Turbulence Generated by Sparse 3D Multi-Scale Grid EuHIT Funded Project

Team

Jacek Kopeć
University of Warsaw, Warsaw, Poland
Kamil Kwiatkowski
University of Warsaw, Warsaw, Poland
Nadeem A Malik
King Fahd University of Petroleum and Minerals, Dhahran, Saudi Arabia
Usama Muhammad Syed
King Fahd University of Petroleum and Minerals, Dhahran, Saudi Arabia
Jackson D. Tellez-Alvarez
Technical University of Catalonia, Barcelona, Spain

Overview

Research Infrastructure
Max Planck High-Turbulence Facility, Germany
Facilities used
Variable Density Turbulence Tunnel (GTF1)
Project leader
Jose M. Redondo
UPC BarcelonaTech, Barcelona, Spain

Abstract

We propose an experimental investigation of properties of turbulent flow generated by the new concept of a sparse three-dimensional multi-scale grid turbulence generator (3DSG), which is composed of self-similar (possibly fractal) layers of grids in co-planar arrangement, thus producing an overall blockage ratio which is substantially less than in a comparable 2D arrangement.

The study of previous fractal induced flows has not been able to study the intermittency (Spatial and Temporal) of the wakes of such devices; we aim to investigate these in this proposal. It is also important to compare higher order turbulence descriptors. This may lead to enhanced mixing efficiencies, reduced drag, and such like. The main goal of the project is to explore the properties of turbulence flow generated by 3DSG. The experimental data will be compared with data generated from traditional fractal grids, and also with theoretical and numerical calculations where possible.

High frecuency (hot wire) velocimetry will be used to compare higher order structure functions, and the scale to scale transfer within the fractal generated non-homogeneous wakes. The variation of the fractal dimension of the wakes of scalar or tracers (PIV, PT, dye, fog ), velocity and vorticity will be studied comparing the new and older (Square sequence, Sierpinski, etc..) grids.