Method and apparatus for the start-up and control of pulse combustors using selective injector operation

A deflagration pulse combustor system with improved startup and control comprising:

• a deflagration pulse combustor further comprising
• an inlet pipe having a proximal and distal end, with the inlet pipe having a first length and being in fluid communication with a combustion chamber,
• an exhaust pipe having a proximal and distal end, with the exhaust pipe having a second length greater than the first length of the inlet pipe and being in fluid communication with the combustion chamber,
• the combustion chamber having a first end having a first opening for connecting to the proximal end of the inlet pipe for fluid communication between the combustion chamber and the inlet pipe and a second end having a second opening for connecting to the proximal end of the exhaust pipe for fluid communication between the combustion chamber and exhaust pipe,
• a plurality of three or more fuel injectors disposed around at least the inlet pipe or the combustion chamber for injecting fuel under pressure into the inlet pipe or combustion chamber for mixing with air ingressing from the distal end of the inlet pipe to form combustible fuel-air mixtures,
• an ignition subsystem disposed on the combustion chamber for providing means for igniting discrete fuel-air mixtures within the combustion chamber to cause combustion events, with each combustion event causing gas jets to be output from the distal ends of the inlet and exhaust pipes, and
• a sensor subsystem for continuously monitoring predetermined physical properties within the combustion chamber and generating output electrical signals representative of operating states of the deflagration pulse combustor that includes at least a pre-startup operating state and a plurality of continuous operating states after pulse combustor startup;
• and
• an air supply subsystem with a capability to provide air under predetermined pressure into the inlet pipe;
• a fuel supply subsystem with a capability to provide fuel under predetermined pressure to the plurality of fuel injectors;
• and
• a deflagration pulse combustor controller electrically connected to the air supply subsystem, the plurality of fuel injectors, the ignition subsystem, and the sensor subsystem, with the deflagration pulse combustor controller electrically controlling the air subsystem, the fuel supply subsystem, the plurality of fuel injectors, and the ignition subsystem, and receiving electrical signals from the sensor subsystem, and with the deflagration pulse combustor controller further controlling selective activation and deactivation of fuel injectors of the plurality of fuel injectors for start-up and each of the plurality of continuous operating states of the deflagration pulse combustor to increase a throttle range of the deflagration pulse combustor, including changing the activation and deactivation of fuel injectors during any continuous operating state and such activation and deactivation of the fuel injectors for portions of, or during, a maximum duty cycle of the deflagration pulse combustor and when fewer than a total number of fuel injectors are activated, the activated fuel injector(s) are operated for a longer duty cycle than when the total number of fuel injectors are activated;
• wherein in a mode of operation, all the plurality of fuel injectors are used simultaneously during the maximum duty cycle.