Projects undertaken by Prof Castle have involved many of significant importance to industry including: manufacturing (electrostatic painting), the environment (air and water pollution control), agriculture (electrostatic crop spraying), copying and printing (electrophotography), recycling (plastics separation) and electrostatic coating (coated abrasives).

Currently active projects include:

  1. Numerical modeling of the Trichel pulses in negative corona
  2. 3-D simulation of the mechanical and electrical effects in the electrostatic painting process
  3. Electrohydrodynamic flow fields in electrostatic precipitators
  4. Electric field interactions in thin dielectric films
  5. Electric field enhancement of heat transfer using corona
  6. The size dependency of the charge to mass ratio in liquid paints and powder coating