What is EHD film?
The momentary lifting force by the fluid, while the surfaces are normally approaching, is called a hydrodynamic squeeze film. The hydrodynamic squeeze film is a useful concept to remem- ber in connection with the mechanism of EHD lubrication.
What are types of lubrication?
There are three different types of lubrication: boundary, mixed and full film. Each type is different, but they all rely on a lubricant and the additives within the oils to protect against wear.
Where is hydrodynamic lubrication used?
Hydrodynamic lubrication is a term that defines a situation in which two rubbing surfaces are separated by a thin film of a lubricant. This situation is often beneficial and lubrication is used to reduce friction and/or wear of rubbing solids with the aid of liquid (or semi-solid) lubricant.
What is Electrohydrodynamic lubrication?
Definition. Elastohydrodynamic lubrication (EHL) is a mode of fluid-film lubrication in which hydrodynamic action is significantly enhanced by surface elastic deformation and lubricant viscosity increases due to high pressure.
What is boundary lubrication?
Boundary lubrication is defined as that in which the sliding surfaces are separated by a very thin molecular film of lubricant, so that the chemical and physical natures of the surfaces and the lubricant are of major importance.
What is minimum film thickness?
1 INTRODUCTION. The nominal minimum film thickness in dynamically loaded journal bearings, such as engine bearings, is of the same order of magnitude as the surface roughness and it often becomes such thin that the surface roughness asperities interfere, resulting in bearing operating in the mixed lubrication.
What are lubricants give examples?
A lubricant is a substance which introduced to reduce friction between surfaces in mutual contact, which ultimately reduces the heat generated when the surfaces move. For example – motor oil, friction modifier, friction additive, gel, silicons, flourocarbons, ect. Hope it helps you…
What are the examples of liquid lubricant?
Based on their origin, we classify as vegetable oil (i.e. castor and rapeseed); animal oil (fish oil); olive oil, mineral oil (the most popular and most economic category of liquid lubricant); finally, comes the synthetic lubricant.