Session: 30-14 Turbines 3 and Fluids 2

Submission Number: 175618

Velocity Flow Field Measurement of Near Supercritical CO2 Using Backlight PIV 

This paper shows the successful implementation of a backlight particle image velocimetry (PIV) technique to visualize and quantitatively study the high-pressure liquid CO₂ flow field within a channel. Our strategy employed a micro-PIV 2D2C (Two-Directional, Two-Component) approach, leveraging high-speed camera imaging and advanced cross-correlation methods to measure the instantaneous velocity vectors from the flow field. For enabling robust flow visualization under challenging conditions, liquid CO₂ was seeded with silver-coated hollow glass microspheres. The tracer particles, sized from 5 to 30 microns, were specifically selected for high reflectance and robustness against high-pressure levels during tracing of the fluid's motion precisely. In addition, these are the sole tracers available to be applied to this method for studying the CO₂ flow under supercritical thermodynamic conditions because of the high density variations at higher pressure values.

The experimental equipment was well designed, comprising a CO₂ flow manifold for precise fluid supply, a K-type thermocouple for precise measurement of the temperature, and digital pressure transducers for control and measurement of the thermodynamic state of the system. One of the innovations is the application of a backlight illumination setup, which forms high-contrast particle shadows to be measured. This technique provides high-resolution velocity information while minimizing the laser-induced heating effects and is therefore suitable for studying CO₂ flow dynamics near its critical and supercritical conditions. This study provides vital information about complex CO₂ flow behaviors, which can be helpful to study the heat transfer phenomena and validation of computational models.

Presenting Author: Ritesh Ghorpade University of Central Florida

Presenting Author Biography: Posdoctoral Scholar at University of Central Florida

Authors:

Ritesh Ghorpade University of Central Florida
Soroush Niazi University of Central Florida
Yoav Peles University of Central Florida
Subith Vasu University of Central Florida