Rotary heat exchanger

Abstract

A rotary heat exchanger through which a first fluid flowan outside air or inlet air flow, for exampleand a second fluid flowan exit air or outgoing air flow, for examplecan flow in a counterflow configuration, has a rotatably mounted rotor (5) that has a first flow sector for the first fluid flow and a second flow sector for the second fluid flow through which the rotor (5) passes during a rotation, a frame in which the rotor (5) is rotatably supported, and a sealing assembly (9) by means of which an inflow side of the first fluid flow and an outflow side of the second fluid flow can be separated from the outflow side of the first fluid flow and from an inflow side of the second fluid flow, respectively. In order to simplify the sealing assembly, with the aim being that a reliable seal between the inflow and outflow sides of the two fluid flows be automatically ensured during operation of the rotary heat exchanger, it is proposed that the sealing assembly (9) have a first seal (12) that bears sealingly against the side of a partition (10) directed upstream into the first fluid flow (2), and a second seal (13) that bears sealingly against the side of the same partition (10) directed upstream into the second fluid flow (3).

Claims

1. A rotary heat exchanger through which a first fluid stream and a second fluid stream can flow along an axis in a counterflow configuration, the heat exchanger comprising: a frame; a partition in the frame having axially opposite end faces and formed on the axis with a circular cutout through which the streams flow axially oppositely; a rotor that extends axially through the cutout, that is rotatable about an axis in the frame, that passes through a first flow sector for the first fluid stream and a second flow sector for the axially oppositely flowing second fluid stream during a rotation, and that has a radially outwardly directed cylindrical edge surface, an L-section and flexible annular first seal having a part that extends axially and is fixed to the edge surface of the rotor and a part that extends radially and that is of such flexibility as to be pressed axially sealingly by the first fluid stream against the face of the partition directed upstream into the first fluid stream; and an L-section and flexible annular second seal having a part that extends axially and is fixed to the edge surface of the rotor and a part that is of such flexibility as to be pressed axially sealingly by the second fluid stream against the opposite face of the partition directed upstream into the second fluid stream.

2. The rotary heat exchanger defined in claim 1, wherein the partition is axially spaced from two axial end faces of the rotor on the cylindrical outer edge surface of the rotor and the circular cutout has an inside diameter slightly greater than an outside diameter of the rotor at the outer cylindrical surface.

3. The rotary heat exchanger defined in claim 2, wherein the partition is centered equidistant between the two axial end faces of the rotor on the cylindrical outer edge surface of the rotor.

4. The rotary heat exchanger defined in claim 1, wherein the seals are made of an abrasion-resistant and flexible material that is impermeable to fluids, so that the axially extending parts of the seals can be fixed on the cylindrical outer edge surface of the rotor and the radially extending parts of the seals can be brought into sliding and sealing abutment against the respective side of the partition.

5. The rotary heat exchanger defined in claim 1, wherein the first seal and the second seal run annularly completely around the rotor on the cylindrical edge surface.

Description

BRIEF DESCRIPTION OF THE DRAWING

(1) The invention will be explained below in further detail on the basis of an embodiment with reference to the drawing.

(2) FIG. 1 is a perspective schematic view of an embodiment of a rotary heat exchanger according to the invention;

(3) FIG. 2 is a front view of the embodiment of the rotary heat exchanger according to the invention shown in FIG. 1; and

(4) FIG. 3 is a partial, perspective schematic view of a detail of the embodiment of the rotary heat exchanger according to the invention shown in FIGS. 1 and 2 that are essential for the invention.

SPECIFIC DESCRIPTION OF THE INVENTION

(5) Two fluid flows 2, 3 flow axially in opposite directions through a rotary heat exchanger 1 according to the invention, of which a perspective and a front view are shown in respective FIGS. 1 and 2. The first fluid stream 2 is an outside air or inlet air stream 2, and the second fluid stream 3 is an exhaust air or outgoing air stream 3. The two fluid flows 2 and 3 are illustrated in FIG. 1 by directional arrows.

(6) In the illustrated embodiment, the rotary heat exchanger 1 has a frame 4 with an approximately square outer periphery. This frame 4 surrounds the outer periphery of a rotor 5 of the rotary heat exchanger 1. The rotor 5 has a cylindrical outer lateral edge surface 6 that can for example be formed by a suitable sheet metal.

(7) Moreover, the heat exchanger 1 defines a first flow sector 7 through which the outside air or inlet air stream flows as shown in FIG. 1. The exchanger 1 also has a second flow sector 6 through which the exhaust or outgoing air stream 3 flows in an axial direction opposite the outside or inlet air stream 2.

(8) The rotor 5 of the rotary heat exchanger 1 is rotationally carried on an unillustrated bearing or hub.

(9) In the rotary heat exchanger 1, an inflow side of the outside air or inlet air stream 3 is sealed from the outflow side thereof. Similarly, the outflow side of the exhaust air or outgoing air stream 3 is tightly sealed from an inflow side thereof in the rotary heat exchanger 1. It should be pointed out that, in FIGS. 1 and 2, the rotary heat exchanger 1 is viewed from the inflow side of the outside air or inlet air stream 2 and an outflow side of the exhaust air or outgoing air stream 3.

(10) A sealing assembly 9 is in the frame 4 of the rotary heat exchanger 1 that separates the inflow and outflow sides of the outside air or inlet air stream 2 and of the exhaust air or outgoing air stream 3 from one another.

(11) It should be noted here that, as will readily be understood, a separating wall (not shown in the figures) is provided extending axially upstream and downstream from the rotary heat exchanger 1 for separating the outside air or inlet air stream 2 upstream and downstream from the rotary heat exchanger 1 from the exhaust air or outgoing air stream 3.

(12) The sealing assembly 9 that is provided in the frame 4 has a partition 10 whose outer periphery fits with the inner periphery of the frame 4 and is fastened there.

(13) The partition 10 is provided with a circular cutout 11 in its center region. The inner diameter of the circular cutout 11 of the partition 10 corresponds substantially to the outer diameter of the rotor 5 of the rotary heat exchanger 1 but is slightly larger, so that manufacturing tolerances occurring during the manufacture of the rotor 5 cannot possibly result in friction and the like and resulting damage.

(14) Nevertheless, in order to tightly separate the inflow and outflow sides from one another by means of the partition within the rotary heat exchanger 1, the sealing assembly 9 also has a first seal in the form of a first annular seal lip 12 and a second seal in the form of a second annular seal lip 13.

(15) In the illustrated embodiment of the rotary heat exchanger 1, the first annular seal lip 12 is on the inside diameter of the circular cutout 11 of the partition 10 on the inflow side of the outside air or inlet air stream 2 and analogously on the outflow side of the exhaust air or outgoing air stream 3. Similarly, the second annular seal lip 13 is on the inside diameter of the circular cutout 11 of the partition 10 on the outflow side of the outside air or inlet air stream 2 and the inflow side of the exhaust air or outgoing air stream 3, as can be seen particularly in FIG. 3, which will be explained in further detail below.

(16) In the illustrated embodiment, the two annular seal lips 12 and 13 extend around the entire periphery of the rotor 5 on its cylindrical outer edge surface 6.

(17) The partition 10 and the two annular seal lips 12 and 13 are axially spaced from the respective end faces of the rotor 5 against or from its cylindrical outer edge surface 6.

(18) The first annular seal lip 12 has an axially extending part 14 that extends axially of the rotor 5 and is seated on the cylindrical outer edge surface 6 of the rotor 5 and tightly fastened or mounted there. Moreover, the first annular seal lip has a radially extending sealing portion 15 that extends radially of the rotor 5 and engages the upstream axial face of the partition 10 that is on the inflow side of the outside or inlet air stream 2 and can be brought into sealing abutment against this face of the partition 10.

(19) Similarly as can be seen particularly from FIG. 3, the second annular seal lip 13 is on the outflow side of the outside air or inlet air stream 2 and thus the inflow side of the exhaust air or outgoing air stream 3 of the partition 10 and has an axially extending part 16 that is extends axially of the rotor 5, is seated on the cylindrical outer edge surface 6 of the rotor 5 and is tightly fastened or mounted there, and a radially extending part 17 that extends radially of the rotor 5, engages the upstream face of the exhaust air or outgoing air stream 3 of the partition 10 and can be brought into sealing abutment there against this face of the partition 10.

(20) The two annular seal lips 12 and 13 are made of a suitable abrasion-resistant and flexible material that is impermeable to fluids, such as an artificial leather material, an extruded plastic, or the like. Accordingly, the axially extending parts 14 and 16 of the two annular seal lips 12, 13 can be fixed securely on the cylindrical outer edge surface 6 of the rotor, and the radially extending parts 15 and 17 of the two annular seal lips 12, 13 can be simultaneously brought into sliding and sealing abutment against the face of the partition 10 with which they are associated.

(21) Since the seal between inflow and outflow sides is accomplished by only a single partition 10 in the case of the embodiment of the rotary heat exchanger 1 according to the invention described above, the pressure differentials on the annular seal lips 12 and 13 are relatively small and, furthermore, independent of the pressure differentials between the outside air or inlet air stream 2 on the one hand and the exhaust air or outgoing air stream 3 on the other hand. By virtue of the design of the sealing assembly 9 with a single partition 10, the pressure differential on the annular seal lips 12 and 13 is always equal to the pressure loss of the outside air or inlet air stream 2 and, accordingly, of the exhaust air or outgoing air stream 3, as it occurs on the rotor 5 forming the storage mass. Accordingly, in both flow sectors 7 and 8 of the rotor 5, a pressing of the radially extending part 15 of the first annular seal lip 12 against the side of the partition 10 facing toward the inflow side of the outside air or inlet air stream 2 and of the radially extending part 17 of the second annular seal lip 13 against the side of the partition 10 facing toward the inflow side of the exhaust air or outgoing air stream 3 is achieved, with the consequence that a reliable seal is achieved between the inflow and outflow sides both with respect to the outside air or inlet air stream 2 and the exhaust air or outgoing air stream 3.

(22) The manner in which the two seal lips 12 and 13 are fastened on the cylindrical outer edge surface 6 follows from the schematic view shown in FIG. 3 of a portion of the cylindrical outer edge surface 6 of the rotor 5, for which the partition 10 and the two annular seal lips 12 and 13 are also shown only partially. The gap in the two annular seal lips 12 and 13 in approximately the center of the figure is shown merely for purpose of illustration in order to clarify the arrangement or fitting-together of cylindrical outer edge surface 6, the two annular seal lips 12 and 13, and the partition 10.

(23) The partition 10 is seated between the two radial portions 15 and 17 of the two annular seal lips 12 and 13 and extends, like the two seal lips 12 and 13, around the entire periphery of the cylindrical outer edge surface 6 of the rotor 5.

(24) In an alternative embodiment of the rotary heat exchanger according to the invention, for the use of which both the installed position and the direction of the two fluid flows 2 and 3 are known, it is possible to mount the two seal lips on the partition 10. If the two seal lips do not move with the rotor, it is sufficient if corresponding seal lips are provided only on the inflow side in the two flow sectors, since greater pressure is always present on the inflow side than on the outflow side.

(25) As will readily be understood, unlike in the view in FIG. 3, the partition 10 can also be arranged approximately or exactly in the center of the rotor 5, seen axially.