Thermoelastic instability in a seal-like configuration

Abstract For the geometry of two flat plates contacting on a straight common edge with sliding parallel to the line of contact, conditions are found where pressure perturbations on the interface will grow, diminish or remain unchanged. The effects of materials properties, friction coefficient, and sliding speed are delineated. Conditions which lead to a growing disturbance may be thought of as undesirable in that they lead to locally increased contact loading as well as locally increased temperatures. Adjacent to the regions of increased pressure are regions of reduced pressure where the surfaces may part, and give rise to leakage when the line of contact is considered to represent the lip of a seal. It is shown that materials sliding on their own kind tend to be stable relative to this phenomenon, while good thermal conductors sliding on good thermal insulators must always have some characteristic sliding speed above which instability will occur.