Experimental analysis and measurement of turbulent interactions in ethanol spray

• Grant number: 21/01746-2
• Support Opportunities: Scholarships in Brazil - Master
• Start date: April 01, 2021
• End date: February 16, 2022
• Field of knowledge: Engineering - Mechanical Engineering
• Agreement: Peugeot Citroën
• Principal Investigator: Guenther Carlos Krieger Filho
• Grantee: Victor Cupola Ganino
• Host Institution: Escola Politécnica (EP). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Associated research grant: 13/50238-3 - Conceptual study of an advanced ethanol-fueled engine, AP.BIOEN.CPE

Abstract

The development of the energy matrix in Brazil was determined through a guideline on biofuel consumption by the Proálcool program created in 1975. For this reason, the improvement of combustion technology for this fuel has become fundamental, as it was the way chosen for the transition from fossil fuel consumption to clean energy. Fluid velocity measurement techniques are widely used, therefore, the project seeks to obtain the spatio-temporal coherence limits in measurements using PIV (Particle Image Velocimetry) through measurements at the same points with LDA (Laser Doppler Anemometer) and HWA (Hot-Wire Anemometer). These techniques are fundamental to extract information to understand the phenomenon of turbulence in sprays. The main objective is to advance the studies previously carried out on the subject, using the IESC (Isothermal Ethanol Spray Chamber) from the LETE laboratory of the Polytechnic School of USP. Measurements will be made with the PIV, LDA and HWA, and through the comparisons of the results it will be possible to identify the scale limit and its relationship with the parameters of the PIV instrument. In addition, an analysis will be made at the interface points between the spray and the air, known as the shear layer, which presents great difficulty in identifying between particle and drop. In addition, in the region close to the injector nozzle there is a high velocity gradient, so a greater number of measurements will be concentrated using LDA in that region. The expected result is to obtain the appropriate interrogation window for the study of turbulence in relation to the scales, taking into account the effective number of particles (for PIV and LDA measurements) and other factors. With this, it should be possible to identify the limit of the measurement scales of the PIV instrument, mainly in the regions of greater uncertainties. It will be try to create a procedure whose objective is to collect information from the PIV measurement and automatically return the main parameters that involve turbulence with the uncertainties involved. This study will be fundamental for future applications of the PIV technique associated with the study of turbulence for various branches of knowledge, being effective in contributions to research and to industry. (AU)