Generac Power Systems
● Designed a functional elongated hexagonal perforated panel for an aesthetic look on the exteriors of the module
● Calculated the exhaust air thrust and performed FEA on different designed patterns on the exhaust manifold
● Designed a set of experiments to analyze the airflow simulation of 3d printed prototype on the exhaust
● Revamped the complete design of bracket assembly and simulated each component under varying load conditions
● Determined the fastener schedule for a different types of mounting surfaces and documented them
Generac Power Systems
● Designed a functional elongated hexagonal perforated panel for an aesthetic look on the exteriors of the module
● Calculated the exhaust air thrust and performed FEA on different designed patterns on the exhaust manifold
● Designed a set of experiments to analyze the airflow simulation of 3d printed prototype on the exhaust
● Revamped the complete design of bracket assembly and simulated each component under varying load conditions
● Determined the fastener schedule for a different types of mounting surfaces and documented them
Design and Finite Element Simulation of Meta-Cells with Pre-Stresses
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Designed a unit cell with varying pre-stress under uniaxial compression to analyze Von-Mises stress and energy absorption using ABAQUS.
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Compared the best possible case of pre-stressed symmetric and chiral unit cells to determine the model with the least von Mises stress and highest energy absorption.
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Analyzed the symmetric, chiral and achiral packed cell configuration under uniaxial compression and determined the effects of friction.
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Plotted the energy absorption curves to compare the effects of change in radii for the achiral models.
ABSTRACT
Mechanical metamaterials have surged in popularity due to their exceptional properties, drawing inspiration from tensegrity structures and their unique load bearing capacities. This innovation has led to the creation of novel mechanical metamaterials. These materials exhibit promising traits such as high resilience, impressive strength-to-volume ratio, and robust energy absorption.
The integration of pre-stress into mechanical metamaterials has been a pivotal focus, elevating their physical properties and potential applications. The concept of pre-stress involves inducing a specific state of stress and strain within a material, enhancing its ability to fulfill its intended function optimally. Materials endowed with pre-stress exhibit distinctive mechanical characteristics that render them particularly advantageous for energy absorption applications. Within the scope of my thesis work, I delved into an extensive exploration of two distinct unit meta-cell designs, meticulously simulating them both in 2D as individual units and as packed meta-cells. The unit cell designs encompass symmetric, and chiral configurations, along with their respective variations. My investigation initially involved a comprehensive comparison of all original designs, exploring various scenarios of pre-stress to ascertain the most optimal setting. Subsequently, the results depict the pre-stressed chiral designs, characterized by compression in horizontal bar and tension in vertical bar, as the most favorable scenario under vertical compression due to higher strengths and larger energy dissipation.
This investigation underscores the significant potential of incorporating pre-stress into mechanical metamaterials, particularly through the optimization of specific unit cell designs. The findings pave the way for the development of advanced materials with higher energy absorption, resilience, and strength-to-volume ratios, opening doors to diverse applications across various areas.
Simulation Results
Test Results
Conclusion
•The initial criteria for the comparison is having a same magnitude of σ11', σ22’ in the horizontal bar and vertical bar respectively.
•The maximum permissible buckling load is determined for the vertical bar under compression to determine the geometry of the model.
•Pre-stress has a little influence on the overall stiffness of the model in symmetric unit cell and the von-mises stress in the horizontal and vertical bar are lower for case 3 (compression-tension) compared to other cases.
•In the chiral unit cell case 3 (compression-tension) is the stiffest and has lower von-mises stress in both bars indicating higher strength of the bars in this particular scenario.
•Comparing the case 3 (compression-tension) for the chiral unit cell and symmetric cell, the chiral unit cell have higher stiffness and higher strength in the bars.
•When comparing the symmetric packed cell, chiral packed cell and achiral packed cell for all the five cases with and without friction, case 3 (compression-tension) is the stiffest and more compliant.
•When subjected to cyclic loading of load vs displacement curve for the symmetric packed cell, chiral packed cell and achiral packed cell the case 3 (compression-tension) has higher area under the hysteresis meaning higher energy dissipation and when compared among themselves the chiral packed cell have higher area.
•Comparing the load vs displacement for the anti-chiral packed cell with varying internal ring radii shown that with the increase in the internal ring radii the energy absorption reduces.