Preface 1.General Considerations 2.Basic Processes in Atomization 3.Drop Size Distributions of Sprays 4.Atomizers 5.Flow in Atomizers 6.Atomizer Performance 7.External Spray Charcteristics 8.Drop Evaporation 9.Drop Sizing Methods Index

Atomization and Sprays

From water sprinklers to combustion devices of launch vehicles, the applications of the liquid injectors are innumerable. Owing to the usage of non-renewable sources, there is a global movement towards improvement in the existing combustion systems. Efficiency and fuel emissions are influenced by fuel spray characteristics. One of the techniques used to capture the information on spray characteristics is highspeed shadowgraphy. Estimation of the required parameters needs analysis of image series. An automated method to replace tiring manual calculations makes it the job of a few seconds. The basic tools of image processing are employed in this study to ease the computation.

Application of Digital Image Processing Method for Spray Characterization

Spray Burner Imaging and Characterisation Using Commercial Photographic Equipment

The effect of swirl flow on the spray characteristics (structure, droplet diameter and droplet velocity) is experimentally investigated for varying air-to-liquid momentum ratios in this work. The diagnostic techniques employed include high-speed shadowgraphy and 1D-PDPA. A commercial pressure swirl injector is mounted in a swirl stabilized model gas turbine burner to investigate the spray characteristics with and without the presence of swirling flowfield under isothermal conditions. In the absence of the injector flow the burner produced a converging-diverging flowfield at the burner exit, influenced by the bluffbody effect near to the exit and the swirling intensity farther downstream. The investigations reveal an unmistakable influence of the swirling flow on the droplet size, velocity and spatial distribution. Under the investigated momentum flux ratios the conical spray structure is altered and the droplets size and velocity at each location changed with the spatial variation in the magnitude and nature of the swirling flowfield. In general fine droplets are produced near to the high velocity air inflow, and coarser droplets in the recirculation zone owing to the longer residence time. The mean axial velocity of the droplet reduced in presence of swirling flow, with the droplets showing negative velocities at downstream locations.

https://jafmonline.net/JournalArchive/download?file_ID=51728&issue_ID=1006

R. Sadanandan

Papers

The Effect of Swirling Air-to-Liquid Momentum Ratio on the Spray and Droplet Characteristics