A New Approach to Low-Cost High-Efficiency Automotive Gas Turbines

The automotive gas turbine has not been adopted for many reasons, among which are that the materials required have been expensive, and the fuel consumption has been unremarkable. A new approach is to use a marked reduction in blade speeds (and therefore in blade and disk stresses) through multistaging, allowing the use of injection-molded compressor components and low-cost ceramic materials (e.g. technology developed for automotive turbochargers) for all hot parts. The pressure ratio will also be lowered and the heat-exchanger effectiveness increased. The resulting engine is larger than existing experimental turbines but still smaller and lighter than an equivalent spark-ignition or compression-ignition engine, with a marked improvement in projected fuel efficiency.