### Keywords : differential equations

##### About Fuzzy Differential Equations

Basil Younis Thanoon; Asmaa Ziyad Al-Katib

AL-Rafidain Journal of Computer Sciences and Mathematics, 2014, Volume 11, Issue 2, Pages 13-25
DOI: 10.33899/csmj.2014.163753

This paper deals with the fuzzy initial value problem and how to solve a linear fuzzy differential equation of first order  when the initial condition is a triangle fuzzy number. This problem is then developed to the case  when the initial condition is a trapezoidal fuzzy number. The paper includes also the issue of the representation of a system of linear fuzzy differential equations, a more general system of  linear fuzzy differential equations is then proposed and the solution of this system is also given. An illustrative examples are given in order to consolidate the raised ideals.

##### Curtain Coating Flow of an Inclined Thin Liquid Films

Faraidun K. Hama Salh

AL-Rafidain Journal of Computer Sciences and Mathematics, 2007, Volume 4, Issue 2, Pages 99-111
DOI: 10.33899/csmj.2007.164019

The mechanism of thin liquid films on solid surfaces is fundamental to a wide variety of phenomena such as surface coatings in paint. A mathematical model is constructed to describe the two dimensions of steady thin liquid films flow on an inclined plane with  the use of lubrication approximation, we have applied Navier-Stokes equations in two dimensional coordinates for  flow of incompressible fluid with the specified boundary conditions, and the solution of the film thickness equation  has been drawn for flow for several inclination angles which modify  the shape  of the emerging patterns and also we derived the third order differential equations that govern such flow.  Finally the equations have been solved analytically.

##### Steady Flow in a Symmetric Thin Liquid Film on an Inclined Surface

Joseph Gh. Abdul-Ahad; Khidr M.S. Khidr

AL-Rafidain Journal of Computer Sciences and Mathematics, 2005, Volume 2, Issue 2, Pages 51-65
DOI: 10.33899/csmj.2005.164088

In this paper, we consider steady incompressible viscous flow in a symmetric thin liquid film on an inclined surface with angle b in two dimensions with no inertia force. The surface of the film is taken to be real that is there is no shear stress on the liquid surface. We found the differential equations that govern the flow. We solve these equations numerically by using Rang Kutta method.