Investigation of the Spray Characteristics of an Aluminized Gel Fuel with an Impinging Jet Injector

Kurzfassung

The spray characteristics of an aluminum particle containing gelled Jet A-1-based fuel has been investigated under ambient pressure and temperature conditions with a doublet like-on-like impinging jet injector setup. A detailed parametric study concerning jet exit velocity and impingement angle has been conducted using shadowgraphy for the visualization of the topology of the atomization process and Fraunhofer diffraction for droplet size analysis. The atomization behavior has also been compared with the un-metallized gelled Jet A-1 fuel. The general features of the atomization behavior of the metallized and the non-metallized gelled fuels in an impinging jet injector setup are in principle similar to those of Newtonian fluids in broad parameter ranges at mean and larger Reynolds numbers, whereas ligaments and droplets are separated in bow-shaped structures from the sheet. For small jet-exit velocities, however, a ray-like pattern has been observed on the fluid sheet of the aluminized gelled fuel with its origin near the impingement point of both jets. Net-like structures occur at the rim of the liquid sheet, so that in this parameter region the breakup-process seems to be influenced by this rays-shaped pattern.