Construct a Nafion based Goldberg Rotator for aerosol humidity studies

Study level

Master of Philosophy


Vacation research experience scheme

Topic status

We're looking for students to study this topic.


Dr Graham Johnson
Senior Lecturer
Division / Faculty
Science and Engineering Faculty


Ultimately this system will be used to study the effect of changing relative humidity on the survival of airborne pathogens including bacteria and viruses.

Research activities

The objective is to design and oversee the building of a rotating drum constructed from a water permeable membrane attached to a drum shaped cage. The drum rotation rate can be chosen to combat gravitational settling for a specific particles size and thereby maintain aerosol suspension for very long periods of time.

The rotating Nafion drum will be suspended inside a humidity controlled enclosure in order that the relative humidity within the drum itself responds to changes in the relative humidity of the surrounding enclosure.

You will need to optimize the design by modelling the diffusion of water vapour into and throughout the drum, optimizing the drum dimensions for maximum volume and speed of equilibration after changes in the surrounding humidity.


Minimum outcome: a practical design with predicted equilibration response to a step change in surrounding relative humidity, identified membrane materials, optimal rotation rates, cost estimate.


Contact the supervisor for more information.