Abstract: The present invention effectively cools members with a small amount of cooling air. Turbulence promotor ribs are formed so that cooling fluid along a wall flows from a center of the wall to both end portions of the wall. A highly enhanced thermal conducting effect, namely high cooling heat transfer coefficient, can be obtained, and it is possible to cool members effectively with the small amount of cooling air.

Abstract: A blade for a gas turbine has a leading edge portion which has an arc-shaped cross-section, and a maximum thickness portion of the blade is located within this arc. With this blade configuration, an abrupt acceleration of hot gas at the leading edge portion of the blade is restrained, so that the velocity of the hot gas at the blade surface can be made low. Therefore, the heat transfer coefficient from the hot gas to the blade wall is lowered, so that the amount of cooling air required to be passed through the interior of the blade can be reduced.

Abstract: A method of starting wherein the gas turbine, a gas turbine is started while injecting a prescribed amount of moisture into a combustor or a path for combustion gas from start up of the gas turbine, and the amount of moisture is varied in dependence upon the feed quantity of fuel or the temperature of the combustion gas so that combustion temperature in the combustor or temperature variation rate of the surfaces of component parts of the gas path is approximately constant.

Abstract: A cooling structure for a turbine blade. Comprising a hollow-structured main body and a cooling medium discharging device located in the inner cavity of the hollow-structured main body and formed to discharge a cooling medium from the surface thereof, so that the cooling medium discharged from the cooling medium discharging device impinges against the inner surface of the main body to remove the heat from the same. The turbine blade further includes a projection formed on the inner surface of the leading edge of the main body, extending along the spanwise direction of the blade, and the cooling medium discharging device is formed to allow at least part of the cooling medium to directly impinge against proximal portions of the projection. With this arrangement, a turbine blade is provided which allows a small amount of cooling air to cool the turbine blade and its leading edge in particular with great effectiveness.