A Parallel h-Adaptive Finite Element Model for Wind Energy Assessment in Nevada

Author(s):  
Darrell W. Pepper ◽  
Yitung Chen ◽  
Joseph M. Lombardo

A Petrov-Galerkin finite element model that employs local mesh adaptation is being developed to determine potential wind energy sites within the state of Nevada. Meteorological data collected from various private, county, city, and government agencies are used to generate diagnostic flow fields, which subsequently provide initial conditions for the prognostic solution of the time-dependent equations of motion and species transport. The model runs on a multiprocessor SGI Onyx 3800. Results of the data collection, including wind energy site forecasts, will be made available on the web when the assessment for the entire state is completed.

2020 ◽  
Vol 10 (15) ◽  
pp. 5102
Author(s):  
Carlos Valencia Murillo ◽  
Miguel Gutierrez Rivera ◽  
Junuthula N. Reddy

In this paper, a seven-parameter spectral/hp finite element model to obtain natural frequencies in shell type structures is presented. This model accounts for constant and variable thickness of shell structures. The finite element model is based on a Higher-order Shear Deformation Theory, and the equations of motion are obtained by means of Hamilton’s principle. Analysis is performed for isotropic linear elastic shells. A validation of the formulation is made by comparing the present results with those reported in the literature and with simulations in the commercial code ANSYS. Finally, results for shell like structures with variable thickness are presented, and their behavior for different ratios r/h and L/r is studied.


1997 ◽  
Vol 05 (04) ◽  
pp. 383-402
Author(s):  
Tony W. H. Sheu ◽  
C. C. Fang

A hyperbolic equation is considered for the propagation of pressure disturbance waves in layered fluids having different fluid properties. For acoustic problems of this sort, the characteristic finite element model alone does not suffice to ensure prediction of the monotonic wave profile across fluids having different properties. A flux corrected transport solution algorithm is intended for incorporation into the underlying Taylor–Galerkin finite element framework. The advantage of this finite element approach, in addition to permitting oscillation-free solutions, is that it avoids the necessity of dealing with medium discontinuity. As an analysis tool, the proposed monotonic finite element model has been intensively verified through problems which are amenable to analytic solutions. In modeling wave propagation in layered fluids, we have investigated the influence of the degree of medium change on the finite element solutions. Also, different finite element solutions are considered to show the superiority of using the flux corrected transport Taylor–Galerkin finite element model.


Author(s):  
Xiuling Wang ◽  
Darrell W. Pepper ◽  
Yitung Chen ◽  
Hsuan-Tsung Hsieh

Calculating wind velocities accurately and efficiently is the key to successfully assessing wind fields over irregular terrain. In the finite element method, decreasing individual element size (increasing the mesh density) and increasing shape function interpolation order are known to improve accuracy. However, computational speed is typically impaired, along with tremendous increases in computational storage. This problem becomes acutely obvious when dealing with atmospheric flows. An h-adaptation scheme, which allows one to start with a coarse mesh that ultimately refines in high gradients regions, can obtain high accuracy at reduced computational time and storage. H-adaptation schemes have been shown to be very effective in compressible flows for capturing shocks [1], but have found limited use in atmospheric wind field simulations [2]. In this paper, an h-adaptive finite element model has been developed that refines and unrefines element regions based upon velocity gradients. An objective analysis technique is applied to generate a mass consistent 3-D flow field utilizing sparse meteorological data. Results obtained from the PSU/NCAR MM5 atmospheric model are used to establish the initial velocity field in lieu of available meteorological tower data. Wind field estimations for the northwest area of Nevada are currently being examined as potential locations for wind turbines.


2010 ◽  
Vol 60 (4) ◽  
pp. 835-850 ◽  
Author(s):  
David R. Munday ◽  
David P. Marshall ◽  
Matthew D. Piggott

Sign in / Sign up

Export Citation Format

Share Document