Spray droplet sizing

Spray droplet sizing

Keywords Malvern,Spray deposition

The Malvern Instruments'Spraytec RTS 5000 Series comprises a range of laser diffraction-based analysis systems for the measurement of continuous sprays, domestic aerosols, metered dose inhalers and dry powder inhalers. The Spraytec Series has been designed to overcome common technical problems often experienced by users analysing liquid droplet sprays.

Malvern informs us that a range of optical benches allows the user to accommodate large volume spray plumes without the risk of contaminating system optics. A choice of optical systems allows the user to achieve the optimum balance between minimum measurable droplet size and working distance.Effective sealing prevents penetration of the optics and electronics by liquid sprays, and air purging can be provided to maximise protection.

Accurate analysis of pulsed or transient sprays is achieved using the Spraytec's Flash Mode software."Video" playback allows frame-by-frame inspection of droplet size distribution at rates up to 2,500Hz to show the development and consistency of spray plumes and is of particular relevance for spray samples of very brief duration.

Six triggering options provide optimum data collection capabilities for a wide variety of spray types,including short duration, random repetition or high repetition. In addition,analysis software is programmed to compensate for more complex spray samples such as highly concentrated sprays or those using propellants or volatile solvents. A further feature claimed of the software, a statistical process control utility, allows key spray parameters to be tracked over time on a simple graph.

The Spraytec Series employs a specially designed mounting scheme which combines flexibility with ease of use, ideal for applications requiring measurement at a location away from the laboratory. By keeping the computer and control unit separate from the optical system, even "hostile" samples, such as fuel sprays, can be analysed.

Details from Malvern Instruments Ltd, UK. Tel: +44 (0)1684 892456; Fax: +44 (0)1684 892789; E-mail: janr@malvern.co.uk