• ANSYS
• Bypass Valve
• Light off
• Solidworks
• Three Way Catalyst

The Three-Way Catalyst (TWC) is one of the most significant inventions in recent history. When used correctly, it can eliminate the majority of pollutant emissions from internal combustion engines, particularly in spark-ignited engines.
To achieve such performance, it is essential to accurately control the air-fuel ratio and ensure the TWC reaches the so-called light-off temperature as quickly as possible. If these conditions are not respected, the pollutant conversion efficiency of the TWC is drastically reduced.
The presented work represents the continuation of the research work made by four students. Their studies confirmed through 0-dimensional models and fluid dynamic simulations that bypassing the turbine, in the exhaust system of a turbocharged spark-ignited engine, can be beneficial for achieving the light-off temperature in the shortest possible time.
The aim of this thesis is to design and validate, through fluid dynamic simulations, a valve to be inserted in the bypass.
This valve will not only allow the opening and closing of the bypass but will also improve its performance by increasing the amount of exhaust gases passing through it.

The Three-Way Catalyst (TWC) is one of the most significant inventions in recent history. When used correctly, it can eliminate the majority of pollutant emissions from internal combustion engines, particularly in spark-ignited engines. To achieve such performance, it is essential to accurately control the air-fuel ratio and ensure the TWC reaches the so-called light-off temperature as quickly as possible. If these conditions are not respected, the pollutant conversion efficiency of the TWC is drastically reduced. The presented work represents the continuation of the research work made by four students. Their studies confirmed through 0-dimensional models and fluid dynamic simulations that bypassing the turbine, in the exhaust system of a turbocharged spark-ignited engine, can be beneficial for achieving the light-off temperature in the shortest possible time. The aim of this thesis is to design and validate, through fluid dynamic simulations, a valve to be inserted in the bypass. This valve will not only allow the opening and closing of the bypass but will also improve its performance by increasing the amount of exhaust gases passing through it.