Liquid Jet Motion

Studies on the influence of the liquid jet motion on the cleaning efficiency

Workgroup: Hygienic production

Scientific Partners and Guidance:
Fraunhofer IVV Dresden, Mr. H. Stoye

Financing: IVLV
Duration: 2013

The law requires machine manufacturers and plant operators in the IPPC Directive on the prevention and reduction of environmental impact through the use of best available technology. Because of the balancing act between consumer safety and environmental responsibilities, a continuous optimization of cleaning processes is necessary. The focus of this research project is the cleaning of tanks in the food industry with rotating jet cleaners. The cleaning is carried out mainly by the mechanical force of the liquid jet on the soil layer.

The function-related track pattern (Fig. 1) is pressure and flow rate dependent and generally independent of the design and the manufacturer of the rotating jet cleaner. The moving liquid jet cleans an area around the impinging jet (Fig. 2), which is represented in the soil as cleaned track. With each rotation the pattern of cleaned tracks becomes denser, until the entire inner surface is cleaned. The track width is dependent on the jet diameter, the pressure, the relative jet moving speed, the substrate and the soil itself. By reducing the overlap of the track to a minimum, but same reliable cleaning, the total length of the jet pattern can be reduced and thus the efficiency increased. By investigation with a food soil on flat test geometry the following results can be expect:

  1. Quantitative analysis of the conventional net-shaped track pattern
  2. Identification of the ideal distance between flanking liquid jet paths to avoid unnecessary overlap of the cleaned tracks
  3. Influence of preweakening the swellable soil layers on the width of the cleaned tracks

After the successful research project a methodical approach enables the investigation of influence of relative jet moving speed in terms of their cleaning effect. This method contributes rapid optimization of existing products for manufacturers of cleaning components by determination of new process-related parameters. The end user receives a way to ensure the safety of the consumer and at the same time to realize a more resource-efficient production.