BEGIN:VCALENDAR VERSION:2.0 PRODID:-//wp-events-plugin.com//7.2.3.1//EN TZID:Asia/Kolkata X-WR-TIMEZONE:Asia/Kolkata BEGIN:VEVENT UID:30@cds.iisc.ac.in DTSTART;TZID=Asia/Kolkata:20240111T110000 DTEND;TZID=Asia/Kolkata:20240111T120000 DTSTAMP:20240108T080126Z URL:https://cds.iisc.ac.in/events/ph-d-thesis-defense-hybrid-cds-11-januar y-2024-an-arbitrary-lagrangian-eulerian-volume-of-fluid-method-for-free-su rface-and-floating-body-dynamics-simulation/ SUMMARY:Ph.D: Thesis Defense: HYBRID: CDS: 11\, January 2024 "An Arbitrary Lagrangian Eulerian Volume of fluid method for free surface and floating b ody dynamics simulation." DESCRIPTION:DEPARTMENT OF COMPUTATIONAL AND DATA SCIENCES\n\nPh.D. Thesis D efense (HYBRID)\n\n\n\nSpeaker : Mr. Bhatta Bhanu Teja\n\nS.R. Number :06- 02-00-10-12-12-1-09588\nTitle : "An Arbitrary Lagrangian Eulerian Volume o f fluid method for free surface and floating body dynamics simulation."\nR esearch Supervisor :Prof. Sashikumaar Ganesan\nDate &\; Time : January 11\, 2024 (Thursday)\, 11:00 AM\n\nVenue : The Thesis Défense will be hel d on HYBRID Mode\n\n# 102 CDS Seminar Hall /MICROSOFT TEAMS\n\n\n\nPlease click on the following link to join the Thesis Defense:\n\nMS Teams link\n \nhttps://teams.microsoft.com/l/meetup-join/19%3ameeting_OGE0ZDhlZTMtNTJhY y00NDg1LWJiY2EtNjk2ZWRjOWY1OWE3%40thread.v2/0?context=%7b%22Tid%22%3a%226f 15cd97-f6a7-41e3-b2c5-ad4193976476%22%2c%22Oid%22%3a%2283157d9d-c640-4c35- 856e-b22b4ab79e4e%22%7d\n\nABSTRACT\nThe floating body dynamics is treated as a Fluid-Structure Interaction (FSI) problem. A FSI problem is where th e forces from the fluid move/deform the interacting structure\, and the mo vement of the structure\, in turn\, influences the dynamics of fluid flow resulting in a coupled set of partial differential equations. The problem is especially challenging owing to the time changing nature of the domain and the presence of multiple interacting phases. These kind of time changi ng domain and multi physics problems are primarily dealt with moving domai n or fixed grid techniques. In the moving domain technique\, the governing equations are posed in the so called Arbitrary Lagrangian Eulerian (ALE) formulation. In ALE formulation\, the interfaces are resolved by the mesh and thus leads to very good mass conservation properties. But the method f ails when there are large topological changes\, such as mixing and splitti ng. This problem can be partly handled by fixed grid techniques where a sp ecial function is used to represent various phases\, but the method has it s drawbacks\, one of which is the interfaces cannot be represented precise ly and smears with time which leads to mass conservation problems and ofte n much finer mesh is needed to localize the interface. Also\, because of t he pure convection nature of the phase transport equation\, a naive/standa rd discretization results in undershoots and overshoots of the solution. S pecial stabilization schemes have to be used to suppress the oscillations. The aim of the thesis is to treat the floating structure as a rigid body to estimate its overall stability in free surface flows.\n\nFirst\, the pr oblem is posed in moving mesh or Arbitrary Lagrangian Eulerian framework. The motion of the free surface was captured. But the method failed to capt ure the dynamics of the floating structure when it is introduced. Fine tun ing the mesh yielded only incremental result. So the research focus was sh ifted to fixed grid techniques\, particularly the 'Volume of Fluid' (VoF) method. For the present problem\, we took a hybrid approach. The interface between the floating structure and surrounding fluid/s is treated in a La grangian way\, thus necessitating mesh movement\, and the fluid-fluid inte rface (in our case\, it can be considered as water-air) is captured by the VoF equation. As there is mesh movement\, the VoF equation was also posed in ALE form.\n\nAs the VoF equation is a pure convection equation\, a nai ve Galerkin discretization results in undershoots and overshoots in the so lution. The Streamlined Upwind Petrov Galerkin (SUPG) stabilization is use d to stabilize the VoF equation. The scheme is shown to give stable result s. The Finite element method is used to discretize the coupled set of part ial differential equations. The method is extensively discussed in a movin g mesh setting with various boundary conditions. The partitioned time step ping is used to march in time across phases\, and a fully implicit scheme is employed within each phase.\n\nFinally\, this hybrid ALE-NSE-VoF with S UPG stabilization scheme is shown to give stable results for extended time steps. The numerical results with both the formulations(ALE and VoF) are discussed. The simulations are carried out in distributed setting with Mes sage passing interface(MPI)\, and the speedup results are discussed as wel l.\n\n\n\nALL ARE WELCOME CATEGORIES:Events,Ph.D. Thesis Colloquium END:VEVENT BEGIN:VTIMEZONE TZID:Asia/Kolkata X-LIC-LOCATION:Asia/Kolkata BEGIN:STANDARD DTSTART:20230111T110000 TZOFFSETFROM:+0530 TZOFFSETTO:+0530 TZNAME:IST END:STANDARD END:VTIMEZONE END:VCALENDAR