Numerical Computations of a Two-Layer Model for Estuaries

The research described in this paper is aimed at improving the predictive capability of numerical models for estuarine circulation. An improved two-layer model has been developed, which is applicable to the entire estuary including areas near the river mouth and the estuary inlet. This model is applied to Apalachicola Bay, Florida. The calibration and verification of the numerical model is accomplished with available prototype data. The horizontal density gradient terms have been added to the model and provide significantly improved salinity predictions near the river mouths. A theoretical approach to the internal wave boundary condition has been developed in this two-layer model

Numerical Computations for Estuarine Flood Plains

Construction on estuarine flood plains can contribute significantly to flooding problems during times of large river inflow. A two dimensional depth averaged finite difference model is presented which allows for improved environmental impact assessment of construction on estuarine flood plains. The model is applied to the delta region above Mobile Bay, Alabama where a railroad crosses the flood plains. The railroad is built on a fill with trestles at established channels. The model is used to evaluate the effect which the railroad has on known flooding problems in the delta region. Partial calibration and verification of the numerical model is accomplished with available prototype data from previous flood events. The numerical model demonstrates that while a great amount of water may be stored on flood plains, conditions are not generally conducive for large flow rates. Most of the flood still moves along major established channels. Construction on flood plains may exert a significant influence on flood stage elevations in certain regions with other regions experiencing a very minor effect. In particular, construction in the interior of the flood plains may produce large effects in the interior with only minor effects propagating to the boundaries

Lake Erie International Jetport Model Feasibility Investigation. Report 17-9, Results of Numerical Three-Dimensional, Wind-Driven Circulation Analysis for Thermally Stratified Lake Conditions

Source: https://erdc-library.erdc.dren.mil/jspui/The wind-driven circulation for thermally stratified lake conditions in a 16-mile by 16-mile nearshore region offshore Cleveland, Ohio, is studied for existing conditions and conditions as modified by a proposed jetport island. A steady-state 12 mph west wind, which produced maximum jetport effects in a previous WES study of the steady-state wind-driven circulation for well-mixed lake conditions in the nearshore region offshore Cleveland, Ohio, was chosen as the wind field for the model study. In a previous contracted study by WES, a 12 mph south wind, which represents the modal wind speed and most frequently occurring wind direction for the months of July, August, and September, was used in studying the proposed jetport effects on wind-driven circulation for summer lake conditions. For the 12 mph west wind field, results for the horizontal velocity and temperature regimes with and without a jetport are presented. Included in the results are plots of horizontal velocity vectors and isotherm contours with and without a jetport and contours of differences in hori zontal velocity and temperature regimes in the nearshore region due to jetport. Based on the results of this study and a previous WES contracted studyl using a 12 mph south windfield, the effects of a proposed jetport island on wind-driven circulation for thermally stratified lake conditions are that (A.) major island influences of engineering interest are contained within 3 to 5 miles of the island, (B.) velocity changes of 0.25 ft/sec extend to the shore in the immediate vicinity of Cleveland, Ohio, while temperature changes of 0.5°F extend within 1 mile of the shoreline, and (C.) maximum changes in velocity and temperature (1.5 fps and 15°F) regimes occur within 2 miles of the island in strong upwelling and downwelling regions along the perimeter of the island

Numerical Analysis of Tidal Circulation for Long Beach Outer Harbor Proposed Landfill

Source: https://erdc-library.erdc.dren.mil/jspui/A study was conducted for Long Beach Harbor to numerically investigate tidal circulation in existing basins and to define and evaluate the impact of a proposed oil terminal adjacent to pier J on existing harbor circulation. A two-dimensional depth-averaged formulation of the hydrodynamic equations was used in the model and an implicit-explicit finite difference scheme was used to numerically solve the equations. The numerical model had been verified in a previous study using tide and velocity data from the prototype and from physical model tests conducted at WES. Two landfill configurations for the oil terminal along with a channel dredging project in the Port of Los Angeles were considered in the study. Tidal currents were relatively unaffected by the proposed plans except near the oil terminal and the dredging project. Net discharges through the harbor entrances and through Cerritos Channel in the inner harbor were not changed significantly

Lake Erie International Jetport Model Feasibility Investigation. Report 17-4: Numerical Model Feasibility Study

Source: https://erdc-library.erdc.dren.mil/jspui/An integral part of the feasibility assessment of a proposed offshore jetport site near Cleveland, Ohio, is the investigation of the hydrodynamics of Lake Erie to aid in determining the effects of the structure on such phenomena as seiching, storm surge, and lake circulation. To assist in determining these effects, the feasibility of using numerical modeling techniques was investigated. Numerical models that appeared capable of predicting the extent and magnitude of hydrodynamic changes produced by the proposed jetport were reviewed. Based upon this investigation, a determination was made of the feasibility of applying numerical models to the problems of seiching, storm surge, and lake circulation in Lake Erie. The numerical model feasibility study was restricted to the consideration of existing state-of-the-art models. No extensive model development was undertaken in this feasibility study; however, areas where additional numerical development is required were identified. The theoretical limitations, verification, resolution capabilities, and accuracy of the model as well as the cost of application of the model were considered

Lake Erie International Jetport Model Feasibility Investigation. Report 17-10: Nontechnical Summary of Project

Source: https://erdc-library.erdc.dren.mil/jspui/A nontechnical summary of the Waterways Experiment Station's (WES) efforts in a model feasibility investigation of a proposed jetport located in Lake Erie offshore Cleveland, Ohio, is presented in this report. This report is intended to present the basic concepts, procedures and results of the WES model feasibility study without technical details. The following items are some of those presented in a format suitable for the nonscientist : (A.) scope and objectives of WES study; (B.) factors involved in hydrodynamic modeling; (C.) lake characteristics and other information required as input for the models; (D.) methods for obtaining unavailable data; (E.) numerical and physical model evaluation, selection and preliminary design procedures; (F.) information obtained from the models; and (G.) current status of WES modeling efforts. Detailed technical data and results from WES study were published by WES in a series of 12 reports. These reports are referenced throughout this report in the appropriate and related sections