral surfaces, for the motion equation; Selescu’s incompressible roto-viscous vector, for the vortex equation; the 2-D “quasi-stream” function on the 3-D (V, Ω) surfaces, for the continuity equation; the surfaces of iso-normal mass flux density (over which the continuity equation of the steady flow of a compressible fluid in a thick stream tube admits a first integral – the same as for this flow in a thin tube, and whose envelope sheets are just the sections of uniform flow, if they exist), for the flow rate equation; the 3-D stream function vector, allowing new local and global forms for the continuity equation; Selescu’s “quasi-incompressible quasi-potential” (Laplace) lines of a “quasi-uniform” rotational flow of an inviscid compressible fluid, for the velocity (quasi-)potential equation (Steichen). A case of first integrability for the system of equations (motion and continuity) for the steady flow of an inviscid compressible fluid was also considered.
Brief Biography of the Speaker: Senior researcher Richard Selescu graduated as an engineer from the Polytechnic Institute of Bucharest, the Faculty of Mechanics, Department of Aircraft Engineering in 1970. He is working at the National Institute for Aerospace Research “Elie Carafoli’’ – INCAS, Department of Aerodynamics, at the Trisonic Wind Tunnel Laboratory. He received his PhD degree in Aerodynamics and Fluid Mechanics at the Aerospace Engineering Faculty of the “Politehnica” University of Bucharest in 1999. Among the research fields of interest, he approached the analytic modeling in aerodynamics, fluid mechanics and magnetofluid dynamics. Thus, he introduced the following nomenclature: the isentropic surfaces and a 2-D velocity quasi-potential function on these surfaces (in fluid mechanics); the zero-work surfaces for the non-conservative terms in the motion equation (in viscous fluid mechanics and magnetofluid dynamics); some new physical quantities – the roto-viscous vector (in Newtonian viscous fluid mechanics), the incompressible roto-viscous vector (in viscous incompressible fluid mechanics, for the vortex equation), the magneto-hydrodynamic vector (in inviscid magnetofluid dynamics), the roto-visco-magnetic vector (in viscous magnetofluid dynamics) and the magnetic vector (in visco-magnetic magnetofluid dynamics, for the equation of magnetic induction); a new shock-free axisymmetric supersonic flow – the tronconical flow (in supersonic aerogasdynamics); the similarity depth for satisfying the gas-hydrodynamic analogy (in supercritical hydrodynamics). The newest introduced nomenclature is not mentioned.