GB638282A - Improvements in recuperative heat exchangers of the rotary type for gaseous media - Google Patents

Abstract

638,282. Rotary plate heat-exchangers; regenerators heating air for combustion. AKTIEBOLAGET MOTALA VERKSTAD. Jan. 23, 1947, No. 2181. [Class 64(iii)] In a recuperative heat-exchanger in which two gases, e.g. air and flue gas, flow radially through adjacent or alternate unobstructed passages 4, 5 formed in a housing 8 by one or more smooth metal discs 3 fixed transversely on a rotatable shaft 1, the set of passages for each gas communicating with a separate chamber 11 or 15 around the shaft 1 and with a separate outer chamber 31 or 32, the two gases are in contra-flow between the inner and outer chambers. The space between the inner edges of the discs and the hub 2 is divided by walls 25, see Fig. 5, into four channels 26a, 26b, 27a, 27b along the axis, of which two 26a, 26b communicate with passages 4 and the others with passages 5. On the curved surface of the rotor a number of openings are arranged in rows parallel to the axis, the rows of openings 23 corresponding to alternate passages 4 for air flow being screened by channels 22 and offset from the rows of openings 35 corresponding to the intervening passages 5 for the flue gases. The channels extend along the rotor parallel to the axis and project to act as fan blades for the flue gases which pass from the openings 35 (see Fig. 5) and the bottom half of Fig. 7, into the spiral-shaped outlet chamber 32 formed around the rotor by the housing 8, having entered the passages 5 from channels 27a, 27b and an inlet 14. The air enters an axial inlet 10 in the end wall 9 of the housing 8 and passes through the inlet chamber 11, radial passages 17 (see Fig. 3) between the end disc 6 and an outer wall 19 of the rotor, to the channels 22. From the channels it passes through flow passages 4 towards the axis and channels 26a, 26b from whence it is drawn, by fan blades 29 attached between a large end disc 3a and an end wall of the rotor, into the outlet chamber 31. A stationary partition 30 with a labyrinth packing device separates the outlet chambers 31, 32 which have tangential outlets (not shown). A modification, without a fan wheel, is described in which radial channels are formed at one end of the housing, the air entering the apparatus by the alternate radial channels and leaving it by the intervening radial channels at the same end of the housing. The air is throttled, to control its velocity, as it leaves the channels extending along the curved surface of the rotor to enter the flow passages between the discs. The four walls forming the hub channels are curved to form fan blades. Specification 587,149 is referred to.