Design of an EGR Interface for Thermoplastic Intake Manifolds

The adaptation of EGR to recently introduced thermoplastic glass reinforced nylon (GRN) air intake manifolds requires precautions to protect the manifold from the effects of high gas temperatures. A thermal isolator is necessary to act as an interface between the high temperature EGR outlet tube and the thermoplastic manifold.

EGR tube isolator concepts were investigated through a combination of finite element heat transfer analysis and laboratory tests. Initial FEA models were correlated to lab tests. The resulting information was utilized to identify desirable shapes for the EGR thermal isolator for the available space and attachment mechanisms.