the partial differential equations for water flow and solute transport in a two-dimensional saturated domain are rendered discrete using the finite difference technique; the resulting system of algebraic equations is solved using a dynamic programming (dp) method. the advantage of the dp algorithm is that the problem is converted from solving an algebraic system of order nc(nl-1) nc(nl-1) into...

in this paper, the approximate solution of the differential system modeling hiv infection of cd4+ t cells isobtained by a reliable algorithm based on an adaptation of the standard variational iteration method (vim), which is called the multi-stage variational iteration method(msvim). a comparison between msvim and the fourthorder runge-kutta method (rk4-method) reveal that the proposed techniqu...

one of the most concerning issues for researchers is to predict the shape and dimensions of the scour pit nearhydraulic structures such as the base of bridges, weirs, valves and stilling basins due to both financial and humanhazards induced by destruction of the structure. as the scour issue has its own complexity in relation to themultiplicity of effecting factors on it, in this study therefor...

in this paper, the effect of electric field on two-dimensional low reynolds air flow around an airfoil and variation of the forces acting on the airfoil is numerically investigated. the electric current and poisson’s equations are solved and the outcome is considered as a source term in the momentum equations. the energy equation is not considered due to its weak effect on the phenomena. the fi...

a fundamental topic in computational fluid dynamics is the role of coordinate particularly for searching optimized coordinates. the objective of this study is the numerical modeling of supersonic flows using a new coordinate system i.e. unified coordinate system (ucs) uses moving mesh with motionless viewing window technique. ucs has an advantage over traditional coordinate systems (eulerian an...

in this paper, we introduce a family of fractional-order chebyshev functions based on the classical chebyshev polynomials. we calculate and derive the operational matrix of derivative of fractional order $gamma$ in the caputo sense using the fractional-order chebyshev functions. this matrix yields to low computational cost of numerical solution of fractional order differential equations to the ...