Egr system having flow restricting valve

A method for regulating a fluid flow, comprising:

• directing a flow of fluid through an inlet of a valve;
• directing the flow of fluid through an outlet of the valve;
• and
• selectively redirecting a varying amount of the flow of fluid from the inlet back toward the inlet to vary a restriction on the flow of fluid from the inlet to the outlet.

An exhaust system for an engine, comprising:

• an intake manifold configured to direct air into the engine;
• an exhaust manifold configured to receive exhaust away from the engine;
• a turbocharger having a turbine fluidly connected to the exhaust manifold and a compressor fluidly connected to the intake manifold;
• an EGR passage in communication with the exhaust manifold and the intake manifold;
• and
• a valve disposed in the EGR passage and having:
• a body;
• an inlet formed within the body and having a spherical first end surface with a raised convex first opening;
• an outlet formed within the body, opposite the inlet, and having a second end surface with a second opening, wherein the second end surface is generally flat and perpendicular to the first end surface;
• and
• a restriction formed between the first end surface and the second end surface and connecting the first and second openings,
• wherein:
• the inlet of the valve has a diameter of about 150 mm that tapers outward toward the restriction;
• the outlet of the valve has a diameter of about 180 mm that remains generally constant along its length;
• and
• the first end surface of the fixed fluid valve has a radius of curvature of about 30-50 mm.