Patent ID: 7287522

Claim:
An engine system comprising: an engine; an exhaust system coupled with said engine; a heat exchanger coupled with said exhaust system and including a heat conducting carbon foam, said heat exchanger having an exhaust gas passage and a second passage, said exhaust gas passage and said second passage being configured to exchange heat between fluids therein at least in part via said foam; wherein said engine comprises an internal combustion engine; said heat exchanger comprises a gas to gas heat exchanger, said second passage comprising a cooling air passage fluidly separate from said exhaust gas passage and having an air inlet and an air outlet; said heat conducting carbon foam comprises a carbon foam block disposed within at least one of said exhaust gas passage and said cooling air passage; wherein said engine comprises a compression ignition engine, said exhaust system comprising an exhaust gas recirculation loop having said heat exchanger coupled therewith; and wherein said heat exchanger comprises a housing including a plurality of exhaust gas portions each having an exhaust gas passage disposed therein, and a plurality of cooling air portions each having a cooling air passage disposed therein, said housing portions being in an alternating stacked arrangement.