Air heater seals

A axial seal arrangement for an air heater, comprising:

• an air heater housing having substantially a cylindrical shape and an inner circumferential surface;
• an air heater rotor contained within said housing, said rotor having substantially a cylindrical shape with an outer circumferential surface, said rotor rotating about a center axis;
• said inner and said outer circumferential surfaces defining a gap therebetween;
• said gap varying in size due to differential expansion within said rotor and said housing;
• at least one flexible sealing element having an elongated shape and an axis;
• at least one torsional element having an elongated shape, said at least one torsional element having an axis and a peripheral surface, said at least one torsional element further having a first end and a second end;
• each of said at least one sealing element being fixedly attached to said peripheral surface, along a length of a corresponding said at least one torsional element in a manner so that said axis of said at least one sealing element is parallel to a corresponding said axis of said at least one torsional element;
• said first end of each of said at least one torsional elements being fixedly attached to one of said outer circumferential surface and said inner circumferential surface, each of said at least one torsional element extending along the same parallel to said center axis;
• said second end of said at least one torsional element being free to rotate about said axis of said at least one torsional element;
• said at least one sealing element projecting across at least a portion of said gap so as to substantially obstruct fluid flow therebetween;
• and
• said at least one torsional element having a preselected torsional rigidity so as to allow said at least one sealing element to adequately rotate about said axis of said at least one torsional element in response to a force due to a varying size of said gap.