US Geological Survey


Date of this Version



Published in Hydraulic Engineering: Saving a Threatened Resource—In Search of Solutions: Proceedings of the Hydraulic Engineering sessions at Water Forum ’92. Baltimore, Maryland, August 2–6, 1992. Published by American Society of Civil Engineers.


A mesh-generating computer program, GNMESH, has been developed to generate two-dimensional finite element meshes for the U.S. Federal Highway Administration's FESWMS-2DH, a two-dimensional depth averaged finite element flow model. GNMESH uses a modified mapping technique that incorporates piecewise Hermitian and weighted interpolation schemes to layout the generated mesh within given or calculated flow tubes. Minimum required input data for GNMESH is required when the program is run using its default settings. These input data consists of the X, Y, and Z coordinates of points defining a minimum of three cross sections, the roughness coefficients at the given cross sections, an estimate of the water surface elevation at each of the cross sections, and the stream discharge. Output of the GNMESH program consists in part of two data files that are formatted in the manner required by the DIN MOD and FLOMOD modules of FESWMS-2DH.