Sai Bhamidipati

 The journey of a thousand miles begins with a single step.

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This is beautiful. I've been wanting this combination of locomotion for a long time (Actually, since I was introduced to Tachikomas from Ghost in the Shell). This has much promise as it truly leverages the benefits of wheels (speed) with the stepping ability of legs. In my design, I would use mechanical brakes to lock the wheels while stepping/climbing etc. though. #ethzurich #roboticsystemslab #anymal #tachikoma #mobilerobots #engineering #software #locomotioncontrol https://lnkd.in/eMneXH2E

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****Beware of CFD "Influencers" on LinkedIn**** ****A Warning to Aspiring Students**** Recently, a disturbing trend has emerged on LinkedIn—self-proclaimed influencers in Computational Fluid Dynamics (CFD) promoting "wanna be CFD" courses for aspiring engineers, but at a significant personal profit. Some of these influencers charge upwards of $100 per course, or take a 50% cut from total sales, and unfortunately, this is little more than a get-rich-quick scheme disguised as education. ****Why is This Dishonest?**** Lack of Transparency: Many of these influencers market themselves as industry experts without showcasing real credentials or proven CFD experience. The pricing model is often hidden, and students only discover the hefty fees after investing their time and attention. Misleading Aspirants: These individuals prey on the enthusiasm and ambition of young engineers or professionals looking to build skills in CFD. The promise of exclusive knowledge is often paired with flashy marketing, but the actual content rarely justifies the high costs. Unproven Course Quality: Charging $100 per course or claiming 50% of total sales implies that the focus is more on profit than providing real value to students. The quality of the education often doesn’t match the premium price tag, leaving students with shallow knowledge and less money in their pockets. ****The Ethical Approach to Learning CFD**** There are many reputable sources of CFD knowledge that are affordable, transparent, and focused on student growth. Universities, professional training platforms, and open-source communities often provide courses designed by real experts at a fraction of the cost—or even for free. If you're serious about advancing your CFD skills, I urge you to be cautious and to: 1. Research the Instructor's Background: Ensure that your instructor has credible academic or industry experience. 2. Read Reviews & Testimonials: Look for honest feedback from past students. 3. Seek Value-Driven Education: Choose programs that offer clear learning outcomes, student support, and opportunities to engage with mentors. Don't let these money-focused influencers profit from your ambitions. Invest wisely in your education and be aware of those who are more concerned with their own wallets than your future. Stay sharp, stay ethical, and keep learning. PS: "I removed the name to avoid it sounding personal, though it was just meant to serve as an example."

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DMA is a great characterization tool to study rheology and measure the physical properties of solids and polymer melts. DMA involves applying a small, cyclic deformation to a sample and measuring its response to stress, temperature, frequency etc. DMA results exhibit change in storage modulus, loss modulus ans tan delta that are essential to identify Tg, Deformation under load and long term mechanical strength for various polymers used in industrial applications. Follow Jeffrey A. Jansen for more such insights.

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I am excited to share the results of my recent computational fluid dynamics (CFD) simulation using Large Eddy Simulation (LES) to analyze vortex shedding on a NACA 4412 airfoil. The simulation was conducted at a Mach number of 0.09 and an angle of attack of 13.87 degrees. In this study, LES provided detailed insights into the turbulent flow structures and vortex dynamics around the airfoil. The video below demonstrates the complex flow patterns and the shedding vortices that occur at these conditions. This analysis is crucial for understanding the aerodynamic performance and potential noise generation mechanisms of airfoils in various applications. Feel free to reach out if you have any questions or would like to discuss the findings further! #CFD #LES #Aerodynamics #NACA4412 #VortexShedding #AerospaceEngineering

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Unveiling the Aerodynamic Shift: A Look Back at 2000's Cars and Their Impact on Today's Designs Imagine a time before today's sleek, fuel-efficient vehicles. The 2000's were a turning point in automotive design, with a growing emphasis on aerodynamics. My recent study, conducted using Simcenter Star-CCM+ software in TANSAM Center of Excellence powered by Siemens a government initiative by TIDCO , specifically focused on the lift and drag forces of the cars manufactured during that era. This research is not just about the past; it is about understanding the foundation for the aerodynamic advancements shaping the industry today. Key Findings and Their Lasting Influence: The Streamlining Revolution: The study identified a shift towards car designs with lower drag coefficients. This focus on streamlining, achieved through techniques like tapered rooflines and underbody panels, reduced air resistance, leading to improved fuel efficiency and higher top speeds. These principles continue to be core tenants of modern aerodynamic design. The Balancing Act: Lift vs. Drag: While minimizing drag is crucial, the research also highlighted the importance of managing lift. Excessive lift can compromise handling and stability. The findings from the 2000's cars provide valuable insights into achieving the optimal balance between these two forces, knowledge that informs the development of safe and efficient vehicles today. The automotive industry is constantly evolving. In TANSAM Center of Excellence we are eager to connect with #Industries, #OEM's to delve deeper into the fascinating world of aerodynamics. Let's leverage the knowledge of the past to propel us towards a future of efficient, sustainable, and exhilarating vehicles. #automotive #aerodynamics #SimcenterStarCCM #collaboration #futureofmobility #audi #BMW #MercedesBenz #Engineering

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⚙️ 𝗗𝗼 𝘆𝗼𝘂 𝗸𝗻𝗼𝘄 𝗵𝗼𝘄 𝘁𝗼 𝗷𝗼𝗶𝗻 𝘁𝗵𝗲 𝗱𝗶𝗳𝗳𝗲𝗿𝗲𝗻𝘁 𝗽𝗮𝗿𝘁𝘀 𝗼𝗳 𝗮 𝗡𝗔𝗦𝗧𝗥𝗔𝗡 𝗺𝗼𝗱𝗲𝗹? The most used joints by far are RBE2 and RBE3. You better not confuse them. I still remember my early days with NASTRAN—when I made a rookie mistake confusing RBE2 and RBE3 elements. Trust me, it wasn’t pretty, I ended up paying with 8 days of my holidays! 🔧 𝗥𝗕𝗘𝟮 𝘃𝘀. 𝗥𝗕𝗘𝟯: 𝗪𝗵𝗮𝘁’𝘀 𝘁𝗵𝗲 𝗗𝗶𝗳𝗳𝗲𝗿𝗲𝗻𝗰𝗲? •   𝗥𝗕𝗘𝟮 (Rigid Body Element 2): RBE2 elements create a rigid connection between nodes. They force all connected nodes to move together as a single rigid body. Mathematically you force the movement of several nodes (dependent) to move like the central node (independent). This is perfect when you need to simulate a stiff connection, like attaching a bracket to a structure. But be careful—using RBE2 can overly stiffen your model and lead to unrealistic stress concentrations. •   𝗥𝗕𝗘𝟯 (Rigid Body Element 3): Unlike RBE2, RBE3 elements distribute loads in a more flexible way, without adding stiffness to the model. Mathematically the move of the central node (dependent) is the weighted average of several nodes (independent). They’re ideal for simulating connections where you want to distribute loads across multiple nodes, like attaching a force to a surface area. RBE3 is great for maintaining realistic deformation while still accurately representing load distribution. 🔍 𝗟𝗲𝘀𝘀𝗼𝗻 𝗟𝗲𝗮𝗿𝗻𝗲𝗱: Each has its place in structural modeling—RBE2 for rigid connections and RBE3 for flexible load distributions. Understanding when to use each is key to accurate simulations. #Engineering #FiniteElementAnalysis #NASTRAN #StructuralAnalysis #RBE2 #RBE3 (*) Image credit: Nader Zamani in his Youtube channel

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CFD never ceases to amaze me. I give you Exhibit A. The filling of a subcritical parahydrogen tank is simulated with CONVERGE. This uses an equilibrium two-phase diffuse interface approach with tabulated fluid properties based on a Helmholtz equation of state for parahydrogen in REFPROP. Cold liquid parahydrogen enters the tank from the bottom at 20 K and approximately 2 bar. The two-phase region is modeled at equilibrium with all mixture properties evaluated directly from the equation of state and surface tension forces at the phase interface. The video shows cut-planes colored by vapor volume fraction, vapor mass fraction, temperature, mixture cv, velocity magnitude, and phase indicator flag (1=liquid, 2=two-phase liquid/vapor mixture, 3=vapor). Thanks to David Rowinski for this bleeding edge CONVERGE simulation. #cfd #convergecfd #hydrogen

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Hardware struggles are a real pain when it comes to complex analysis. As #CAE Engineers, waiting hours for a simulation to run, only for it to crash due to memory limits, is frustrating. 😤 Upgrading systems feels like a dream, but deadlines won’t wait. ⌚ Here’s to engineers' perseverance & patience that help them solve problems. #CAEwithAbhinav #EngineeringLife #problemsolving Join our thriving community of CAE experts on WhatsApp - Link in comment👇 My Physics Cafe

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Excited to share my latest project: a bearing housing assembly created in Fusion 360! This step-by-step video walks through the design, assembly, and final setup of the housing, showcasing how 3D modeling can streamline mechanical projects. From positioning the bearings to aligning components, it’s all about precision and efficiency. Check it out and let me know what you think! #Fusion360 #MechanicalDesign #Engineering #3DModeling #BearingHousing #CAD"

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Took this picture as a YouTube cover, and I think it's worth sharing it here. Here is my place of joy and science, I learned and discovered many things in this place. https://lnkd.in/dfgvqaGn #additivemanufacturing #metamaterials

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🌔 Going to the Moon? 🌖 You’re going to have to Model and Simulate your systems, especially when its your first time back in a while! In his MATLAB EXPO talk, Hector Hernandez describes how NASA modeled the electrical power system of Orion with the Spacecraft Power Capability (SPoC) tool using MATLAB, Simulink, and Simscape. This was a key enabler of Artemis I and will be used to support Artemis II and future missions. Check out the talk titled “NASA’s Spacecraft Power Capability Model and Applications Using MATLAB” and any other MATLAB EXPO talk you may have missed with the link in the comment below 👇 #NASA #MATLABEXPO #ToTheMoon

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My Journey with CFD It all began in 2003, during my undergraduate studies, when I was first introduced to computational fluid dynamics (CFD). My fascination sparked while working on my final year project, where I used Fluent 6.0 to tackle the complexities of rotating turbomachinery fluid flow. That initial experience ignited a passion that would shape my career. In 2004, I embarked on my professional journey, stepping into the world of Star CD 3.1. It was a challenging transition; mastering this intricate CFD code was no small feat. I found myself navigating various UNIX and Linux systems, including powerful SGI and HP-UX supercomputers, all while conducting simulations via full UNIX commands. During this time, I was immersed in a range of complex problems, from vehicle thermal management simulations to moving mesh scenarios for internal combustion engines and general fluid flow analyses. As the years progressed, I witnessed a significant shift in the industry. In 2007, I embraced the launch of Star CCM+, a software that marked a turning point towards user-friendly, object-oriented platforms. This change mirrored the broader trends in CFD as CD Adapco merged with MSC Software to better compete with Fluent, which had joined forces with ANSYS. The lines between CFD and finite element analysis began to blur, leading to the rise of integrated CAE solutions. However, as the landscape evolved, I felt a growing disconnect with my current role. In search of renewed passion, I made the bold decision to leave my former employer and join SIRIM. This move proved transformative. At SIRIM, I was given the opportunity to establish a strong CFD presence within the company, allowing me to explore the software's capabilities in depth. Since 2009, I have worked on a variety of simulations, ranging from basic fluid flow to advanced multiphase flows, including the intricate Rosin-Rammler droplet distribution. My work has had a tangible impact. I collaborated with architects, providing crucial insights for high-rise design decisions. I assisted mechanical and electrical engineers in developing efficient HVAC systems, and I helped plant managers enhance power generation efficiency while reducing costs associated with critical asset replacement. Looking back, CFD has been more than just a professional tool; it has been a lifelong passion. As I reflect on my journey, I am excited about the next 20 years ahead, ready to further deepen my expertise and contribute to the field I love. If you’re curious to learn more about my experiences or the world of CFD, I would be more than happy to share.

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🔴 Struggling with problem-solving in engineering, physics, or math? ♟️ Here’s a powerful strategy to transform your textbook study sessions. When you tackle textbook problems with available solutions, don’t rush! Spending just 3-5 minutes before peeking at the solution may short-circuit your learning. Here’s why: Effective problem-solving requires building on fundamental principles rather than relying on matching problems to examples you’ve seen before. Instead: ↳ Take the time to explore each problem from first principles. ↳ Study examples to understand the underlying concepts and applications, and then set them aside. Avoid trying to match your problem to an example—this is about building a deeper understanding, not just finding similar cases. ↳ Approach each problem as a unique challenge, staying with it longer before seeking answers. This lets you apply principles independently and strengthens critical thinking skills. This approach demands patience and focus, but it’s the foundation for mastering engineering, physics, and math at a high level. This strategy will lead to deep, focused learning and understanding! Good luck! 🍀 If you found this useful, consider sharing ♻️, and leave your thoughts in the comments below. Thanks!

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✨️Are you interested in optimizing energy absorption in auxetic structures?✨️ 📢 My latest research, titled "Mechanical Behavior of Graded Combined Auxetic-Honeycomb Structures" published in [International Journal of Mechanical Sciences] explores how to significantly improve energy absorption in auxetic structures using a combination of grading techniques and reinforced cores. This is particularly relevant for applications in various industries and sports.🏸🎿👟 📝The study investigates different methods of grading the combined auxetic-honeycomb structures, including graded angles and thickness variations. It also explores the impact of adding a reinforced core (RCA) to further enhance energy absorption. The results show that unilateral graded angle structures with RCA offer the highest energy absorption, exceeding traditional designs by up to three times. This research offers valuable insights for designing high-performance energy absorbers. You can find the full article (with free access for a limited time) by following the link in the comments below! https://lnkd.in/gT4MmBnq https://lnkd.in/gk_KzcZA #auxetic #honeycomb #energy_absorption #graded_structure #combined_structure #additive_manufacturing

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Every aspiring engineer needs powerful resources, and that’s what we provide at Lucid! 📚 Follow us to get the latest courses and academic tips. 💡 #EngineeringStudents #Lucid #LearningOpportunities

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💡 Solving Snap-Back in #FEA: A Control Load Approach 💡 Last week I talked about two of the most common instability problems that we face in FEA: ➡️ Snap-through, which is commonly addressed by switching to displacement-control. 👍 ➡️ Snap-back, which is a %@£-$€! pain in most cases 😨 Snap-back instabilities can turn any simulation into a complex challenge, often crashing the analysis. What can we do when this happens? 😭 💡 A few years ago I stumbled upon the #Phd thesis of an old friend and top researcher in the field of materials simulation, Javier Segurado, where he described a general method based on tracking a degree of freedom that increases monotonically throughout the simulation. The selection of this "control degree of freedom" is crucial and the success of this strategy fully depends on it. In #fracturemechanics, a variable that often increases monotonically is the crack opening displacement. We can use the COD as the control variable, which will be used to guide the solver through the load-displacement path. This method also requires 2 custom finite elements which are defined by constant stiffness matrices. Here’s how it works: 🔹 Create an auxiliary node, this will be the "driving node" (D) 🔹 Find a control variable. May be a single dof or multiple dofs from the model. For instance, the COD is the relative displacement between 2 nodes. 🔹 Create the first custom element (user element) with which we relate the reaction force at D with the control dof. So, the reaction force at D will be equal to the control dof (e.g. the COD). 🔹 Create the second custom element. In this case, the displacement of D is set equal to the force at the node where the load is applied in the model. 🔹 The final ingredient is to load the model. We do this applying a force to D (!). Sounds crazy but that is how we control the FE model, by monotonically increasing the COD. ✅ Following these instructions, you will be able to run stable models with snap-back without using artificial stabilization, riks, etc ! I have used it in several occasions, for instance to model crack propagation processes, post-buckling, fiber kinking... Shortly I will write a blog post with all the details and a few examples to put it in practice in #Abaqus (no subroutines required). 🔔 Subscribe to my Newsletter to be notified of this and many more FEA tips and recommendations that are coming soon! https://lnkd.in/ddD9-vCF #finiteelementanalysis

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I am excited to share that our manuscript titled “Adaptively remeshed multiphysical modeling of resistance forge welding with experimental validation of residual stress fields and measurement processes”, co-authored with colleagues from UC Davis, Sandia, and Los Alamos, was recently published in the International Journal of Solids and Structures. This paper is a step forward for modeling residual stresses of welded components, including both model predictions and validation with experimental measures. We introduce a novel multiphysical finite element model for a resistance forge weld, employing adaptive remeshing to enable Lagrangian simulation through the large deformations. The model’s predictions for residual stress, the primary QOI, are validated though comparison to three experimental measures: contour method, slitting method, and neutron diffraction. The model generally accords with the measurements, and we further probed the discrepancies by manipulating the model to replicate the destructive testing processes. Grateful for the opportunity to partner with University of California, Davis and Los Alamos National Laboratory collaborators on this -- I learned a bunch about residual stress measurement! The paper is available (open source) this month at IJSS through the following share link (https://lnkd.in/g-aUqy77), and it will be available next year through OSTI (https://lnkd.in/gdNKMUXt). Feel free to message me for a copy! co-author tags: Christopher D'Elia, Michael Hill, Bjørn Clausen, Chris San Marchi, Jay Foulk, Alex Hanson, Kevin Manktelow

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