1. Research Professor, Civil Engineering Division, Univ. of Dundee, Dundee DD1 4HN, U.K. (corresponding author).
2. Former Research Fellow, Civil Engineering Division, Univ. of Dundee, Dundee DD1 4HN, U.K.
3. Chair in Thermofluids, Dept. of Mechanical Engineering, Univ. of Sheffield, Sheffield S10 2TN, U.K.
4. Former Research Fellow, Thermo-Fluid Mechanics Research Centre, Univ. of Sussex, Brighton BN1 2QT, U.K.
5. Research Student, Dept. of Mechanical Engineering, Univ. of Sheffield, Sheffield S10 2TN, U.K.