US 12,378,924 B1
Systems and methods for migitating cold start emissions via rotation of turbocharger turbine
Maqsood Rizwan Ali Khan, Troy, MI (US); Mark Claywell, Birmingham, MI (US); and Azeem Sarwar, Rochester Hills, MI (US)
Assigned to GM GLOBAL TECHNOLOGY OPERATIONS LLC, Detroit, MI (US)
Filed by GM GLOBAL TECHNOLOGY OPERATIONS LLC, Detroit, MI (US)
Filed on Oct. 2, 2024, as Appl. No. 18/904,950.
Int. Cl. F02D 41/00 (2006.01); F02D 41/02 (2006.01); F02D 41/06 (2006.01)
CPC F02D 41/0007 (2013.01) [F02D 41/0255 (2013.01); F02D 41/064 (2013.01); F02D 2250/34 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A method of mitigating cold start emissions in a vehicle via rotation of a turbine of a turbocharger comprising:
receiving at a controller, a trigger signal from a trigger signal source, wherein the trigger signal comprises a vehicle turn on signal and the trigger signal source comprises a vehicle turn on button; and
prior to turning on an engine of the vehicle:
issuing by the controller, a first control signal to a wastegate actuator to open a wastegate responsive to the trigger signal; and
issuing by the controller, a second control signal to a turbo shaft actuator to rotate the turbine of the turbocharger in a reverse rotation, wherein the reverse rotation of the turbine causes recirculated air to flow in a reverse recirculation flow path comprising an exhaust manifold, the turbine, an exhaust wall system, and the wastegate, wherein:
the exhaust wall system comprises a turbine housing of the turbine, exhaust walls disposed between the turbine and the wastegate, and exhaust walls disposed between the turbine and a catalyst brick;
at least a portion of the reverse recirculation flow path is adjacent a side of the catalyst brick;
heat transfer occurs from the recirculated air to the exhaust wall system and to the catalyst brick via the side of the catalyst brick; and
the recirculated air comprises air that remained in the exhaust manifold after the engine was previously turned off and air from an intake manifold through the engine to an outlet of the turbine via the exhaust manifold due to an overlap in a partial opening of an intake valve with respect to an exhaust value of at least one cylinder of the engine when the engine was previously turned off.