University of Bath

Additive manufacturing for cooled high-temperature automotive radial machinery (CHARM)

Assessing the technical feasibility of producing additively manufactured cooled high-temperature capable radial turbomachinery in nickel superalloys.

Our business-led project will assess the technical feasibility of designing and manufacturing high-temperature high-speed turbine components. It will use a laser powder bed additive process, capable of operating in the harsh environment found in automotive turbochargers.

We can increase current temperature limits imposed at the turbine entry by air-cooling the turbine wheel. This allows for the use of materials with maximum operating temperatures below the gas temperature. This is a key enabler for downsized IC engines, both saving weight and reducing CO2 emissions. Air-cooling through the turbine wheel removes the need for integrated exhaust manifolds that cool the air pre-turbine. It also allows manufacturers to run with no overfuelling, widely used as a cooling method in current engines.

We will design and manufacture cooled and uncooled radial turbine wheels using additive methods. We will demonstrate the improved performance of the cooled wheel experimentally in a gas stand test facility and through the use computational fluid dynamics (CFD).

Additive manufacturing as a technology opens up a wide range of component and system-level options with the potential for weight savings across the automotive engine. Based on current machine and process developments and technical roadmaps, it is likely that this will be a core technology by 2025.