Dynamic Simulation of Littoral Zone Habitats in Lower Chesapeake Bay. I. Ecosystem Characterization Related to Model Development

Estuaries ◽  
1998 ◽  
Vol 21 (4) ◽  
pp. 659 ◽  
Author(s):  
Christopher P. Buzzelli
Keyword(s):  
Chesapeake Bay ◽  
Dynamic Simulation ◽  
Littoral Zone ◽  
Model Development

Dynamic Model Development of Linear Fresnel Solar Field

2015 ◽  
Author(s):  
Elina Hakkarainen ◽  
Matti Tähtinen ◽  
Hannu Mikkonen
Keyword(s):  
Control System ◽  
Dynamic Simulation ◽  
Model Development ◽  
Control Mode ◽  
Plant Behavior ◽  
Clear Sky ◽  
Control Scheme ◽  
Control Schemes ◽  
And Control ◽  
Solar Field

As a dispatchable clean energy source, concentrated solar power (CSP) can be one of the key technologies to overcome many problems related to fossil fuel consumption and electricity balancing problems. Solar is a variable location, time and weather dependent source of energy, which sets challenges to solar field operations. With proper dynamic simulation tools it is possible to study dynamics of CSP field under changing weather conditions, find optimum control strategies, and plan and predict the performance of the field. CSP technology considered in this paper, linear Fresnel reflector (LFR), is a proven line focusing technology, having simpler design but suffering in optical performance compared to more mature parabolic trough (PT) technology. Apros dynamic simulation software is used to configure and simulate the solar field. Apros offers a possibility to dynamically simulate field behavior with varying collector configuration, field layout and control mode under varying irradiation conditions. The solar field applies recirculation (RC) as a control mode and direct steam generation (DSG) producing superheated steam. DSG sets challenges for the control scheme, which main objective is to maintain constant steam pressure and temperature at the solar field outlet under varying inlet water and energy conditions, while the steam mass flow can vary. The design and formulation of an entire linear Fresnel solar field in Apros is presented, as well as the obtained control scheme. The field includes user defined amount of collector modules, control system and two modules describing solar irradiation on the field. As two-phase water/steam flow is used, an accurate 6-equation model is used in Apros. Irradiation on the solar field under clear sky conditions is calculated according to time, position and Linke turbidity factor. Overcast conditions can be created by the clear sky index. For LFR single-axis sun tracking system is applied. In order to test the model functionality and to investigate the field behavior, thermal performance of the field was simulated at different dates at two different locations, and the results were compared. Similar field dimensions and control schemes were applied in each case, and simulations were done for full 24 hours in order to study the daily operations and ensure process stability. Control scheme functionality is evaluated based on the plant behavior in simulation cases having different operational conditions. The proper operability of the configured LFR model is evaluated. Obtained performance results show differences between locations and variation depending on season and time. The importance of a proper control system is revealed. The results show that the dynamic model development of a solar field is necessary in order to simulate plant behavior under varying irradiation conditions and to further develop optimal field control schemes and field optimizing process. The future work in the development of the LFR model presented will focus on dynamic response behavior development under transient conditions and field start-up and shut down procedure development.

scholarly journals ISLAND RESTORATION TO MEET 'TRIPLE-WIN' ENGINEERING WITH NATURE OUTCOMES

2020 ◽  
pp. 11
Author(s):  
Paula Whitfield ◽  
Jenny Davis ◽  
Danielle Szimanski ◽  
Jeffrey King ◽  
Joe Gailani ◽  
...  
Keyword(s):  
Ecosystem Services ◽  
Sea Level Rise ◽  
Chesapeake Bay ◽  
Sea Level ◽  
Model Development ◽  
Environmental Benefits ◽  
Dredged Sediment ◽  
Island Restoration ◽  
Shoreline Protection ◽  
Restoration Monitoring

The coastal islands and marshes of Chesapeake Bay USA, are disappearing along with the ecosystem services and infrastructure/shoreline protection they provide. To counter such losses, the USACE Baltimore District is restoring historic island footprints using dredged sediments. Islands constitute an important natural and nature-based feature (NNBF) that meet the 'triple win outcomes' of USACE's Engineering With Nature (EWN) initiative, by providing economic, social and environmental benefits. Here we highlight the restoration and monitoring of Swan Island using 61,000 cubic yards of dredged sediment. The creation/expansion of Swan Island, is expected to produce significant benefits in terms of ecosystem services, increased resilience to future sea level rise, and abatement of erosive losses to an adjacent coastal community. The pre- and post-restoration monitoring and model development by project partners will serve to quantify the benefits and efficacy of the island restoration thereby facilitating island restoration as a viable NNBF option in the future.Recorded Presentation from the vICCE (YouTube Link): https://youtu.be/2kvSVcH2KuE

An Integrated Approach for Numerical Simulation of Full Vehicle Behaviour During Transient Dynamic Maneuvers on Arbitrary Obstacles and Road Surfaces

2003 ◽  
Author(s):  
E. Duni ◽  
G. Monfrino ◽  
R. Saponaro ◽  
M. Caudano ◽  
F. Urbinati ◽  
...  
Keyword(s):  
Finite Element ◽  
Dynamic Simulation ◽  
Model Development ◽  
Integrated Approach ◽  
Element Model ◽  
Experimental Comparison ◽  
Transient Dynamic Analysis ◽  
Transient Dynamic ◽  
Full Vehicle ◽  
Stage Of Development

This work describes a numerical methodology based on the finite element method used for the transient dynamic simulation of the full vehicle rolling on different kind of obstacles. Some issues related to the tire finite element model development and its validation, by numerical-experimental comparison, have been discussed. The strategy to combine the static simulations such as the tire inflating, the vehicle weight application and suspension pre loading, with transient dynamic analysis of the car rolling over the obstacle has been chosen. The methodology, based on integration of Abaqus Implicit and Explicit codes, has been successfully applied for the dynamic simulation of Fiat Punto car passing over comfort and pothole obstacle; it is in a good stage of development for a bump obstacle (misuse airbag test).

Between ‘Savage Man’ and ‘Most Faithful Englishman’ Manteo and the Early Anglo-Indian Exchange, 1584–1590

Itinerario ◽  
2000 ◽  
Vol 24 (2) ◽  
pp. 146-169 ◽  
Author(s):  
Michael Leroy Oberg
Keyword(s):  
North Carolina ◽  
Chesapeake Bay ◽  
One Year ◽  
Anglo Indian

In August of 1587 Manteo, an Indian from Croatoan Island, joined a group of English settlers in an attack on the native village of Dasemunkepeuc, located on the coast of present-day North Carolina. These colonists, amongst whom Manteo lived, had landed on Roanoke Island less than a month before, dumped there by a pilot more interested in hunting Spanish prize ships than in carrying colonists to their intended place of settlement along the Chesapeake Bay. The colonists had hoped to re-establish peaceful relations with area natives, and for that reason they relied upon Manteo to act as an interpreter, broker, and intercultural diplomat. The legacy of Anglo-Indian bitterness remaining from Ralph Lane's military settlement, however, which had hastily abandoned the island one year before, was too great for Manteo to overcome. The settlers found themselves that summer in the midst of hostile Indians.

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