Aerodynamic domain

The coupling method allows to combine different interpolation methods for different model components. For the case of complex structural models with differently resolved components, this is a very important feature for fluid-structure coupling. Therefore, the structural and aerodynamic domain is spitted into several domains. These domains can be components, or further divided components to increase the numerical performance of certain interpolation methods. The technical integration of Nastran into the process is done via file exchange. Either binary or ASCn files are written and read to exchange forces and displacements. The data exchange of all FlowSimulator modules is done in memory. 

In physical terms, particles are classified into different domains relative to their predominant mechanism of mechanical particle transport. Particles smaller than 0.1 pm are related to the thermodynamic domain and particles larger than 1 pm to the aerodynamic domain. A transitional domain is defined for those particles with diameters between 0.1 and 1 pm (10). A detailed overview of the different particle classifications is given in Chapter 1. 

Tracheobronchiolar Deposition Fast-Cleared Thoracic Deposition Aerodynamic Domain... 

A closely related method is that of Boley (B8), who was concerned with aerodynamic ablation of a one-dimensional solid slab. The domain is extended to some fixed boundary, such as X(0), to which an unknown temperature is applied such that the conditions at the moving boundary are satisfied. This leads to two functional equations for the unknown boundary position and the fictitious boundary temperature, and would, therefore, appear to be more complicated for iterative solution than the Kolodner method. Boley considers two problems, the first of which is the ablation of a slab of finite thickness subjected on both faces to mixed boundary conditions (Newton s law of cooling). The one-dimensional heat equation is once again... 

Abstract This chapter reviews atomization modeling works that utilize boundary element methods (BEMs) to compute the transient surface evolution in capillary flows. The BEM, or boundary integral method, represents a class of schemes that incorporate a mesh that is only located on the boundaries of the domain and hence are attractive for free surface problems. Because both primary and secondary atomization phenomena are considered in many free surface problems, BEM is suitable to describe their physical processes and fundamental instabilities. Basic formulations of the BEM are outlined and their application to both low- and highspeed plain jets is presented. Other applications include the aerodynamic breakup of a drop, the pinch-off of an electrified jet, and the breakup of a drop colliding into a wall. 

Hyperbolic equations, like parabolic ones, are also equations of evolution. Although steady flows in aerodynamics, for example, can be both elliptic and hyperbolic (representing, respectively, subsonic and supersonic flow), the latter are not as often found in petroleum reservoir simulation except for certain immiscible two-phase flows dominated by inertia. They describe seismic wave propagation in the earth, but this subject, being entirely different, is not discussed here. These equation classifications are mathematical ones that apply to the equation only. Seismic waves and well test transients excited by periodic disturbances, such as thumpers and oscillating pistons, which are respectively hyperbolic and parabolic in the time domain, satisfy elliptic equations when the governing equations are expressed in the frequeney domain. 

A fully coupled time-domain simulation is the most desirable approach. The reason is that it allows the actual wind loads on the blades to be evaluated correctly, taking into account that the oscillations of the tower top, induced by the earthquake ground motion, affect the rotor aerodynamics (in particular, the relative wind speed at the blades, depending on which lift and drag forces are calculated). However, for the implementation of fully coupled time-domain simulations, dedicated software packages are required, capable of solving the nonlinear motion equations of the structural system under simultaneous wind and seismic excitations. 

Fully coupled time-domain simulations involve only full system models as they require modeling the rotor aerodynamics, with the earthquake ground motion simultaneously acting at the tower base. 

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