Rotary engine rotor and method

A rotor for a rotor, comprising:

• a rotor body having:
• a plurality of peripheral surfaces disposed around an exterior perimeter of the rotor body;
• a plurality of seats, each respective seat disposed in a respective peripheral surface;
• and
• a plurality of recess members, each said recess member a structure independent of the rotor body, and each said recess member is attached to the rotor body;
• wherein the rotor is configurable in a first configuration and a second configuration;
• in the first configuration the plurality of recess members are first recess members, each said first recess member having a first interior cavity open to an exterior of the rotor body, the first interior cavity having a first geometric configuration;
• and
• in the second configuration the plurality of recess members are second recess members, each said second recess member having a second interior cavity open to the exterior of the rotor body, the second interior cavity having a second geometric configuration;
• wherein the first geometric configuration is different from the second geometric configuration, and wherein the first geometric configuration is based on combustion of a first fuel type, and the second geometric configuration is based on combustion of a second fuel type, and the first fuel type and the second fuel type are different;
• and
• wherein each said seat is configured to interchangeably receive a respective first recess member or a respective second recess member, and in the first configuration of the rotor each respective seat receives a respective first recess member, and in the second configuration of the rotor each respective seat receives a respective second recess member.