초록 ▼

A combined EGR cooler and non-thermal plasma device has first and second fluid passageways which are in heat exchange communication with one another. One or more electrodes are located in the second fluid passageway. The electrodes are connected to a voltage source. When a voltage of sufficient mag

A combined EGR cooler and non-thermal plasma device has first and second fluid passageways which are in heat exchange communication with one another. One or more electrodes are located in the second fluid passageway. The electrodes are connected to a voltage source. When a voltage of sufficient magnitude is applied to the electrodes, a non-thermal plasma is generated in the second fluid passageway. The device can be constructed in the form of a shell-and-tube heat exchanger or a stacked-tube type heat exchanger, wherein the electrodes extend through the heat exchange tubes. Hot exhaust gases preferably flow through the tubes in heat exchange contact with a liquid coolant, thereby cooling the exhaust gases. The electrodes generate non-thermal plasma inside the tubes, converting at least a portion of the NO in the exhaust to NO2, which reacts with soot in the exhaust gases to generate CO2 and N2, thereby cleaning the exhaust gases.

대표청구항 ▼

What is claimed is: 1. A heat exchanger, comprising: a first fluid passageway extending between a first inlet port and a first outlet port; a second fluid passageway extending between a second inlet port and a second outlet port, wherein the first and second fluid passageways are sealed from one an

What is claimed is: 1. A heat exchanger, comprising: a first fluid passageway extending between a first inlet port and a first outlet port; a second fluid passageway extending between a second inlet port and a second outlet port, wherein the first and second fluid passageways are sealed from one another; at least one heat exchange surface through which the first and second fluid passageways are in heat exchange communication with one another; and at least one electrode located in said second fluid passageway; wherein the at least one electrode is connected to a voltage source which, during use of the heat exchanger, applies a voltage to said at least one electrode; and wherein the voltage is of sufficient magnitude to cause the at least one electrode to generate a non-thermal plasma in the second fluid passageway; wherein the heat exchanger comprises a shell and tube heat exchanger comprising a plurality of parallel, elongate, longitudinally-extending tubes having hollow interiors, the tubes arranged in a tube bundle received within a longitudinally-extending housing; wherein the first fluid passageway comprises an interior of the housing and the second fluid passageway comprises the hollow interiors of the tubes; wherein said at least one least one heat exchange surface comprises side walls of the tubes; wherein each of said tubes has one of said electrodes extending longitudinally through its hollow interior in spaced relation to the tube side wall; and wherein opposite ends of said electrodes are supported by support structures located at opposite ends of the housing; said support structures preventing electrical contact between the electrode and the tube bundle and housing; one of said support structures incorporating an electrically conductive structure through which the voltage is applied to one end of each electrode. 2. The heat exchanger of claim 1, wherein the first and second inlet ports and the first and second outlet ports are formed in the housing. 3. The heat exchanger according to claim 1, wherein sealing means are provided adjacent to the ends of the tubes to prevent flow communication between the first and second fluid passageways. 4. The heat exchanger of claim 3, wherein the sealing means comprises a pair of headers located at opposite ends of the tubes; wherein the ends of the tubes are sealed to the headers and the headers are provided with a plurality of perforations, each of which communicates with an interior of one of the tubes. 5. The heat exchanger of claim 4, wherein the second fluid passageway further comprises an inlet manifold through which the second fluid inlet port communicates with the interiors of the tubes and an outlet manifold through which the second fluid outlet port communicates with the interiors of the tubes. 6. The heat exchanger of claim 1, wherein the at least one electrode is supported by one or more electrically insulating support structures. 7. The heat exchanger of claim 6, wherein the second fluid passageway is elongate and has opposite ends which are open; wherein each of the electrodes extends completely through the second fluid passageway; and wherein opposite ends of the electrodes are located outside the second fluid passageway and are supported by said support structures. 8. The heat exchanger of claim 7, wherein the housing has opposite ends to which the support structures are attached. 9. The heat exchanger of claim 8, wherein the support structures comprise end caps which seal the ends of the housing. 10. The heat exchanger of claim 7, further comprising an electrically conductive plate which is in electrical contact with one end of each of the electrodes and through which the voltage is applied to the electrodes, wherein the electrically conductive plate is attached to one of the support structures. 11. The heat exchanger of claim 6, wherein said support structures are located between opposite ends of the electrodes and maintain spacing between the electrodes and the at least one heat exchange surface. 12. The heat exchanger of claim 1, wherein the voltage is from about 1 to 30 kV. 13. The heat exchanger of claim 1, wherein the voltage is pulsed. 14. A heat exchanger, comprising: a first fluid passageway extending between a first inlet port and a first outlet port; a second fluid passageway extending between a second inlet port and a second outlet port, wherein the first and second fluid passageways are sealed from one another; at least one heat exchange surface through which the first and second fluid passageways are in heat exchange communication with one another; and at least one electrode located in said second fluid passageway; wherein the at least one electrode is connected to a voltage source which, during use of the heat exchanger, applies a voltage to said at least one electrode; and wherein the voltage is of sufficient magnitude to cause the at least one electrode to generate a non-thermal plasma in the second fluid passageway; wherein the heat exchanger comprises a tube stack heat exchanger comprising a plurality of parallel, elongate, longitudinally-extending tubes having hollow interiors, each of the tubes having a width which is substantially greater than its height, the tubes arranged in a tube stack received within a longitudinally-extending housing; wherein the first fluid passageway comprises a plurality of spaces between the tubes and the second fluid passageway comprises the hollow interiors of the tubes; wherein said at least one heat exchange surface comprises side walls of the tubes; wherein each of said tubes has at least one of said longitudinally-extending electrodes extending through its hollow interior, wherein said at least one electrode is arranged in spaced relation to the tube side wall; and wherein opposite ends of said at least one electrode are supported by support structures located at opposite ends of the housing; said support structures preventing electrical contact between said at least one electrode and the tube stack and housing; one of said support structures incorporating an electrically conductive structure through which the voltage is applied to one end of each electrode. 15. The heat exchanger of claim 14, wherein each of said tubes has a plurality of said longitudinally-extending electrodes extending through its hollow interior and being in spaced parallel relation to one another across the width of the tube. 16. The heat exchanger of claim 14, wherein the first and second inlet ports and the first second outlets ports are formed in the housing. 17. The heat exchanger according to claim 14, wherein sealing means are provided adjacent to the ends of the tubes to prevent flow communication between the first and second fluid passageways. 18. The heat exchanger of claim 17, wherein the sealing means comprises a pair of headers located at opposite ends of the tubes; wherein the ends of the tubes are sealed to the headers and the headers are provided with a plurality of perforations, each of which communicates with an interior of one the tubes. 19. The heat exchanger of claim 18, wherein the second fluid passageway further comprises an inlet manifold through which the second fluid inlet port communicates with the interiors of the tubes and an outlet manifold through which the second fluid outlet port communicates with the interiors of the tubes. 20. The heat exchanger of claim 14, wherein the at least one electrode is supported by one or more electrically insulating support structures. 21. The heat exchanger of claim 20, wherein the second fluid passageway is elongate and has opposite ends which are open; wherein each of the electrodes extends completely through the second fluid passageway; and wherein opposite ends of the electrodes are located outside the second fluid passageway and are supported by said support structures. 22. The heat exchanger of claim 21, wherein the housing has opposite ends to which the support structures are attached. 23. The heat exchanger of claim 22, wherein the support structures comprises end caps which seal the ends of the housing. 24. The heat exchanger of claim 21, further comprising an electrically conductive plate which is in electrical contact with one end of each of the electrodes and through which the voltage is applied to the electrodes, wherein the electrically conductive plate is attached to one of the support structures. 25. The heat exchanger of claim 20, wherein said support structures are located between opposite ends of the electrodes and maintain spacing between the electrodes and the at least one heat exchange surface. 26. The heat exchanger of claim 14, wherein the voltage is from about 1 to 30 kV. 27. The heat exchanger of claim 14, wherein the voltage is pulsed.