1. Department of Mechanical Engineering, 20 Symonds St., University of Auckland, Auckland, New Zealand
2. Mechanical and Aerospace Engineering Department, University of California, Los Angeles 1597, USA
3. School of Engineering, RMIT University, GPO Box 2476, Melbourne, VIC 3001, Australia
4. Department of Chemical and Materials Engineering, 20 Symonds St., University of Auckland, Auckland, New Zealand