NVH
FRF for a rectangular plate
This example shows how to setup the keywords for FRF computation. A nodal force excitation is defined. Frequency dependent response amplitudes at nodes are computed. Differences between constant and mode dependent modal damping can be studied. Example 4.1 from LS-Dyna training class NVH, Fatigue and Frequency Domain Analysis with LS-DYNA by Yun Huang.
FRF for a cantilever with pre-stress condition
This cantilever model shows how to run FRF examples with pre-stress condition. The first file shows the usual *FREQUENCY_DOMAIN_FRF setup without pre-stress. In the second file *INTERFACE_SPRINGBACK_LSDYNA is used to create a dynain-file, which is then the basis for pre-stress analysis with *INCLUDE. In addition, usage of intermittent eigenvalue analysis is shown. Example 4.2 from LS-Dyna training class NVH, Fatigue and Frequency Domain Analysis with LS-DYNA by Yun Huang.
FRF for a column model with a hole (solid elements)
This example shows a column with a hole using solid elements. *FREQUENCY_DOMAIN_FRF is used to define x-acceleration excitation to the base. Response at different output nodes can be studied. Example 4.3 from LS-Dyna training class NVH, Fatigue and Frequency Domain Analysis with LS-DYNA by Yun Huang.
Nodal/Resultant force FRF
This example shows a beam model with two layers of solids. *FREQUENCY_DOMAIN_FRF is used to define z-acceleration to the left end and z-direction nodal force output. With *DATABASE_NODAL_FORCE_GROUP resultant force output is defined. Example 4.4 from LS-Dyna training class NVH, Fatigue and Frequency Domain Analysis with LS-DYNA by Yun Huang.
FRF of a plate with pressure
This example shows how to use *FREQUENCY_DOMAIN_FRF for a plate with pressure excitation. Example 4.5 from LS-Dyna training class NVH, Fatigue and Frequency Domain Analysis with LS-DYNA by Yun Huang.
SSD with a rectangular plate
An example of a rectangular plate shows how to set up keywords for steady state dynamic (SSD) problems and how to start post-processing with *DATABASE_FREQUENCY. Example 5.1 from LS-Dyna training class NVH, Fatigue and Frequency Domain Analysis with LS-DYNA by Yun Huang.
SSD with base and enforced motion
This sequence of two examples shows how to set up an input file for large mass method. In the first file a rectangular plate is computed with base acceleration using *FREQUENCY_DOMAIN_SSD. In the second file for the same structure large mass method is applied with keywords *CONTROL_FREQUENCY_DOMAIN, *ELEMENT_MASS_NODE_SET and *BOUNDARY_SPC. Example 5.2 from LS-Dyna training class NVH, Fatigue and Frequency Domain Analysis with LS-DYNA by Yun Huang.
SSD with a wheel rim
This example shows how to run SSD for an industrial problem. A wheel rim model with base acceleration excitation is analysed. Example 5.3 from LS-DYNA training class NVH, Fatigue and Frequency Domain Analysis with LS-DYNA by Yun Huang.
ERP for a simplified engine model
This is a simplified engine model with base acceleration. It shows how to run equivalent radiated power (ERP) problems with *FREQUENCY_DOMAIN_SSD_ERP and how to postprocess with *DATABASE_FREQUENCY_BINARY_D3SSD. Example 5.4 from LS-Dyna training class NVH, Fatigue and Frequency Domain Analysis with LS-DYNA by Yun Huang.
Fatigue analysis based on SSD
This is a simplified bumper model with base acceleration. It shows how to fatigue analysis for sine sweep testing with *FREQUENCY_DOMAIN_SSD_FATIGUE and how to postprocess with *DATABASE_FREQUENCY_BINARY_D3SSD and *DATABASE_FREQUENCY_BINARY_D3FTG. Example 5.5 from LS-Dyna training class NVH, Fatigue and Frequency Domain Analysis with LS-DYNA by Yun Huang.
Random vibration with pressure load
This is an example of of random vibration with pressure load. A rectangular plate is subjevted to power spectral density load. *DATABASE_FREQUENCY_ASCII_NODOUT_PSD, *DATABASE_FREQUENCY_ASCII_ELOUT_PSD and *DATABASE_FREQUENCY_BINARY_D3PSD are used for post-processing of the results. Example 6.1 from LS-Dyna training class NVH, Fatigue and Frequency Domain Analysis with LS-DYNA by Yun Huang.
Cantilever beam I
This is a first example of a cantilever beam with concentrated mass subjected to power spectral density. *DATABASE_FREQUENCY_BINARY_D3PSD and *DATABASE_FREQUENCY_BINARY_D3RMS are defined to get output. Example 6.2 from LS-Dyna training class NVH, Fatigue and Frequency Domain Analysis with LS-DYNA by Yun Huang.
Cantilever beam II
This is a second example of a cantilever beam subjected to power spectral density. Gravity is used for acceleration. *DATABASE_FREQUENCY_BINARY_D3PSD and *DATABASE_FREQUENCY_BINARY_D3RMS are defined to get output. Example 6.3 from LS-Dyna training class NVH, Fatigue and Frequency Domain Analysis with LS-DYNA by Yun Huang.
Random vibration with thermal preload I
This is an example of a L-shaped panel subjected to random vibration with thermal preload. The first file shows the usual setup without preload. *INTERFACE_SPRINGBACK_LSDYNA is used to create a dynain-file, which is then the basis for pre-stress analysis with *INCLUDE. In addition, usage of intermittent eigenvalue analysis is shown. In the file domgeom.k the domain decomposition can be studied. Example 6.4 from LS-Dyna training class NVH, Fatigue and Frequency Domain Analysis with LS-DYNA by Yun Huang.
Random vibration with thermal preload II
This is an example of a L-shaped panel subjected to random vibration with pressure preload. The first file shows the usual setup without preload. *INTERFACE_SPRINGBACK_LSDYNA is used to create a dynain-file, which is then the basis for pre-stress analysis with *INCLUDE. In addition, usage of intermittent eigenvalue analysis is shown. In the file domgeom.k the domain decomposition can be studied. Example 6.5 from LS-Dyna training class NVH, Fatigue and Frequency Domain Analysis with LS-DYNA by Yun Huang.
A tube model
This is an example of a tube model under nodal force power spectral density excitation. *DATABASE_FREQUENCY_BINARY_D3PSD and *DATABASE_FREQUENCY_BINARY_D3RMS are used for post-processing of the results. Example 6.6 from LS-Dyna training class NVH, Fatigue and Frequency Domain Analysis with LS-DYNA by Yun Huang.
A mass-spring model
This is an example of a mass-spring model under base acceleration power spectral density excitation. *DATABASE_FREQUENCY_BINARY_D3PSD and *DATABASE_FREQUENCY_BINARY_D3RMS are used for post-processing of the results. Example 6.7 from LS-Dyna training class NVH, Fatigue and Frequency Domain Analysis with LS-DYNA by Yun Huang.
Correlated multiple nodal forces
This is an example of a L-shaped panel subjected to multiple nodal force power spectral density excitation. *DATABASE_FREQUENCY_BINARY_D3PSD and *DATABASE_FREQUENCY_BINARY_D3RMS are used for post-processing of the results. The effect of correlated and uncorrelated excitations can be compared. Example 6.8 from LS-Dyna training class NVH, Fatigue and Frequency Domain Analysis with LS-DYNA by Yun Huang.
An aluminium bracket
This is an example of an aluminium bracket subjected to base excitation. Random fatigue analysis is running with *FREQUENCY_DOMAIN_RANDOM_VIBRATION_FATIGUE using Steinberg's three band method. *DATABASE_FREQUENCY_BINARY_D3FTG, *DATABASE_FREQUENCY_BINARY_D3PSD and *DATABASE_FREQUENCY_BINARY_D3RMS are used for post-processing of the results. Example 7.1 from LS-Dyna training class NVH, Fatigue and Frequency Domain Analysis with LS-DYNA by Yun Huang.
An aluminium beam
This is an example of an aluminium beam with pre-determined notch subjected to base acceleration excitation. Random fatigue analysis is running with *FREQUENCY_DOMAIN_RANDOM_VIBRATION_FATIGUE using Dirlik's method. *DATABASE_FREQUENCY_BINARY_D3FTG, *DATABASE_FREQUENCY_BINARY_D3PSD and *DATABASE_FREQUENCY_BINARY_D3RMS are used for post-processing of the results. Example 7.2 from LS-Dyna training class NVH, Fatigue and Frequency Domain Analysis with LS-DYNA by Yun Huang.
BEM acoustics of a rectangular plate I
This is a first example of a recangular plate subjected to nodal force excitation. *FREQUENCY_DOMAIN_ACOUSTIC_BEM is used for running a vibro-acoustic problem with variational indirect BEM. In the file domgeom.k the domain decomposition can be studied. Example 8.1 from LS-Dyna training class NVH, Fatigue and Frequency Domain Analysis with LS-DYNA by Yun Huang.
BEM acoustics of a rectangular plate II
This is a second example of a recangular plate subjected to nodal force excitation. *FREQUENCY_DOMAIN_ACOUSTIC_BEM is used for running a vibro-acoustic problem with Rayleigh Method. Example 8.2 from LS-Dyna training class NVH, Fatigue and Frequency Domain Analysis with LS-DYNA by Yun Huang.
BEM acoustics of a rectangular plate III
This is a third example of a recangular plate subjected to nodal force excitation. *FREQUENCY_DOMAIN_ACOUSTIC_BEM is used for running a vibro-acoustic problem with Kirchhoff Method. Example 8.3 from LS-Dyna training class NVH, Fatigue and Frequency Domain Analysis with LS-DYNA by Yun Huang.
BEM acoustics of a beam subjected to SSD
A rectangular beam is subjected to frequency domain acceleration. BEM acoustic analysis is coupled with SSD excitation via *FREQUENCY_DOMAIN_SSD. *FREQUENCY_DOMAIN_ACOUSTIC_BEM uses variational indirect BEM and raised cosine windowing technique for FFT. In the file domgeom.k the domain decomposition can be studied. Example 8.4 from LS-Dyna training class NVH, Fatigue and Frequency Domain Analysis with LS-DYNA by Yun Huang.
BEM acoustics of a simple car model
A simplified car model is subjected to SSD nodal force excitation. BEM acoustic analysis is coupled with SSD excitation via *FREQUENCY_DOMAIN_SSD. *FREQUENCY_DOMAIN_ACOUSTIC_FRINGE_PLOT_SPHERE is used to visualize noise distribution. Example 8.5 from LS-Dyna training class NVH, Fatigue and Frequency Domain Analysis with LS-DYNA by Yun Huang.
BEM acoustics of a tunnel model
A simplified tunnel model is subjected to a user defined velocity excitation. *FREQUENCY_DOMAIN_ACOUSTIC_BEM_PANEL_CONTRIBUTION is used for running acoustic panel contribution analysis with variational indirect BEM. Example 8.6 from LS-Dyna training class NVH, Fatigue and Frequency Domain Analysis with LS-DYNA by Yun Huang.
BEM acoustics of a simplified compartment model
A simplified auto compartment model is analysed. For FFT, windowing technique raised cosine is used. Differences between collocation BEM and variational indirect BEM can be studied. Example 8.7 from LS-Dyna training class NVH, Fatigue and Frequency Domain Analysis with LS-DYNA by Yun Huang.
BEM acoustics of a box with impedance condition
An example of a box shows how to set up an impedance condition. Collocation BEM with different boundary conditions is used Example 8.8 from LS-Dyna training class NVH, Fatigue and Frequency Domain Analysis with LS-DYNA by Yun Huang.
BEM acoustics of a pulsating sphere in half space
This example of a pulsating sphere in half-space shows how to set up reflection conditions with *FREQUENCY_DOMAIN_ACOUSTIC_BEM_HALF_SPACE. In the files domgeom.k the domain decompositions can be studied. Example 8.9 from LS-Dyna training class NVH, Fatigue and Frequency Domain Analysis with LS-DYNA by Yun Huang.
BEM acoustics with acoustic transfer vector I
This example shows how to set up an acoustic transfer vector (ATV) computation with *FREQUENCY_DOMAIN_ACOUSTIC_BEM_ATV and how to post-process with *DATABASE_FREQUENCY_BINARY_D3ATV. In the file domgeom.k the domain decomposition can be studied. Example 8.10 from LS-Dyna training class NVH, Fatigue and Frequency Domain Analysis with LS-DYNA by Yun Huang.
BEM acoustics with acoustic transfer vector II
This example shows how to set up an modal acoustic transfer vector (MATV) computation with *FREQUENCY_DOMAIN_ACOUSTIC_BEM_MATV and how to run several loading cases on SSD with *CASE. Post-processing is done with *DATABASE_FREQUENCY_BINARY_D3SSD. Example 8.11 from LS-Dyna training class NVH, Fatigue and Frequency Domain Analysis with LS-DYNA by Yun Huang.
BEM acoustics with incident wave
An example of acoustic pressure scattered from a rigid spherical surface shows how to solve acoustiv scattering problems with *FREQUENCY_DOMAIN_ACOUSTIC_BEM and *FREQUENCY_DOMAIN_ACOUSTIC_INCIDENT_WAVE. Example 8.12 from LS-Dyna training class NVH, Fatigue and Frequency Domain Analysis with LS-DYNA by Yun Huang.
FEM acoustics of a simplified compartment model I
This is an example of a simplified compartment model with hexaeder elements and velocity boundary conditions. It is shown how to set up a model for frequency domain FEM acoustics with *FREQUENCY_DOMAIN_ACOUSTIC_FEM and how to post-process with *DATABASE_FREQUENCY_BINARY_D3ACS. Results can be compared with the example ''BEM acoustics of a simplified compartment model''. Example 9.1 from LS-Dyna training class NVH, Fatigue and Frequency Domain Analysis with LS-DYNA by Yun Huang.
FEM acoustics of a simplified compartment model II
This is an example of a simplified compartment model with tetrahedal elements. It is shown how to set up a model for frequency domain FEM acoustics with *FREQUENCY_DOMAIN_ACOUSTIC_FEM and how to post-process with *DATABASE_FREQUENCY_BINARY_D3ACS. Results can be compared with the example ''BEM acoustics of a simplified compartment model'' and ''FEM acoustics of a simplified compartment model I''. Example 9.2 from LS-Dyna training class NVH, Fatigue and Frequency Domain Analysis with LS-DYNA by Yun Huang.
FEM acoustics of a simple box model with SSD
This is a simple box model to show how to couple FEM acoustics with steady state dynamics (SSD). Example 9.3 from LS-Dyna training class NVH, Fatigue and Frequency Domain Analysis with LS-DYNA by Yun Huang.
FEM acoustics with Impedance boundary conditions
A simple cabin model with seats shows how to set up multiple boundary conditions and how to define impedance boundary conditions. Example 9.4 from LS-Dyna training class NVH, Fatigue and Frequency Domain Analysis with LS-DYNA by Yun Huang.
Response spectrum analysis of a simple block model
This example shows how to set up a simple brick tower model to run resonse spectrum analysis with *FREQUENCY_DOMAIN_RESPONSE_SPECTRUM. *DEFINE_CURVE and *DEFINE_TABLE are used to define ground acceleration spectra for different damping coefficients. Post-processing is done with *DATABASE_FREQUENCY_BINARY_D3SPCM. Example 10.1 from LS-Dyna training class NVH, Fatigue and Frequency Domain Analysis with LS-DYNA by Yun Huang.
Response spectrum analysis of a simplified multi-story building model
This example shows how to run resonse spectrum analysis with *FREQUENCY_DOMAIN_RESPONSE_SPECTRUM for a simplified multi-story building model with shells and beams. *DEFINE_CURVE and *DEFINE_TABLE are used to define ground acceleration spectra for different damping coefficients. Post-processing is done with *DATABASE_FREQUENCY_BINARY_D3SPCM and *DATABASE_NODAL_FORCE_GROUP. Example 10.2 from LS-Dyna training class NVH, Fatigue and Frequency Domain Analysis with LS-DYNA by Yun Huang.
Simple break
This is a simple break example to show how to set up break squeal problems. A multi-step method with intermittent eigenvalue analysis using *CONTACT_AUTOMATIC_SURFACE_TO_SURFACE_MORTAR_ID, *CONTROL_IMPLICIT_EIGENVALUE, *CONTROL_IMPLICIT_ROTATIONAL_DYNAMICS and *CONTROL_IMPLICIT_SOLVER is presented. Example 11.1 from LS-Dyna training class NVH, Fatigue and Frequency Domain Analysis with LS-DYNA by Yun Huang.
Square tube
This is a sequence of problems for running problems with IGA. The first example shows steady state dynamics (SSD) with IGA, *ELEMENT_SHELL_NURBS_PATCH is used to define a shell nurbs element. The second example combines periodical load with IGA. In the third example, results can be compared with classical FEA. Examples 11.2-11.4 from LS-Dyna training class NVH, Fatigue and Frequency Domain Analysis with LS-DYNA by Yun Huang.
Square bar
This is an example for running problems with IGA. Results can be compared with classical FEA. Examples 11.5-11.6 from LS-Dyna training class NVH, Fatigue and Frequency Domain Analysis with LS-DYNA by Yun Huang.