Plural layer fiber filter element and system for cleaning

A filter element and a system for cleaning said filter element, comprising:

• a plurality of layers each containing a number of tensioned fibers having a known coefficient of friction therebetween and arranged in substantially uniform orientation over at least a portion of their active length, along which portion at least, each of said fibers is disposed in close proximity to its adjacent fibers;
• a body member with a surface of a given radius of curvature constituting a backing surface for said fibers;
• nozzle means having at least one outlet for applying a mixture of two fluids in the form of at least one pressurized fluid jet against the fibers;
• and
• means for applying relative movement between said fiber layers and said fluid jet,
• wherein the overall thickness h of the fiber layers is determined by the expression:
• ##EQU2## wherein:
• P is the fluid pressure of the jet in dynes per cm.sup.2 ;
• A is the width of the nozzle's outlet in the direction of the fibers, in cm;
• B is the width of the nozzle's outlet in the direction across the fibers, in cm:
• .delta.1is the specific weight of a first fluid in the fluid jet, in gram mass/cm.sup.3 ;
• 67 2 is the specific weight of a second, heavier fluid, which is mixed with the first fluid, in gram mass/cm.sup.3 ;
• n is the number of fibers in a cross-section of one cm.sup.2 of the fiber layers;
• T is the tensional load on a single fiber in dynes;
• .mu. is the coefficient of friction between the fibers;
• and
• R is the radius of curvature of the fiber layers which is closest to the radius of curvature of the body member, in cm.