عملکرد جدید در نسخه 6.1

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عملکرد جدید در نسخه 6.1

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عملکرد جدید در نسخه 6.1
مولتیفیزیک جریان آکوستیک جدید
دو جریان آکوستیک جدید از آکوستیک فشاری و جریان صوتی از رابط‌های چندفیزیکی Thermoviscous Acoustics برای مدل‌سازی پدیده فیزیکی جریان صوتی استفاده می‌شوند، یعنی زمانی که یک میدان صوتی جریان سیال را القا می‌کند. کوپلینگ‌های چندفیزیکی کوپلینگ دامنه جریان صوتی و جفت مرزی جریان صوتی برای محاسبه نیروها، تنش‌ها و سرعت‌های لغزش مرزی که میدان صوتی در سیال ایجاد می‌کند و جریان ایجاد می‌کند، استفاده می‌شوند. رابط ها یک میدان صوتی حوزه فرکانس را به یک جریان سیال ثابت یا وابسته به زمان پیوند می دهند. جریان صوتی در میکروسیال‌ها و سیستم‌های آزمایشگاهی روی تراشه برای کاربردهایی مانند جابجایی ذرات، اختلاط سیالات و پمپ‌های میکروسیال مهم است.
مش با کنترل فیزیک برای فیزیک آکوستیک
تولید مش کنترل شده با فیزیک به رابط های صوتی بیشتر گسترش یافته است. یک مش کنترل شده توسط فیزیک منجر به تولید یک مش اولیه خوب می شود که بهترین شیوه های مش بندی را انجام می دهد، پدیده های موج را حل می کند و لایه های مرزی را ایجاد می کند. مش با کنترل فیزیک برای موارد زیر اضافه شده است:
آکوستیک فشار، عنصر مرزی
آکوستیک فشار، Kirchhoff-Helmholtz
آکوستیک فشار، پراکندگی مجانبی
آکوستیک فشار، زمان صریح
آکوستیک فشار غیرخطی، زمان صریح
امواج الاستیک، زمان صریح
آکوستیک ترموویسکوز، دامنه فرکانس
آکوستیک ترموویسکوز، گذرا
کوپلینگ چندفیزیکی مرزی ترموویسکوز-ترموالاستیسیته
دو واسط چندفیزیکی جدید، برهمکنش ترموویسکوز آکوستیک-ترموالاستیسیته، دامنه فرکانس و برهم کنش آکوستیک-ترموالاستیسیته ترموویسکوز، رابط گذرا، ترکیبی از آکوستیک ترموویسکوز، دامنه فرکانس یا گذرا با رابط چندالاستیسیته ترموویسکوزیر با استفاده از واسط چندالاستیسیته ترموویسکوز جدید . رابط‌های چندفیزیکی جفت‌های چندفیزیکی از پیش تعریف‌شده بین میدان جابجایی و دما در جامد و تغییرات صوتی در فشار، سرعت و دما در حوزه سیال را حل می‌کنند.
می‌توان از آن برای مدل‌سازی پاسخ ارتعاشی دستگاه‌های MEMS، از جمله توصیف دقیق میرایی، استفاده کرد. رابط های چندفیزیکی در هندسه های متقارن محوری سه بعدی، دو بعدی و دو بعدی موجود هستند.
این عملکرد به هر دو ماژول آکوستیک و ماژول MEMS نیاز دارد
مرز بلندگوی توده‌دار و مرز بلندگوی داخلی برای آکوستیک فشار، گذرا
The Lumped Speaker Boundary and the Interior Lumped Speaker Boundary conditions have been added to the Pressure Acoustics, Transient interface to model hybrid lumped–FEM loudspeaker setups. The condition sets up couplings between the boundary condition and an Electrical Circuit interface. This makes it possible to set up models that can include the large signal parameters like CMS(x), BL(x), or RMS(v) in a simplified way. Predefined global variables exist for the axial position and velocity.
LUMPED SPEAKER BOUNDARY AND INTERIOR LUMPED SPEAKER BOUNDARY FOR THERMOVISCOUS ACOUSTICS, FREQUENCY DOMAIN AND TRANSIENT
The two new boundary conditions, Lumped Speaker Boundary and Interior Lumped Speaker Boundary, have been added to Thermoviscous Acoustics in the frequency domain and in the time domain. This completes and extends the existing conditions available in pressure acoustics. The setup and modeling of microspeakers with hybrid lumped–FEM representations is now simple in thermoviscous acoustics. The lumped representations are also often accurate over a larger frequency range for microtransducers as breakup effects occur outside the intended frequency range. In the time domain, nonlinear effects can be included through large signal parameters like CMS(x), BL(x), or RMS(v).
LUMPED PORT IN THERMOVISCOUS ACOUSTICS
The Lumped Port feature connects a waveguide or duct inlet or outlet to a lumped representation element. This can be an Electrical Circuit (lumped electroacoustic representation), a two-port network defined through a transfer matrix, or a lumped representation of a waveguide. Basically, it couples the end of a waveguide with an exterior system that has a given acoustic lumped representation. Several representations and sources exist for describing the lumped system. When using the lumped port representation, it is assumed that only plane pressure waves — that is, the (0,0)-mode — propagate in the acoustic waveguide. The condition ensures a mathematically and physically consistent coupling, including the thermoviscous boundary layers in the waveguide.
NEW CONVECTED ACOUSTIC-STRUCTURE BOUNDARY, TIME EXPLICIT MULTIPHYSICS COUPLINGS
The new Convected Acoustic-Structure Boundary, Time Explicit and Pair Convected Acoustic-Structure Boundary, Time Explicit multiphysics couplings are used to couple the Convected Wave Equation, Time Explicit interface with the Elastic Waves, Time Explicit interface. The conditions are added on the boundary or pair selection between the fluid domain and the solid domain for modeling acoustic–structure interaction (ASI) or vibroacoustic problems in the presence of a stationary background flow.
NEW FRACTURE BOUNDARY CONDITION IN ELASTIC WAVES, TIME EXPLICIT
The new Fracture condition, available with the Elastic Waves, Time Explicit physics interface, is used to treat two elastic domains with imperfect bonding. The fracture can be, for example, a thin elastic layer, a fluid-filled layer, or it can be a discontinuity in elastic materials (an interior boundary). Several options exist for specifying the properties of the thin elastic domain. Typical applications are for modeling nondestructive testing (NDT) applications, like the response of delamination regions or other defects, or for modeling wave propagation in fractured solid media in the oil and gas industry.
PIEZOELECTRIC WAVES, TIME EXPLICIT NEWS
Improved accuracy and efficiency when solving models involving piezoelectric effects using the time-explicit method. The performance when solving large models on a cluster architecture has also been highly improved to take full advantage of the distributed computing.
PRESSURE ACOUSTICS, TIME EXPLICIT NEWS
The Impedance conditions now use an improved numerical flux formulation for stability, ensuring that both acoustically hard and soft boundaries result in a stable solution.
Two new conditions have also been added to model a transfer impedance setup: the Interior Impedance and the Pair Impedance conditions. Both conditions also take advantage of the improved numerical flux from the impedance condition.
ELASTIC WAVES, TIME EXPLICIT NEWS
In 2D models, the underlying equations have been reformulated to be more efficient for these specific cases. In 2D models, there is now a plane strain option for the out-of-plane component, which you activate by selecting the Include out-of-plane components check box in the 2D Approximation section. The formulation in 2D axisymmetric models has also been improved. As an example, the number of degrees of freedom (DOFs) solved for in the Seismic Waves Earth tutorial model have been reduced from 17·106 to 12·106.
NEW TRANSFER MATRIX COUPLING BOUNDARY CONDITION IN PRESSURE ACOUSTICS, FREQUENCY DOMAIN
The new Transfer Matrix Coupling boundary feature is used to couple two boundaries (source and destination) using a transfer matrix representation. The transfer matrix is a reduced or lumped representation of the physical domain, connecting the two boundaries. The feature has two options, a so-called pointwise coupling and a lumped representation.
EXTENDED THERMAL CONDITIONS IN THE THERMOVISCOUS BOUNDARY LAYER IMPEDANCE CONDITION
A new Thermally Conductive Wall option exists in the Thermoviscous Boundary Layer Impedance condition. The new option makes it possible to model nonideal thermal isothermal or adiabatic wall condition using different analytical representations of walls of finite thickness or infinite walls.
New variables for the evaluation of the combined dissipated and transported energy (including convective terms) in the boundary layers have been added. The variables are useful when modeling heating and not only dissipation.
SPEEDUP OF EVALUATIONS BASED ON THE KIRCHHOFF-HELMHOLTZ KERNEL
Features that rely on the evaluation of the Kirchhoff–Helmholtz integral are now evaluated up to 50% faster compared to the previous version (the value depends on the hardware and the complexity of the plot — more gain is achieved as complexity increases). This is in the Exterior Field Calculation feature that is used in pressure acoustics for plotting the exterior field in results. In the high-frequency acoustics interfaces — Pressure Acoustics, Asymptotic and Pressure Acoustics, Kirchhoff-Helmholtz — this is, in particular, important as the actual computation time lies in the evaluation of the kernel. As an example, the evaluation time of the last plot in the Submarine Asymptotic Scattering tutorial has decreased by 25%.
NEW POROUS LAYER IMPEDANCE OPTIONS FOR PRESSURE ACOUSTICS
The Porous Layer option in the Impedance boundary condition has been updated to include options to handle a certain degree of angle dependency of the impedance. The angle of incidence can be controlled to be normal to the surface or to use a specific angle or direction. An automatic option assigns an effective angle of incidence, which is useful when simulating, for example, room acoustics simulations with diffuse acoustic fields.
RAY ACOUSTICS IMPROVEMENTS
Export of Balloon Data with Method Call
The Application Library model Loudspeaker Driver in a Vented Enclosure now includes a Method and a Method Call that enable the export of the loudspeaker radiation data (balloon plot) in a format suited for further use. This is an example of how custom export can be made using a method and the Application Builder.
Improved Pseudorandom Number Generation
The Ray Acoustics interface includes several features that rely on pseudorandom number generation (PRNG), such as conditional ray–boundary interaction and diffuse or isotropic scattering at boundaries. For such features, the use of pseudorandom number generators have been extensively reviewed and revised. The new expressions are much less likely to incur unwanted correlations between random numbers that should be completely uncorrelated. This includes random boundary conditions acting on different rays, as well as unwanted correlations between different randomly generated vector components.
Option to Only Store Accumulated Variables in Solution
Depending on your application, the accumulated variables (such as sound pressure level on boundaries) might be more valuable information than the position and direction of individual rays. To reduce file size, you now have the option to only retain the accumulated variables in the solution while discarding the degrees of freedom associated with the rays.
Release From Exterior Field
The Release From Exterior Field feature can now pick up exterior fields from Pressure Acoustics, Kirchhoff Helmholtz and Pressure Acoustics, Asymptotic Scattering. Moreover, the feature now handles solving for several frequencies in a parametric sweep.
FLOW-INDUCED NOISE IMPROVEMENTS
The excess pressure terms are now included in the Lighthill stress tensor. These describe the deviations from linear isentropic behavior, for example, if strong nonlinear effects occur in the source region or if a heat source is present in the flow simulation.
The Aeroacoustic Flow Source Coupling multiphysics feature now allows the source to be taken from the new Detached Eddy Simulation (DES) fluid flow interface. The Large Eddy Simulation (LES) fluid flow interface has several new features, including a Synthetic Turbulence option for inlets. See further details in the CFD Module release text.
PREDEFINED PLOT SUGGESTIONS
Several predefined acoustics plots have been to the Add Predefined Plot menu in the Results section. The new predefined plots automatically set up useful plots for several situations:
Plots for multiphysics configurations showing the pressure or sound pressure level, for coupled pressure and thermoviscous acoustic or pressure acoustic and poroelastic waves models.
A plot of the cell-wave time scale, when solving models based on the discontinuous Galerkin time-explicit formulation. This plot is useful for identifying problematic mesh regions that limit the internal time stepping.
SOLVER SUGGESTION IMPROVEMENTS
Several new iterative solver suggestions have been added and improvements have been made to the existing generated solver suggestions. The most important are:
برای مدل‌های آکوستیک فشار، دامنه فرکانس، حل‌کننده تکراری پیشنهادی بر اساس روش لاپلاس جابجا شده برای هم‌گرایی سریع‌تر بهبود یافته است.
برای مدل‌های Thermoviscous Acoustics، پیشنهاد حل‌کننده تکراری مبتنی بر روش تجزیه دامنه برای استفاده از آخرین فناوری حل‌کننده بهبود یافته است. حل کننده اکنون گزینه خوبی برای حل مدل های بزرگتر است.
پیشنهادات حل‌کننده نیز برای حل مدل‌های ارتعاشی سه بعدی مانند بلندگوها و مبدل‌های دیگر اضافه شده است. به طور خاص، یک پیشنهاد حل‌کننده تکراری کارآمد هنگام جفت کردن آکوستیک (آکوستیک فشار و ترموویسکوز)، ساختارها (جامد و/یا پوسته)، و فیزیک میدان‌های مغناطیسی با استفاده از کوپلینگ لورنتس یا کوپلینگ‌های چندفیزیکی نیروهای مغناطیسی مکانیکی ارائه می‌شود.