On the Feasibility of Multi-kHz Acquisition Rate Tomographic-PIV in Turbulent Flames
Abstract
Tomographic particle image velocimetry (tomographic-PIV) is a recently developed measurement technique used to acquire volumetric velocity field data in liquid and gaseous flows. The technique relies on line-of-sight reconstruction of the rays between a 3D particle distribution and a multi-camera imaging system. In a turbulent flame, however, index-of-refraction changes resulting from local heat-release may inhibit reconstruction and thereby render the technique infeasible. The objective of this study was to test the efficacy of tomographic-PIV in a turbulent flame. An additional goal was to determine the feasibility of acquiring usable tomographic-PIV measurements in a turbulent flame at multi-kHz acquisition rates with current generation laser and camera technology. To this end, a setup consisting of four CMOS cameras and a dual-cavity Nd:YAG laser was implemented to test the technique in a lifted turbulent jet flame. While the cameras were capable of kHz-rate image acquisition, the laser operated at a pulse repetition rate of only 10 Hz. However, use of this laser allowed exploration of the required pulse energy and thus power for a kHz-rate system. The imaged region was 29 28 2.7mm in size. The tomographic reconstruction of the 3D particle distributions was accomplished using the multiplicative algebraic reconstruction technique. The results indicate that high quality tomographic-PIV measurements in a turbulent flame are possible with laser pulse energies of 25mJ, which is well within the capability of current-generation kHz-rate diode-pumped solid state lasers.
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 01, 2013
- Accession Number
- ADA587685
Entities
People
- Isaac Boxx