Xinxin Sun’s Post

Understanding how #water is absorbed in cement-based materials is essential for predicting the long-term #durability of #concrete structures. Conventional #numerical models simplify processes by averaging #material properties and flow variables. Such methodology fails to capture the complete #microscopic details of the relevant processes, and a more profound #fundamental understanding is needed. Our recent study investigated the capillary water #imbibition processes through #DirectNumericalSimulations (DNS) of air-water #multiphase flow, directly at the #pore level. This approach solves full microscopic flow equations using fine numerical #meshes to enable detailed insight into #porescale variables and processes that are still poorly understood. A number of different features were analysed using 2D #model geometries, such as changes in the pore-sectional area, cross-flow between capillaries of different radii, or the influence of narrow throats on imbibition #dynamics and air #trapping. Considering the importance of spontaneous imbibition in a broad range of #natural and #industrial processes, the knowledge we obtain here can improve our fundamental understanding and lead to the #development and #enhancement of #macroscale (i.e. traditional) models. To know more: https://lnkd.in/eXbr8QUe Luka Malenica Zhidong Zhang Ueli Angst

An important step in understanding liquid transport in porous materials' complex microstructure.

this is critical in predicting fluid behaviour thus critical in design of mixers

𝗔𝗱𝘃𝗮𝗻𝗰𝗶𝗻𝗴 𝘁𝗵𝗲 𝗳𝗶𝗲𝗹𝗱 𝗼𝗳 𝗖𝗙𝗗: 𝗳𝗹𝘂𝗶𝗱𝘀 𝗼𝗳 𝗰𝗼𝗺𝗽𝗹𝗲𝘅 𝗿𝗵𝗲𝗼𝗹𝗼𝗴𝘆 The Weissenberg effect, also known as rod climbing, is a phenomenon observed in rheology of complex fluids like polymers. This effect occurs when a viscoelastic material is subject to shear forces and rotation simultaneously. In the Weissenberg effect, a cylindrical rotating rod immersed in a viscoelastic material, such as a polymer melt or solution, starts climbing along its axis as shown in the video. From the paper: "The Weissenberg effect or rod climbing occurs due to the influence of normal stress differences in the variation of the pressure value in the radial direction. Therefore, the normal stresses may cause the total normal pressure to decrease in the radial direction (...)" Want to know the details about modeling and numerics? Have a look at this paper: https://lnkd.in/eiwVQe59 Enjoy! #CFD #simulation #technology #rheology #polymer #flow #engineering #CAE #community #sharingsiscaring Source: https://lnkd.in/eJ396FUW

📣 It is our great pleasure to share the good news — the Special Issue "Design, Manufacturing and Properties of Refractory Materials" of Materials (IF=3.4) has now been released as a book (Reprint)! 🔥 Refractory materials are crucial for industrial and civil development. Sharing knowledge on refractories is the only way to upgrade their quality. 🌎 The authors who contributed to this Reprint by sharing their state-of-the-art research are greatly acknowledged! 🔎 This Reprint covers 18 research papers, including 1 review. It immerses the reader into the latest developments in the technology of refractory materials. From the application of Artificial Intelligence and computer-aided methods, like machine learning or image analysis and the simulation of refractories’ properties and corrosion phenomena, to tailoring the properties of refractories to be more environmentally friendly, we aim to elucidate the current global trends and progress being made in refractories technology. This reprint has been created by world-recognized researchers, representing both academia and industry, striving jointly to make refractories safer and working for longer periods of time. Feel welcome to download and read the Reprint: https://lnkd.in/dU2kMDws Thank you once again for your effort and your invaluable contribution !!! 💚

**Random Update:** Recently, I’ve been exploring metallography, the study of the microstructure of metals. To my understanding, in order to gain a lucid view of a metal’s structure at a micro level, the metal must undergo a six-step process: 1. A metal specimen is cut and applied to a grinding wheel to create a flat surface. The grinding process also removes any surface deformities. 2. After the flat surface is created, the specimen is polished using finer polishing compounds until it has a mirror-like finish. This process further removes surface defects, including abrasions left from the grinding process. 3. Next, the polished specimen is cleansed using solvents like ethanol or acetone to remove contaminants that could interfere with the etching process. 4. The etching process begins. Etching is when the polished and cleansed metal is exposed to a chemical solution that attacks certain phases or constituents of the metal. The chemical solution (etchant) chosen and the duration of etchant exposure depend on the material undergoing observation and its specific features needing to be exposed. 5. After the etchant is applied to the metal sample over a specific period of time, it is then rinsed in water or another suitable solvent and dried to prevent over-etching the material. 6. The carefully prepped material is then placed under a microscope for observation. The etching process creates visible distinctions between different material phases or constituents, providing insight into its microstructural features. I provided a link to a brief YouTube video giving a visual of the entire process if you want to check it out. To learning, Harland G.

📢 Excited to Share Our Recent Research 📢 I'm really happy to share that I had the opportunity to co-author a research paper titled, "Experimental Study on Cryogenically Treated Tungsten Carbide End Mill Cutter by Taguchi Method and Response Surface Methodology," which has now been published in Nanoworld Journal. This work was done during my time at Vardhaman College of Engineering (VCEH) , Under the leadership of Dr. Vishnu Vardhan Mukkoti, we worked on improving CNC milling of P20 steel using cryogenically treated tungsten carbide tools. Our experiments explored the impact of different temperatures (-110°C, -150°C, and -175°C) on critical factors like cutting forces, material removal rate, surface finish, tool wear, and power consumption. We utilized both Taguchi and Response Surface Methodology to optimize the process variables, and it was fascinating to see how both methods produced very similar results. The tools treated at -175°C delivered the best overall performance! A big thank you to my fellow co-authors Dr. Deepak Kolar, Narendra Thummala, Rajesh Ambati, Mahit Godi and of course Dr. Vishnu Vardhan Mukkoti for leading this research effort. I'm proud to have been part of such a dedicated and talented team. Check out the full paper here: https://lnkd.in/g746gByK #Research #Engineering #CNC #MaterialsScience #Cryogenics #Manufacturing #Optimization #TaguchiMethod #RSM #TungstenCarbide #Innovation #EngineeringResearch #Teamwork #Published #AcademicResearch #vmeg #vardhamancollegeofengineering #NanoworldJournal

Excellent work by Dr. Qifang Hu, one of my first PhD graduate and now a Research Fellow in Swinburne University of Technology! This paper explores the use of shear thickening fluid (STF) to enhance the mechanical properties of lattice structures, which are known for their energy absorption capabilities but tend to have lower stiffness. By combining STF with new lattice structures, we found significant improvements in both stiffness and energy absorption. Factors such as strain rate, weight fraction of STF, and lattice cell size were investigated. We hope that these findings offer valuable insights for designing STF-filled lattice structures for practical applications. #STF #FluidFilledLattice #EnergyAbsorption #CriticalStrainRate #Stiffness

Behind the scenes of surface engineering. At the microscopic level, polishing is a complex combination of physics and chemistry. Alumina particles, often only microns in size, act like countless tiny scrapers, removing material at the atomic level. This process involves both mechanical abrasion and chemical reactions at the surface interface. Our advancements in alumina technology have produced particles with precisely controlled shapes and size distributions. These improvements provide incredible control over the polishing process, making it possible to produce surfaces with roughness measured in nanometers. Our specialized lines - Gilox, Rapol and P-Series - illustrate these advances, each offering unique performance characteristics designed to meet specific industry needs. As the demand for perfection increases, so does the sophistication of our polishing materials and techniques. The precision achieved is particularly notable in applications such as semiconductor manufacturing, where even small surface imperfections can lead to device failure. New polishing techniques are replacing solvent-based approaches, and there's growing interest in bio-derived abrasives. Our goal is to match the performance of traditional alumina while exploring innovative alternatives - a balance that will undoubtedly shape the future of the industry. #surfaceengineering #nanotechnology #materialscience #advancedmanufacturing

🔬 Excited to Share Our Latest Research! 🔬 I'm thrilled to announce that my first first-author research paper from my PhD journey, "Crafting Multifunctional Materials with Tailored Mechanical and Magnetic Properties by Solid-State Non-equilibrium Processing," has been published in the Journal of Minerals, Metals and Materials Society (JOM). This work highlights how we can develop aluminum matrix composites with strong mechanical and desirable magnetic properties using solid-state metalworking. Key Findings: - Developed an aluminum matrix composite with SmCo5 particles using mechanical stir-based extrusion. - Achieved excellent hard magnetic behavior with a large coercivity of 13.5 kOe. - Enhanced the mechanical strength of the composite while maintaining comparable ductility to the non-reinforced alloy. - Observed a bimodal distribution of magnetic particles and a refined microstructure due to nanoscale precipitates. A huge thank you to my advisor, Prof. Bharat Gwalani, for his unwavering support and mentorship throughout this journey. I’m also deeply grateful to all my co-authors and collaborators from Pacific Northwest National Laboratory (PNNL) and University of North Texas (UNT). This achievement is a testament to the power of teamwork and cross-institutional collaboration. 🙏 Check out the full paper here: https://lnkd.in/g2GWz-iz #MaterialsScience #Composites #Innovation #MagneticComposites #SolidStateProcessing #MetalMatrixComposites