1. Department of Biomedical Engineering and Mechanics, Laboratory for Turbomachinery and Components, Virginia Tech, Norris Hall, Room 107, 495 Old Turner Street, Blacksburg, VA 24061 e-mail:
2. Department of Biomedical Engineering and Mechanics, Laboratory for Turbomachinery and Components, Virginia Tech, Norris Hall, Room 324, 495 Old Turner Street, Blacksburg, VA 24061 e-mail: