Patent ID: 8393314
Filing Date: 2013-03-12
Classification: F01P,F02B,F02M,Y02T

Abstract:
1. A method of cooling combustion-created exhaust gas being recirculated in an internal combustion engine from an exhaust system that conveys exhaust gas created by combustion of fuel in engine cylinders to an intake system through which air for supporting the combustion of fuel is delivered to the engine cylinders, thereby entraining the recirculated exhaust gas in the air, the engine having engine structure that contains both the engine cylinders and coolant passageways through which liquid coolant circulates to cool the engine structure, the method comprising: flowing exhaust gas which is being recirculated successively through a first heat exchanger and a second heat exchanger; circulating liquid coolant both in a first loop that comprises a) one of the first and second heat exchangers, b) a third heat exchanger, and c) at least some of the coolant passageways in the engine structure, and in a second loop that comprises d) the other of the first and second heat exchangers, e) first and second branches in parallel flow relation with each other, the first branch comprising a fourth heat exchanger, and f) at least some of the coolant passageways in the engine structure, and controlling how much of the coolant circulating in the second loop is apportioned to the first branch and to the second branch.