Internal combustion engine EGR system utilizing stationary regenerators in a piston pumped boost cooled arrangement

An EGR system for an internal combustion engine, said internal combustion engine including a block having a plurality of combustion chambers defined therein, an intake manifold in fluid communication with a source of combustion air and said combustion chambers, and a first exhaust manifold fluidly connected to at least one of said plurality of combustion chambers, said first exhaust manifold having a first primary exhaust outlet and a first EGR exhaust outlet, said EGR system comprising:

• a first check valve having an inlet and an outlet, said inlet being fluidly connected to said first EGR exhaust outlet of the first exhaust manifold;
• a regenerator directional flow control valve having an inlet port, first and second bidirectional flow ports, and a bleed air discharge port, said inlet port being in fluid communication with the outlet of said first check valve and said bleed air discharge port being in fluid communication with said first exhaust manifold;
• and
• first and second stationary regenerators, each of said first and second stationary regenerators having a first end and a second end, the first ends of the stationary regenerators being in fluid communication with a respective one of the first and second bidirectional flow ports of the regenerator directional flow control valve, and the second ends of the stationary regenerators being in selective communication with one of the intake manifold of the engine and said bleed flow line in fluid communication with said intake manifold.

A method for using an EGR system with an internal combustion engine wherein said engine includes a plurality of combustion chambers, an intake manifold in fluid communication with said combustion chambers, and a first exhaust manifold, and said EGR system includes a first check valve, a regenerator directional flow control valve, and first and second stationary regenerators, said method comprising the steps of:

• moving the regenerator directional flow control valve to a first position whereby exhaust gas received from the first check valve is directed to a first end of said first stationary regenerator, cooled during passage through said first stationary regenerator, and subsequently discharged from a second end of said first stationary regenerator to said fluid conduit in communication with said intake manifold, and simultaneously a flow of bleed air is directed from a conduit in fluid communication with said intake manifold to a second end of said second stationary regenerator thereby cooling said second stationary regenerator during passage of the bleed air therethrough, and then discharged from a first end of said secondary stationary regenerator and through the EGR directional flow control valve to said first exhaust manifold;
• and after a preselected time,
• subsequently moving said regenerator directional flow control valve to a second position whereby exhaust gas received from said first check valve is directed to the first end of said second stationary regenerator, cooled during passage through said secondary stationary regenerator, and then discharged from the second end of the second stationary regenerator to a conduit in fluid communication with the intake manifold of said engine and simultaneously a flow of bleed air is directed from said conduit in communication with said intake manifold to the second end of said first stationary regenerator, thence through the first stationary regenerator whereupon said first stationary regenerator is cooled during passage of the bleed air therethrough, and then discharged from the first end of said first stationary regenerator through the regenerator directional flow control valve to said first exhaust manifold.