Exhaust gas heat exchanger
AssigneeHoneywell International Inc.
InventorsMatthew Thomas Graham Stonehouse, Stewart William Leedham
Life of this patent
Estimating the term…
Abstract
An exhaust gas heat exchanger comprising an external shell (20) extending between two tube plates (30, 31) and defining a coolant chamber; internal tubes (38) forming exhaust gas passages which extend between the tube plates (30, 31); an exhaust gas manifold divided by a baffle plate (29) into first and second chambers (26, 28) with an exhaust gas inlet (25) and outlet (27) respectively. The baffle plate (29) is provided with a valve (51) which can be operated between an open position, in which exhaust gas flows along the cooling tubes (38), and a closed position, in which exhaust gas is diverted directly from the first chamber (26) to the second chamber (28).
Claims10
An exhaust gas heat exchanger of the shell and tube type, said heat exchanger comprising a shell having a hollow interior between opposite ends, an exhaust gas manifold secured to one end of the shell, and thermally conductive tube means extending through the interior of the shell from said one end of the shell, the exhaust gas manifold comprising first and second exhaust gas chambers which are mutually adjacent, each of said exhaust gas chambers comprising a respective exhaust gas inlet and an exhaust gas outlet, said tube means providing an exhaust gas flow path between the exhaust gas outlet of said first exhaust gas chamber and the exhaust gas inlet of said second exhaust gas chamber, said heat exchanger being characterised by valve means providing a gas flow path directly between said first and second exhaust gas chambers when said valve means is open, said valve means substantially closing a direct gas flow path between said first and second exhaust gas chambers when said valve means is closed, whereby when a source of flowing exhaust gas is coupled to the exhaust gas inlet of said first exhaust gas chamber and said valve means is closed, exhaust gas is constrained to flow from the exhaust gas inlet of said first exhaust gas chamber to the adjacent exhaust gas outlet of said second exhaust gas chamber by way of said thermally conductive tube means to exchange heat with fluid in the interior of the shell and surrounding said tube means, whereas when said valve means is open, exhaust gas is allowed to flow from the exhaust gas inlet of said first exhaust gas chamber directly to the adjacent exhaust gas outlet of said second exhaust gas chamber and so bypass said tube means.
A heat exchanger as claimed in any preceding claim, characterised in that said first and second exhaust gas chambers are mutually contiguous on either side of a common internal wall of the manifold, said valve means being mounted in said common internal wall of the manifold.
A heat exchanger as claimed in any preceding claim, characterised in that when said valve means is open to allow exhaust gas to flow from the exhaust gas inlet of said first exhaust gas chamber directly to the exhaust gas outlet of said second exhaust gas chamber, the valve means simultaneously closes one of the exhaust gas outlet of said first exhaust gas chamber and the exhaust gas inlet of said second exhaust gas chamber.
Dependencies are inferred from the claim text.