Apparatus for frictionally heating liquid

Apparatus for heating liquid comprising:

• a rotor for disposition within a housing defining a reservoir for a heat transfer liquid, said rotor being rotatable about an axis of rotation in a predetermined direction and having axially spaced front and rear annular face members each having radially spaced inner and outer edges, radially spaced inner and outer cylindrical surfaces of predetermined axial width joining the respective inner and outer edges of said face members, a web having an axial width substantially less than the axial width of said inner cylindrical surface and being fixed to said surface midway of the width thereof, said web with said inner cylindrical surface on either side of said web defining first and second annular inlet cavities in said rotor, and a plurality of passages in said rotor having outlets circumferentially spaced around and opening through said outer cylindrical surface, alternate ones of said passages having inlets opening through said inner cylindrical surface on one side of said web to connect said alternate ones of said outlets with said first inlet cavity, the other alternate ones of said passages having inlets opening through said inner cylindrical surface on the other side of said web to connect said other alternate outlets with said second inlet cavity.