Week - 3 Drop test Challenge

AIM; To perform a Drop test Simulation of a mobile phone on the rigid floor body with suitable keyword Parameters and plot the results from it.

PROCEDURE;

1. Import the given Drop_test_onlymesh.k File in to ls dyna GUI.
2. The File Only Consists of the nodes and elements of the Mobile phone and the floor shell plate.
3. To perform the Simulation, materials, Section, initial velocity, Contact Interface, Boundary conditions, and ther output following Must be Specified.
4. Give the material properties for the parts given.
5. Create the section for shells and solid property to the parts in the model.
6. Then after we need to give boundary conditions to the model.
7. Then we need to give the Data base for Binary D3plot and ASCII output results.
8. We need to request the output results from the solver.
9. Analyse the result from the solver.

GIVEN MODEL;

The model contains three parts.

Among them we need to delete the extra solid body.

CREATING MATERIALS;

• For creating the materials go to Model and Part>Keyword Manager > All> MAT > Select the Material card and define the material properties like mass density, Young's modulus, Poisson's ration, Yield point stress values for both the material cards.

• For this model assembly we use two material properties.
• The linear elastic material to the phone with an aluminium material and rigid material to ground floor with a steel property.

BOUNDARY CONDITIONS;

SPC

• go to Model and part deck >create entity>Bcs>spc.

• select the create ,where we have to pick the nodes of the bottom rigid body and constrained the xyz and rx ry rz axis of the body.
• Mention the node set id(NSID) and apply it.

INITIAL VELOCITY;

• go to Model and part deck >create entity>Initial>velocity.

The velocity of 7.5mm/ms is given to the mobile phone. As the phone is dropping along a negative z-direction so assign the value in the Vz(direction)= -7.5 mm/ms is given as initial velocity.

NODE LIST;

SECTION;

Section is used to create the proprtites of elements,element formulations and thickness of the particular model.

model > Keyword manager > section > solid.

Shell section:

• same as solid use used to create the section for shell elements are,
• model > Keyword manager > section > shell.
• specify the sectionid(SECID), element formulation and thickness.

PART;

To define a part we must have nodes, elements, sections and materials.

CONTACT;

• Automatic surface to surface
• The surface-to-surface contact interface is used for the simulation. The command used for creating the contact interface between them.
• Select the slave as phone and master as floor shell part .
• The more stiffer part is consider as master.

CONTROL;

• Control cards is used to set the Termination time for an simulation model.
• To set control card,Model >Keyword manager > control >Termination command is used. The simulation time is set to 5.00ms.

DATABASE;

Used for creating the output results for the model.

BinaryD3plot

Keyword Manager > Database >Binary D3plot >DT 0.1. It prints the Output file at each 0.1ms. The D3PLOT card gives animation view get the results in the post-processing data after the simulation.

ASCII

Go to Keyword Manager > Database >ASCII >GLSTAT and MATSUM.

GLSTAT which gives global energy data like Kinetic Energy, Internal Energy and other types of energy.

MODEL CHECKER;

Before Run the Model , we have to check the model to avoid Errors and Warnings in the part.

For model checker go to HELP Tab>click on Old to New and select the Model checker.

The von moises stress is created at 48N/M^2.

GLSTAT PLOT;

• In this plot we have plotted the Kinetic energy,Internal energy and Total energy.
• From the plot we can see that, when mobile impcat to the ground, we can see deflection in Both Kinetic energy and Internal energy.
• The Kinetic energy is started at the 2.5ms and slowly becomes reduced due to the internal energy produced by the floor ground . The Total energy is remaining constant throughout the process.

https://drive.google.com/file/d/1UyOYT_0-8q8Rn9GscbPCB2DrTsbF14wX/view?usp=sharing