Two-photon fluorescence and soft X-ray imaging techniques for analyzing atomizing sprays

Atomizing sprays are used for painting, coating, washing, cooling, inhaling medicines, applying chemicals, creating powders etc.

However, the most noticeable example of application is the injection of liquid fuel in combustion devices to generate the necessary mechanical power in trucks, ships, planes and other combustion devices.

When illuminating an atomizing spray using visible light, photons interact several times with the surrounding droplets inducing strong blurring and resulting in no visibility.The applicant has recently revealed the possibility for the detailed visualization of atomizing sprays with nearly no blur using two-photon laser-induced fluorescence (2p-LIF).

Additionally, it has been demonstrated that 2p-LIF can be combined with soft X-rays imaging using a laser-plasma accelerator.

While X-ray radiography indicates liquid mass distribution, 2p-LIF imaging allows high-contrast images, making the two approach highly complementary.

In this proposal, those two techniques will be used to further understand how atomizing sprays are being formed for realistic injection of bio-fuels, such as ethanol, methanol and bio-diesel.

A complete, accurate and reliable description of liquid breakups occurring in atomizing sprays will be provided and a comprehensive set of experimental data for various operating conditions will be provided.

Such unique data will be both analyzed using modern machine learning computing tools and shared with spray modelers to validate CFD codes.