Patent ID: 8276653

Claim:
A heat exchanger for transfer of heat between a second fluid flowing at a high velocity and a first fluid, comprising: a. a housing defining an interior space, b. a plurality of heat exchange tubes spaced apart from each other, fixed in said housing, and extending in a first direction within said interior space, c. first inlet for receiving said first fluid into and through said tubes, and first outlet for discharging said first fluid out of said tubes, d. second inlet for receiving said second fluid into said interior space in an inlet flow direction transverse of said first direction, whereby outer surfaces of said heat exchange tubes in said interior space are contacted by said second fluid flow, and second outlet for discharging said second fluid out of said interior space, and e. an impingement plate assembly situated in said interior space of said housing between said second inlet and said plurality of tubes and comprising: (i) a top plate facing said second inlet and mounted in said housing, said top plate having an unperforated top surface that lies in a plane transverse to said inlet flow direction and onto which said second fluid flow impinges, said top plate thus positioned to block said second fluid flow from direct high velocity impingement on said heat exchange tubes, and (ii) a bottom plate fixed to, spaced apart from and generally parallel to said top plate, wherein said top plate is overlying said bottom plate, said bottom plate defining therethrough an aperture extending from top to bottom thereof, whereby said fluid flow exiting said aperture in said bottom plate moves in a flow path about said heat exchange tubes that reduces stagnation of said fluid about said tubes and reduces corrosion of said tubes' outer surfaces, (iii) said impingement plate assembly further comprising spacer elements maintaining said bottom plate said spaced apart from said top plate, with a central axis extending in the top to bottom direction through said top and bottom plates, said spacer elements being spaced apart about said central axis and fixed to said top and bottom plates, whereby said plates define between them a flow path for part of said second fluid after it impinges on said top plate to flow between said top and bottom plates and thence downward through said aperture in said bottom plate.