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J. K. Lee

Publications and source records attributed to J. K. Lee.

8 recordsLinked to original sources
USGS1989

Convergance experiments with a hydrodynamic model of Port Royal Sound, South Carolina

A two-demensional, depth-averaged, finite-difference, flow/transport model, SIM2D, is being used to simulate tidal circulation and transport in the Port Royal Sound, South Carolina, estuarine system. Models of a subregion of the Port Royal Sound system have been derived from an earlier-developed model of the entire system having a grid size of 600 ft. The submodels were implemented with grid sizes of 600, 300, and 150 ft in order to determine the effects of changes in grid size on computed flows in the subregion, which is characterized by narrow channels and extensive tidal flats that flood and dewater with each rise and fall of the tide. Tidal amplitudes changes less than 5 percent as the grid size was decreased. Simulations were performed with the 300-foot submodel for time steps of 60, 30, and 15 s. Study results are discussed.

South Carolina↗
USGS1984

Potential flow through channel constriction.

Potential flow through an eccentric, normal constriction of zero thickness in an infinitely long, straight channel of constant width and unit depth is studied by use of a Schwarz-Christoffel transformation. The transformation is integrated by a direct approach. Parametric equations for streamlines are obtained and used to compute an average streamline length for a potential-flow field. -from ASCE Publications Information

Journal of Hydraulic Engineering↗
USGS1982

A Two-dimensional finite-element model study of backwater and flow distribution at the I-10 crossing of the Pearl River near Slidell, Louisiana

A two-dimensional finite-element surface-water flow modeling system was used to study the effect of Interstate Highway 10 on water-surface elevations and flow distribution during the flood on the Pearl River on April 2, 1980, near Slidell, La. A finite-element network was designed to represent the topography and vegetative cover of the study reach. Hydrographic data collected for the 1980 flood were used to calibrate the flow model. The finite-element network was then modified to represent conditions prior to roadway construction, and the hydraulic impact of I-10 was determined by comparing ' before ' and ' after ' results. Upstream from the roadway, maximum backwater at the west edge of the flood plain (1.5 ft) is greater than maximum backwater at the east edge (1.1 ft). Backwater ranging from 0.6 to 0.2 ft. extends more than a mile downstream from the Pearl River bridge opening in I-10 at the east edge of the flood plain, and drawdown of 0.2 ft. or more occurs along approximately 2 miles of the west edge of the flood plain downstream from I-10. The capability of the modeling system to simulate the significant features of steady-state flow in a complicated multi-channel river-flood-plain system with variable topography and vegetative was successfully demonstrated in this study. (USGS)

Water-Resources Investigations Report↗
USGS1981

A finite-element model study of the impact of the proposed I-326 crossing on flood stages of the Congaree River near Columbia, South Carolina

A two-dimensional finite element surface water model was used to study the hydraulic impact of the proposed Interstate Route 326 crossing of the Congaree River near Columbia, SC. The finite element model was assessed as a potential operational tool for analyzing complex highway crossings and other modifications of river flood plains. Infrared aerial photography was used to define regions of homogeneous roughness in the flood plain. Finite element networks approximating flood plain topography were designed using elements of three roughness types. High water marks established during an 8-yr flood that occurred in October 1976 were used to calibrate the model. The maximum flood of record, an approximately 100-yr flood that occurred in August 1908, was modeled in three cases: dikes on the right bank, dikes on the left bank, and dikes on both banks. In each of the three cases, simulations were performed both without and with the proposed highway embankments in place. Detailed information was obtained about backwater effects upstream from the proposed highway embankments, changes in flow distribution resulting from the embankments, and local velocities in the bridge openings. On the basis of results from the model study, the South Carolina Department of Highways and Public Transportation changed the design of several bridge openings. A simulation incorporating the new design for the case with dikes on the left bank indicated that both velocities in the bridge openings and backwater were reduced. A major problem in applying the model was the difficulty in predicting the network detail necessary to avoid local errors caused by roughness discontinuities and large depth gradients. (Lantz-PTT)

South Carolina↗