Rotary internal combustion engine with variable volumetric compression ratio

A method of controlling an air intake in a rotary engine (210; 310; 410), the engine having at least one primary and one secondary intake port (140; 440; 242; 442) in communication with an air source and an exhaust port (244; 244; 44), the procedure comprising: during engine start-up, close the main inlet port (140; 440) and open the secondary inlet port (242; 442), the exhaust port being secondary input (242; 442) located rearward of the main inlet port (140; 440) and forward of the exhaust port (244; 304; 44) along a direction of one revolution of an engine rotor (24); after start-up and with a power demand on the motor below a predetermined threshold, opening the main inlet port (140; 440) and at least partially closing the secondary inlet port (242; 442); and when the power demand exceeds the predetermined threshold, leaving the main inlet port (140; 440) open and opening the secondary inlet port (242; 442), the secondary inlet port (242; 442) being located so that that is in communication with the exhaust port (244; 344; 44) throughout portions of the engine revolution to purge exhaust gases from the engine.