STEAM BEARING STUDIES. PART II. THERMAL ENVIRONMENTAL ANALYSIS OF AN EXTERNALLY PRESSURIZED STEAM BEARING.
Abstract
The presence of condensate in a steam lubrication film has been identified as a prerequisite for 'Steam Hammer' instability in externally-pressurized steam-lubricated journal bearings. This analysis identifies the source or sources of condensate in the bearing film and effects the bearing configuration and operating conditions have on the inception the inception of condensation within the bearing film and in the region of the bearing feed holes. It is shown that jacketing the vapor lubrication film with a manifold of condensing supply steam can maintain the bearing and shaft surfaces of the vapor lubrication film superheated with respect to the local saturation conditions of the film. The thermal analysis also shows that for a wide range of operating conditions a dual manifold arrangement results in essentially isothermal vapor film conditions. This latter result significantly simplifies the analysis of vapor lubricated externally pressurized bearings, since the energy equation for the film is therefore only weakly coupled to the lubrication equation. Although no attempt has been made, as yet, to generate thermal design charts for steam journal bearings, the general agreement between experimental measurements and this analysis along with the flexibility of the thermal model encourage an effort along these lines. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 01, 1967
- Accession Number
- AD0665283
Entities
People
- D. E. Dougherty
- F. C. Hsing