NCSI: High-end Visualization of Turbulent Events in Wall-bounded Flows

Status	Completed
Mentor Name	Guillermo Araya
Mentor's XSEDE Affiliation	XSEDE-allocation PI
Mentor Has Been in XSEDE Community	4-5 years
Project Title	High-end Visualization of Turbulent Events in Wall-bounded Flows
Summary	Turbulent boundary layers are mainly characterized by high Reynolds numbers, randomness, chaos and disparate range of turbulent length/time scales. Despite its chaotic behavior, investigation performed during the last six decades has conclusively demonstrated the presence of organized motions in turbulent boundary layers, so called coherent structures (CS). A coherent structure may be defined as a region or parcel of fluid where any fluctuating component of the flow is highly correlated with itself. These structures can be considered the building-blocks of turbulent boundary layers, and significant attention has recently been given to explanation of their creation, development and destruction. Therefore, this project involves time-dependent 3D scientific visualization of coherent structures and turbulent events from a Direct Numerical Simulation (DNS) database of spatially-developing turbulent boundary layers subject to streamwise favorable pressure gradient and crossflow jet by means of flow animation videos and a fully immersive approach or virtual reality (VR). The main purpose of the EMPOWER internship project will be to develop a post-processing code in C++ and Unity platforms with GPU capabilities in order to perform flow visualization in a virtual reality environment. In addition, Paraview and Blender software will be used for the creation of a series of videos to dynamically visualize turbulent events such as; a) streaky structure dynamics, b) streak breakups, c) turbulent bursts, d) symbiosis of streaks and streamwise vortices, and e) hairpin vortex dynamics. This is a continuation Spring-2018 EMPOWER internship project.
Job Description	The apprentice position is at the High Performance Computing and Visualization Lab (HPCVL) www.uprm.edu/hpcvl/ at the Dept. of Mechanical Engineering in the U. of Puerto Rico-Mayaguez (UPRM). The undergraduate student intern will work on a post-processing code in the area of C++ platform programming with GPU capabilities to mitigate the performance issues as well as with open source codes. The principal objectives/tasks of this internship can be summarized as follows: - Develop a C++ code for managing/reading a large database of Direct Numerical Simulation (DNS) related to accelerating spatially-developing turbulent boundary layers subject to a crossflow jet. - Obtain the corresponding .obj and .stl files readable in Blender and Unity software. - Perform 3D flow visualization by the HTC Vive virtual-reality headset. - Develop flow animation videos by means of Paraview and/or Blender.
Computational Resources	The DNS database is already stored in Ranch (TACC). These simulations were performed in Stampede under XSEDE computational allocation #TG-CTS170006. The intern will be set as a user of this account in order to get access to the TACC computational resources.
Contribution to Community
Position Type	Apprentice
Training Plan	The intern will initially receive training on fluid dynamics, turbulence, coherent structures, data management, Unix programming, data transfer, C++ and visualization tool kits at the HPCVL lab by the PI and other skilled students. The purpose of this position is to encourage students from underrepresented communities to pursue STEM careers at a graduate level.
Student Prerequisites/Conditions/Qualifications	This apprentice level position is opened for undergraduate students at the University of Puerto Rico-Mayaguez. Candidates should have basic knowledge on: Python, C++ programming, Linux and fluid mechanics. In addition, students should demonstrate independence to perform research and willingness to learn parallel computing and to use Blender/Paraview and Unity platforms. A skilled intern has already been identified.
Duration	Semester
Start Date	09/01/2018
End Date	12/31/2018