However, significantly fewer degrees of freedom are typically needed with BEM in order to get the same accuracy as with FEM. Note that BEM is computationally more demanding than FEM for the same number of degrees of freedom.

Modeling the interaction of radiating and scattering objects located far away from each other where the space in between would otherwise need an FEM-based volumetric mesh.

Models that include an infinite wall or an infinite sound soft boundary located far away from the radiating objects (measured in terms of wavelengths).

As a replacement of an FEM-based radiation condition or an FEM-based perfectly matched layer (PML).

Large fluid domains that would otherwise need an FEM-based volumetric mesh.

Typical cases where using the new BEM-based interfaces is advantageous: This significantly reduces the need for creating large volumetric meshes, making the BEM-based interfaces especially useful for modeling radiation and scattering problems with complex CAD geometries. When using BEM, only the surfaces adjacent to the modeling domain of interest need to be meshed. For example, the interior of a vibrating structure can be modeled with FEM, which allows for more general material properties, whereas the exterior domain is modeled with BEM, which is better suited for modeling large or infinite domains. With this hybrid approach, you can use the best suited method, FEM or BEM, where needed. This includes coupling to vibrating structures, via the Acoustic-Structure Boundary multiphysics coupling, and coupling to FEM acoustic domains, via the new Acoustic BEM-FEM Boundary multiphysics coupling. The image to the left shows the sound pressure level, while the image to the right shows the deformation of the array (there is constant phase shift applied for each row).ДЄdditionally, with COMSOLВ Multiphysics В® 5.3a, you can seamlessly couple the boundary elements interface with the physics interfaces that are based on the finite element method (FEM). In this model, a 'sound-hard' sphere is placed roughly 30 wavelengths away from the source. The results indicate that the collector can operate with optical efficiency of 60%, maximum temperature of 350вЂЇвЊ, thermal efficiency of 51% and 42% at 100вЂЇвЊ and 200вЂЇвЊ respectively while the cost of energy is as low as 2.9 cents/kWh.Interaction between the tonpilz sonar array and a scattering object.

The mathematical, numerical and experimental results were found to have good agreement. Finally, the collector is experimentally tested in three stages to measure maximum temperature, maximum efficiency and thermal efficiency at various temperature of heat transfer fluid. Also, in order to predict the thermal performance of the proposed collector, analytical and numerical simulation are studied. The reflector is truncated using the nonimaging optics methods in order to maximize the optical efficiency while minimizing the material consumption. In this project, Levelized Cost of Heat is optimized with material cost reduction while maintaining high thermal performance using economical aluminum fin (instead of copper), a glass cover and highly truncated aluminum reflector. The focus is the optimization of cost and performance in respect to commercially available medium temperature collectors (100вЂ“300вЂЇвЊ) using thermal and economic index of heat generation system also known as Levelized Cost of Heat. In this manuscript, performance of a novel concentrated solar thermal collector with evacuated tube is studied.

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