Overview
Topic status: We're looking for students to study this topic.
Environmental aerosols typically carry finite electric charges of both signs. Many applications in research and particle measurement technology, such as the scanning mobility particle sizer (SMPS), require aerosols of known charge distributions. One method of reducing the charge on aerosol particles is neutralisation, where the aerosols are exposed to bipolar ions until they acquire an equilibrium charge. The resulting charge distribution is known as the Boltzmann Distribution and can be computed using mathematical equations. The SMPS uses a radioactive source (Kr-85) to ionise the aerosols entering the device. This generates equal numbers of positive and negative ions and imparts an equilibrium charge distribution to the aerosols before they enter the electrostatic classifier of the SMPS.
The aim of this project will be to replace the conventional radioactive source of the SMPS with an equivalent electrical device. Instead of using ionizing radiation, the aerosols will be neutralised with ions produced by corona discharge between two high voltage electrodes in a compact flow chamber. The project will involve constructing and testing the device under various conditions. You will compare the SMPS aerosol size distributions obtained when using the radioactive source and the electrical source and investigate the effects of parameters such as the applied voltage, electrode dimensions, air flow rate etc, and deduce the optimum conditions for use with an SMPS system.
- Study level
- Honours
- Supervisors
- QUT
- Organisational unit
Science and Engineering Faculty
- Research area
- Contact
- Please contact the supervisor.
Professor Lidia Morawska
Professor Zoran Ristovski
