Summer School: Modelling of Atomisation and Sprays for Technical and Industrial Applications

21st - 24th July 2008

Place: Halle (Saale), Germany.

Organiser: Prof. Martin Sommerfeld

Aims

The atomisation of liquids into small droplets and the resulting spray evolution is of great importance for a number of technical and industrial processes, as for example: spray combustion, spray coating, spray cooling, spray agglomeration, spray compaction and so on. Essential for producing a desired spray droplet size distribution is the atomisation of the liquid using different types of nozzles. The spray evolution is mainly governed by the nozzle geometry (initial condition) and aerodynamic transport.For analysing, optimising and designing spray processes increasingly numerical computations (CFD) are being used, also by industry. Industrial relevant processes are generally calculated based on the Reynolds averaged conservation equations in connection with an appropriate turbulence model. For calculating two-phase flows extended approaches have to be used. The most known methods are the twofluid (or Euler/Euler) approach and the Euler/Lagrange method. In the two-fluid approach to interpenetrating and interacting continua are considered resulting in two sets of conservation equations with similar structure, supplemented by the interaction terms. Multiple sets of conservation equations have to be used for resolving a spectrum of droplet sizes which is especially important for spray predictions.

The Euler/Lagrange method simulates the dispersed phase by tracking a large number of computational droplets. This approach is very attractive for predicting spray dispersion, however needs as an input the initial droplet size distribution. Both methods need to be extended appropriately for modelling all relevant elementary processes, such as liquid sheet or jet break-up, droplet interaction and collisions, droplet break-up and heat at mass transfer.

During the 4-day summerschool recent advances on the modelling and numerical prediction of sprays will be introduced. The areas to be covered in the summerschool are:

• Modelling of atomisation by different approaches
• Modelling of droplet break-up and collisions
• Modelling of droplet evaporation and combustion
• Numerical prediction and validation for spray processes
• Applications, such as sprays in engines, spray drying, spray cooling, spray coating

Additionally, lectures on recent advancements on single pointspray measurements and imaging methods for spray analysis willbe given.

spray-summerschool_2008.pdf