Parametric numerical study of wind barrier shelter

This paper presents an experimental study on strategies of utilizing wind as an architectural element, proposing the reconfiguration and projection of wind patterns to produce vaults of wind as regions of shelter in the outdoor environment. It shows an aerodynamic analysis and exploration of barriers, deflectors and porous screens in an existing urban wind canyon for a hypothetical urban shelter in a tram stop area. Computational Fluid Dynamics (CFD) software and physical tests in a wind tunnel using microelectronic hot-wire anemometry are the methods utilised. The experiments involve a comparison between screens with impermeable surfaces and porous membranes and their ability to project wind as architecture. The experiments showed that the use of porous membranes improves the mitigation level of wind speed and turbulence intensity in the wind vaults regions.

A preprocessing tool for generating input data for aerodynamic design, computational Fluid Dynamics (CFD) analysis and experimental model production is illustrated in a number of design case studies. A set of basic functions as well as gasdynamic flow elements are providing a rich variety of mathematically explicit relations to generate 2D curves, 3D surfaces which may move with time or optimization cycles.

A mesh optimization strategy for accurately estimating the drag of a ground vehicle is proposed based on examining the effect of different mesh parameters. The optimized mesh parameters were selected using a Design of Experiments (DoE) method enabling simulations to be carried out in a limited memory environment, and in a timely manner; without compromising the accuracy of results. The study was extended to take into account the effect of model size. A simplified car model at three scales has been investigated and compared with results from the MIRA model wind tunnel. Parameters that lead to drag values closer to experiment with less memory and computational time have been identified. Scaling the optimized mesh size with the length of car model was successfully used to predict the drag of the other car sizes with reasonable accuracy. This investigation was carried out using STAR-CCM+, a commercial CFD package; however the findings can be applied to any similar CFD code.

Computational Methods in Applied Sciences, 2018

The design of sailing boats appendages requires taking in consideration a large amount of design variables and diverse sailing conditions. The operative conditions of dagger boards depend on the equilibrium of the forces and moments acting on the system. This equilibrium has to be considered when designing modern fast foiling catamarans, where the appendages accomplish both the tasks of lifting up the boat and to make possible the upwind sailing by balancing the sail side force. In this scenario, the foil performing in all conditions has to be defined as a trade-off among contrasting needs. The multi-objective optimization, combined with experienced aerodynamic design, is the most efficient strategy to face these design challenges. The development of an optimization environment has been considered in this work to design the foils for an A-Class catamaran. This study, in particular, focuses on the geometric parameterization strategy combined with a mesh morphing method based on Radial Basis Functions, and managed through the workflow integration within the optimization environment.

16th AIAA Computational Fluid Dynamics Conference, 2003

This paper presents two major additions to our high-fidelity aero-structural design environment. Our framework uses high-fidelity descriptions for both the flow around the aircraft (Euler and Navier-Stokes) and for the structural displacements and stresses (a full finite-element model) and relies on a coupled-adjoint sensitivity analysis procedure to enable the simultaneous design of the shape of the aircraft and its underlying structure to satisfy the measure of performance of interest. The first of these additions is a direct interface to a parametric CAD model that we call AEROSURF and that is based on the CAPRI Application Programming Interface (API). This CAD interface is meant to facilitate designs involving complex geometries where multiple surface intersections change as the design proceeds and are complicated to compute. In addition, the surface geometry information provided by this CAD-based parametric solid model is used as the common geometry description from which both the aerodynamic model and the structural representation are derived. The second portion of this work involves the use of the Finite Element Analysis Program (FEAP) for the structural analyses and optimizations. FEAP is a full-purpose finite element solver for structural models which has been adapted to work within our aero-structural framework. In addition, it is meant to represent the state-of-the-art in finite element modeling and it is used in this work to provide realistic aero-structural optimization costs for structural models of sizes typical in aircraft design applications. The capabilities of these two major additions are presented and discussed. The parametric CAD-based geometry engine, AEROSURF, is used in aerodynamic shape optimization and its performance is compared with our standard, in-house, geometry model. The FEAP structural model is used in optimizations using our previous version of AEROSURF (developed in-house) and is shown to provide realistic results with detailed structural models.

AIAA Defense and Civil Space Programs Conference and Exhibit, 1998

This paper presents a method of transforming aerodynamic datasets generated in Aerodynamic Preliminary Analysis System (APAS) into parametric equations which may subsequently be used in a multidisciplinary design optimization (MDO) environment for analyzing aerospace vehicles.

Computational studies of wind turbines have been growing considerably in recent years. This is due to the fact that the reduction of analysis time, costs in the development of wind turbines and the high reliability of the results. Then, a survey of mesh convergence was conducted, consisting of a mesh with a static external domain and a rotating internal domain for the simulation of a 5 m diameter wind turbine. The turbine studied is a model with three blades, designed with the help of software SDPA 1.0 -Development System for Wind Turbine Blades -developed in the Laboratory of Aerodynamics and Fluid Mechanics. The SDPA computes chord and the twist angle for optimum blade sections according to the theory of BEM. The blade is optimized for a specific speed value λ = 7. with NACA 63215 profile. The meshes were generated by software ANSYS ICEM CFD to different values of downstream distance, upstream distance, static domain diameter, maximal size of elements over the blades, minimal size of elements over the blades, maximal size of external domain and maximal size of internal domain.

2009

It is presented a study for the definition of a windbreak, necessary to create a sheltering effect on a sport complex. The study is directed towards a large sport complex, consisting in a long rowing channel, under development, designed for high-levels of competition. Both experimental and computational (CFD) techniques are used. The erosion technique was used in some of the wind tunnel tests, complemented by wind-speed measurements using a wind-direction sensitive probe. The numerical results are confronted against the experimental data, and the agreement between the two sets is quite satisfactory. Different shelter barriers are computationally modeled, with various geometric and porosity configurations, to define the optimal solution.

R. van Lanen e.a. (red.), De logica van het landschap. Opstellen over archeologie, ecologie en geschiedenis, 2024

Bijdrage aan Liber Amicorum voor B.J. Groenewoudt