Exhaust gas recirculation mixer

A method of operating an exhaust gas recirculation mixer, the method comprising:

• directing a first fluid along an outer flow path to a throat of a mixing passage;
• directing a second fluid along an inner flow path to the throat of the mixing passage, wherein the inner flow path is nested within the outer flow path and is connected with the outer flow path via a mixing passage;
• wherein one of the first fluid or the second fluid comprises air;
• wherein the other of the first fluid or the second fluid comprises exhaust gas directed to the exhaust gas recirculation mixer from an engine;
• and
• wherein the exhaust gas and the air mix within the mixing passage to thereby provide a mixture to be directed to the engine;
• wherein the outer flow path and the inner flow path merge at a merge location;
• wherein the first fluid has a first velocity at the merge location;
• wherein the second fluid has a second velocity at the merge location;
• and
• wherein a ratio of the first velocity to the second velocity is in a range of 0.7 to 2.

A method of operating an exhaust gas recirculation mixer, the method comprising:

• directing a first fluid along an outer flow path to a throat of a mixing passage;
• directing a second fluid along an inner flow path to the throat of the mixing passage, wherein the inner flow path is nested within the outer flow path and is connected with the outer flow path via a mixing passage;
• wherein one of the first fluid or the second fluid comprises air;
• wherein the other of the first fluid or the second fluid comprises exhaust gas directed to the exhaust gas recirculation mixer from an engine;
• and
• wherein the exhaust gas and the air mix within the mixing passage to thereby provide a mixture to be directed to the engine;
• wherein the outer flow path and the inner flow path merge at a merge location;
• wherein the exhaust gas has an exhaust gas velocity at the merge location;
• wherein the air has an air velocity at the merge location;
• and
• wherein the method further comprises maintaining a ratio of the exhaust gas velocity to the air velocity in a range of 0.7 to 2 when the engine is operating at peak power.

An exhaust gas recirculation mixer, comprising:

• a first fluid inlet configured to receive a first fluid, wherein the first fluid comprises one of air or exhaust gas;
• a second fluid inlet configured to receive a second fluid, wherein the second fluid comprises the other of air or exhaust gas;
• an outer nozzle fluidically connected with the first fluid inlet and configured to direct the first fluid to a throat of a mixing tube;
• an inner nozzle fluidically connected with the second fluid inlet and configured to direct the second fluid to the throat of the mixing tube;
• and
• a controller operable to adjust one or more operating parameters of the exhaust gas recirculation mixer;
• wherein at least a portion of the inner nozzle is nested within the outer nozzle;
• wherein an outer flow path defined by the outer nozzle and an inner flow path defined by the inner nozzle merge at a merge location at which the first fluid has a first velocity and the second fluid has a second velocity;
• and
• wherein the controller is configured to maintain a ratio of the first velocity to the second velocity in a range of 0.7 to 2.