| 摘要 |
A passive secondary air delivery system for a two bed catalyst is provided. The system delivers passive secondary air to the second catalyst bed to facilitate oxidation of CO and remaining unburned HC. In a turbocharged engine, the secondary air may be provided from the compressor side of the turbocharger. Control of the amount of air bled from the turbocharger is provided by an orifice in the pipe connecting the turbocharger to the catalyst bed. No active controls are required. In non-turbocharged engines, passive secondary air may be provided by a venturi mixer ported to ambient positioned between the two catalyst beds. In either embodiment, no moving parts or active controls are required. |
