Radially resolved measurement of stator heat transfer in a rotor–stator disc system

✍ Scribed by D.A. Howey; A.S. Holmes; K.R. Pullen

• Publisher: Elsevier Science
• Year: 2010
• Tongue: English
• Weight: 968 KB
• Volume: 53
• Category: Article
• ISSN: 0017-9310
• DOI: 10.1016/j.ijheatmasstransfer.2009.09.006

✦ Synopsis

This paper describes a new experimental method for measuring stator heat transfer in a rotor-stator disc system using an electrical heater array. The system is partially blocked at the periphery, with radial outflow of rotor-pumped air from an inlet at stator centre. The aim is to improve thermal performance prediction for air-cooled disc type electrical machines. Local Nusselt numbers were measured for 0:6 < r=R < 1 at three non-dimensional gap ratios G ¼ g=R ¼ ð0:0106; 0:0212; 0:0297Þ and rotational Reynolds numbers 3:7e4 6 Re h 6 5:6e5. Transition at the stator is observed to occur at Re h > 3e5 for all gap ratios. Increased Nusselt numbers at the periphery are observed for all Re h and G because of the ingress of ambient air along the stator due to the rotor pumping effect.