GB620602A - Improvements in rotary heat-exchangers - Google Patents

Abstract

620,602. Regenerators &c. CORBITT, R. W., and POTTINGER, S. F. Aug. 22, 1946, No. 25147. [Class 64(i)] A rotary-drum heat exchanger includes a drum constructed in two concentric parts with poor thermal conductivity between them, the parts being maintained substantially at the temperatures of the adjacent stationary parts so that sealing between rotary and stationary parts is facilitated. The device comprises an outer casing 10 within which an inner casing 14 is mounted by flanges 14a engaging splines 17 on the outer casing, relative thermal expansion of the casings being thus possible. The flanges 14a are doubled and of such a shape that the outer flange is substantially at the temperature of the outer casing while the inner flange is at a higher temperature. The inner casing has axial openings 15, 16 at its ends and is divided into two spaces by a partition 18. The outer casing has radial openings 11, 12. Hot gas enters the opening 15, passes through apertures 19 in the inner casing, and leaves the outer casing through the opening 12, while the air to be heated enters at 11 and leaves the inner casing at 16. A rotatable drum structure surrounds the inner casing and comprises an inner drum 24 and an outer drum 23 secured to end rings 21, 22 and spaced apart radially so that they are thermally insulated from one another, the inner drum always being traversed by hot gas or heated air, and the outer drum by cooled gas or cold air. The sealing means between the rotary and stationary parts comprise piston rings 28, 29 and sealing strips 32, 33. On account of the twopart drum construction, the temperature differences at the seals are small and clearances may therefore be reduced. The drums contain rolls of wire gauze, (not shown), and rotate on rollers 25 mounted on the outer casing, one of the rings 21 being formed with rack teeth which are engaged by a pinion 27 to drive the drum assembly.