Systems and methods for mixing exhaust gases and reductant in an aftertreatment system

• Main Authors: Apoorv Kalyankar, Z Gerald Liu, David Lee Dunnuck, Achuth Munnannur, Niklas M Schmidt
• Format: Patent
• Language: English
• Published: 09.03.2022
• Subjects: BLASTING; ENGINE PLANTS IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNALCOMBUSTION ENGINES; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES ORENGINES IN GENERAL; HEATING; LIGHTING; MACHINES OR ENGINES IN GENERAL; MECHANICAL ENGINEERING; MIXING, e.g. DISSOLVING, EMULSIFYING, DISPERSING; PERFORMING OPERATIONS; PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL; STEAM ENGINES; TRANSPORTING; WEAPONS

A vane swirl mixer for exhaust aftertreatment comprises a vane swirl mixer inlet configured to receive exhaust gas and a vane swirl mixer outlet configured to provide the exhaust gas to a catalyst. It further comprises a first flow device configured to receive the exhaust gas from the vane swirl mixer inlet and to receive a reductant such that the reductant is mixed with the exhaust gas within the first flow device. The first flow device comprises a Venturi body having a Venturi center axis and being defined by a body inlet and a body outlet. The first flow device further comprises a plurality of upstream vanes positioned within the Venturi body and proximate the body inlet. Each of the upstream vanes is coupled to an upstream vane hub. A plurality of upstream vane apertures is interspaced between the plurality of upstream vanes. The plurality of upstream vane apertures is configured to receive the exhaust gas and to cooperate with the plurality of upstream vanes to provide the exhaust gas with a swirl flow that facilitates mixing of the reductant and the exhaust gas. Additionally, the first flow device comprises a plurality of downstream vanes positioned within the Venturi body and proximate the body outlet. Each of the downstream vanes is coupled to a downstream vane hub. A plurality of downstream vane apertures is interspaced between the plurality of downstream vanes. The plurality of downstream vane apertures is configured to receive the exhaust gas and to cooperate with the plurality of downstream vanes to facilitate further mixing of the reductant and the exhaust gas. At least one of the upstream vane hub and the downstream vane hub is radially offset from the Venturi center axis, thereby causing individual ones of the plurality of vanes coupled to the radially offset vane hub to differ in their geometry.