AITCH
Flow in an H-Shaped Region

AITCH, a FORTRAN90 program which solves for flow in an H-shaped region.

More specifically, AITCH is intended to model the geometry needed for a time-dependent flow of an incompressible fluid in a 2D region, under the Navier Stokes equations.

This program is simply an initial sketch of how to divide up the the region in a way that makes it possible to generate a consistent account of the nodes and elements needed to implement a finite element representation of the solution.

Licensing:

The computer code and data files described and made available on this web page are distributed under the GNU LGPL license.

Languages:

AITCH is available in a FORTRAN90 version.

Related Data and Programs

aitch_test

FLOW3 is a FORTRAN90 program which solving the 2D steady incompressible Navier Stokes equations using the finite element method.

INOUT is a FORTRAN77 program which computes the pressure and velocity for a Navier Stokes flow in a square region with an inlet and an outlet.

TCELL is a FORTRAN77 program which solves the Navier Stokes fluid flow equations in a "T"-shaped region.

Source Code:

• aitch.f90, the source code.

List of Routines:

• AITCH tests the AITCH geometry routines.
• AITCH_DOF_NUM determines the number of degrees of freedom in the region.
• AITCH_ELEMENT_NODE determines the nodes that make up each element.
• AITCH_ELEMENT_NUM determines the number of elements in the region.
• AITCH_NODE_DOF_SET assigns degrees of freedom to each node.
• AITCH_NODE_NUM determines the number of nodes in the region.
• AITCH_NODE_XY assigns coordinates to each node.
• ELEMENT6_EPS creates an EPS file containing an image of the mesh.
• ELEMENT_NODE_BANDWIDTH determines the bandwidth associated with the grid.
• ELEMENT_NODE_PRINT prints the elements.
• GET_UNIT returns a free FORTRAN unit number.
• NODE_DOF_INDEX_PRINT prints the nodal degrees of freedom.
• NODE_EPS creates an EPS file containing an image of the nodes.
• NODE_XY_PRINT prints the node coordinates.
• TIMESTAMP prints the current YMDHMS date as a time stamp.
• TIMESTRING writes the current YMDHMS date into a string.