Combustion device and gas turbine

A combustion device, comprising:

• a nozzle casing defining an axial flow passage;
• and
• a nozzle disposed in the axial flow passage,
• wherein the nozzle includes:
• a nozzle body having a tubular shape extending along the axial flow passage;
• a swirler vane protruding radially outward from the nozzle body in a radial direction of the nozzle body, the swirler vane being configured to swirl a fluid flowing through the axial flow passage;
• at least one first injection hole having an opening on a surface of the nozzle body or the swirler vane;
• at least one second injection hole having an opening on the surface of the nozzle body or the swirler vane;
• a first fuel flow passage extending through the nozzle body and being in communication with the at least one first injection hole;
• and
• a second fuel flow passage extending through the nozzle body separately from the first fuel flow passage, and being in communication with the at least one second injection hole,
• wherein the combustion device further comprises:
• a first supply flow passage capable of supplying a first fuel to the first fuel flow passage;
• and
• a second supply flow passage capable of supplying a second fuel other than the first fuel to the second fuel flow passage,
• wherein the first fuel has a smaller calorific value than the second fuel, and
• wherein a ratio of a total area of the first injection hole to a total area of the second injection hole is determined on the basis of a ratio of the calorific value of the first fuel to the calorific value of the second fuel.