Abstract: The present disclosure relates to a positive active material for a lithium rechargeable battery, a manufacturing method thereof, and a lithium rechargeable battery including the positive active material, and it provides a positive active material which is a lithium composite metal oxide including nickel, cobalt, and manganese, and either has orientation in a direction of with respect to an ND axis that is equal to or greater than 29% or has orientation in a direction of [120]+[210] with respect to an RD axis that is equal to or greater than 82% in the case of an EBSD analysis with a misorientation angle (?g) that is equal to or less than 30 degrees.

Abstract: A gas turbine combustor includes a combustion chamber coupled to a nozzle unit that is radially partitioned into plural regions. Each region includes a nozzle casing; a nozzle supplied with fuel and air to produce a mixed gas of the fuel and the air and configured to be inserted into the nozzle casing and to inject the mixed gas into the combustion chamber; a fuel supply section coupled to an outer peripheral surface of the nozzle casing to supply the fuel to the nozzle through the outer peripheral surface; a fuel plenum formed in the nozzle casing to receive the fuel from the fuel supply section; and an air plenum formed in the nozzle casing toward the combustion chamber to receive a portion of the air supplied to the nozzle unit, the portion of air introduced to the air plenum through a first opening formed in the nozzle casing.

Abstract: A helicoidal structure promotes cooling of a liner applied in an annular space of a double-shell structure formed of the liner and a flow sleeve to cool a duct assembly, by increasing the residence time and cooling area of cooling compressed air on the surface of the liner. The helicoidal structure includes a helicoidal rib protruding from a surface of the liner to guide the cooling compressed air at a predetermined angle with respect to an axial direction of the liner, the helicoidal rib having cooling holes and forming a first cooling passage along which main-cooling compressed air flows and a second cooling passage along which auxiliary-cooling compressed air flows. The second cooling passage induces a flow of the auxiliary-cooling compressed air through the cooling holes, and the flow of the auxiliary-cooling compressed air is derived from a flow of the main-cooling compressed air in the first cooling passage.

Abstract: A gas turbine combustor includes a combustion chamber coupled to a nozzle unit that is radially partitioned into plural regions. Each region includes a nozzle casing; a nozzle supplied with fuel and air to produce a mixed gas of the fuel and the air and configured to be inserted into the nozzle casing and to inject the mixed gas into the combustion chamber; a fuel supply section coupled to an outer peripheral surface of the nozzle casing to supply the fuel to the nozzle through the outer peripheral surface; a fuel plenum formed in the nozzle casing to receive the fuel from the fuel supply section; and an air plenum formed in the nozzle casing toward the combustion chamber to receive a portion of the air supplied to the nozzle unit, the portion of air introduced to the air plenum through a first opening formed in the nozzle casing.

Abstract: A helicoidal structure promotes cooling of a liner applied in an annular space of a double-shell structure formed of the liner and a flow sleeve to cool a duct assembly, by increasing the residence time and cooling area of cooling compressed air on the surface of the liner. The helicoidal structure includes a helicoidal rib protruding from a surface of the liner to guide the cooling compressed air at a predetermined angle with respect to an axial direction of the liner, the helicoidal rib having cooling holes and forming a first cooling passage along which main-cooling compressed air flows and a second cooling passage along which auxiliary-cooling compressed air flows. The second cooling passage induces a flow of the auxiliary-cooling compressed air through the cooling holes, and the flow of the auxiliary-cooling compressed air is derived from a flow of the main-cooling compressed air in the first cooling passage.