Results 261 to 270 of about 5,991,687 (297)

Approximate analytical solution of nucleation problems

Materials Science and Engineering: A, 1993
Abstract A Fokker-Planck-like equation describing the homogeneous nucleation process in one-component system is solved analytically by a novel method based on boundary layer theory combined with a Green function technique. Important characteristics of nucleation (nucleation rate, integrated flux, time lag) are determined. The accuracy of the approach
P Demo, Z Kožíšek
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An Approximate Analytical Solution to the Sir Model

2021
An analytical expression, a formula, for the removed individuals in an epidemic, as a function of time, is suggested as an approximation of a Susceptible, Infected, Removed (SIR) epiemics dynamics model solution. The formula is shown to have an excellent fitting to real world data, as exemplified by the case of Italy in the New Coronavirus pandemic.
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Approximate analytic solutions for nonsimilar boundary layers.

AIAA Journal, 1967
The Crocco equation for zero pressure gradient and a constant viscosity density product is linearized and the results applied to boundary-layer problems where the given initial profile is much different from the Blasius profile. Four linearization assumptions are used, each of which leads to an eigenvalue problem having a discrete spectrum of ...
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Analytical approximations to the solution of the Blasius equation

Acta Mechanica, 1981
Direct integration of the classical Blasius equation yields a weighted integral condition for the flow. The accuracy of the solution is improved dramatically when the series is rewritten to avoid the region of divergence. The first term of this new series approximates the stress accurately to 0(10{-4}).
Parlange, J. Y., Braddock, R. D., Sander, G.   +2 more
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An approximate analytic solution of the Blasius problem

Communications in Nonlinear Science and Numerical Simulation, 2009
zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Ahmad, Faiz, Al-Barakati, Wafaa H.
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Approximate analytic solution of a quasipotential equation

Theoretical and Mathematical Physics, 1988
A method is proposed for constructing a solution of a relativistic Logunov-Tavkhelidze quasipotential equation in the form of an expansion with respect to eigenfunctions of the nonrelativistic problem. The method is designed for the use of a computer in a system of analytic calculations.
V. I. Savrin, E. M. Shablygin
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Approximate analytic solutions to the Skyrme equation

Journal of Mathematical Physics, 1992
The asymptotic properties and the stability of the solutions of the Skyrme nonlinear differential equation for the profile function F are discussed. Using rational approximants for σ=cos F some different ways of finding approximate analytic solutions to the equation are discussed.
Linde, Johan, Snellman, Håkan
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Approximate Analytical Solutions for the Colebrook Equation

Journal of Hydraulic Engineering, 2018
AbstractFriction factor determination is important for modeling fluid flows in pipes. The Colebrook equation has been widely used for estimating the pipe friction factor in fully developed turbulen...
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Approximate Analytical Solutions for Overland Flows

Water Resources Research, 1990
Following the study of Govindaraju et al. (1988), approximate analytical solutions are presented to the diffusion and kinematic wave models subject to space and time‐varying rainfall. An approximation in the form of the first term of an infinite sine series has been considered. This converts the partial differential equation to an ordinary differential
R. S. Govindaraju, M. L. Kavvas, S. E. Jones   +2 more
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Approximate analytical solutions of the Forchheimer equation

Journal of Hydrology, 2005
In this paper we derive approximate analytical solutions for non-steady-state, non-linear flows through porous media, described by the Forchheimer equation. We demonstrate that one has to distinguish between two characteristic regimes. In early times, the hydraulic gradient is steep, and subsequently the inertial terms are dominant.
Konstadinos N. Moutsopoulos, Vassilios A. Tsihrintzis   +1 more
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