A gas turbine engine comprises a main compressor section having a high pressure compressor with a downstream discharge, and more upstream locations. A turbine section has a high pressure turbine. A tap taps air from at least one of the more upstream locations in the compressor section, passes the tapped air through a heat exchanger and then to a cooling compressor. The cooling compressor compresses air downstream of the heat exchanger, and delivers air into the high pressure turbine. The cooling compressor includes a downstream connection that delivers discharge pressure air to an upstream location in the high pressure turbine and a second tap from an intermediate pressure location within the cooling compressor. The second tap is connected to a downstream location within the high pressure turbine. An intercooling system for a gas turbine engine is also disclosed.

A control system for a gas turbine includes a controller. The controller includes a processor configured to access an operational parameter associated with the gas turbine. The processor is configured to calculate a bias based on the operational parameter, wherein the bias indicates an amount of change in a temperature of an oxidant entering a compressor of the turbine to reach a reference temperature. The processor is further configured to control the temperature of the oxidant based on the bias to improve power output of the gas turbine.

A gas turbine engine includes a turbine section located at an engine central longitudinal axis, a combustor configured to drive rotation of the turbine with combustion products, and a compressor section coupled to the turbine section at the engine central longitudinal axis and driven by the turbine section. An auxiliary compressor is located fluidly between the compressor section and the combustor such that an airflow exiting the compressor section is directed toward the auxiliary compressor. The auxiliary compressor is driven independently from the compressor section and is configured to output the airflow toward the combustor.

A heat exchanger array includes a first row of heat exchangers, a second row of heat exchangers, and side curtains. The first row heat exchangers are spaced apart to define first gaps. The second row heat exchangers are spaced apart to define second gaps and are positioned downstream of and staggered from the first row heat exchangers such that the second row heat exchangers are aligned with the first gaps and the first row heat exchangers are aligned with the second gaps. Each side curtain is in close proximity to a first row heat exchanger and a second row heat exchanger. The side curtains define a neck region upstream of and aligned with each first row heat exchanger and each second row heat exchanger. Each neck region has a neck area that is less than a frontal area of the heat exchanger with which it is aligned.

A method includes compressing an air flow to a first pressure, transferring heat from the air flow to a liquefaction fluid via an intercooler heat exchanger, compressing the air flow to a second pressure greater than the first pressure, combusting the air flow and a fuel to generate a combustion product flow, and driving a turbine with the combustion product flow. The turbine is configured to drive machinery of a liquefaction system. The liquefaction fluid includes at least one of a pre-cooling fluid, a refrigerant, and a liquefied product of the liquefaction system.

A system includes a gas turbine system having a turbine combustor, a turbine driven by combustion products from the turbine combustor, and an exhaust gas compressor driven by the turbine. The exhaust gas compressor is configured to compress and supply an exhaust gas to the turbine combustor. The gas turbine system also has an exhaust gas recirculation (EGR) system. The EGR system is configured to recirculate the exhaust gas along an exhaust recirculation path from the turbine to the exhaust gas compressor. The system further includes a main oxidant compression system having one or more oxidant compressors. The one or more oxidant compressors are separate from the exhaust gas compressor, and the one or more oxidant compressors are configured to supply all compressed oxidant utilized by the turbine combustor in generating the combustion products.

A gas turbine engine comprises a main compressor section having a high pressure compressor, and at least one more upstream compressor. A turbine section has a high pressure turbine. A tap line taps air from at least one of the more upstream compressors in the compressor section, passes the tapped air through a heat exchanger and then to a cooling compressor. The cooling compressor compresses air downstream of the heat exchanger, and delivers air into the high pressure turbine. A bypass valve is positioned downstream of the main compressor section, and upstream of the heat exchanger. The bypass valve selectively delivers air directly to the cooling compressor without passing through the heat exchanger under certain conditions. An intercooling system is also disclosed.

A compressor section for use in a gas turbine engine comprises a compressor rotor having a hub and a plurality of blades extending radially outwardly from the hub and an outer housing surrounding an outer periphery of the blades. A tap taps air at a radially outer first location, passing the tapped air through a heat exchanger, and returning the tapped air to an outlet at a second location which is radially inward of the first location, to provide cooling air adjacent to the hub. A gas turbine engine is also disclosed.

An apparatus and method of cooling a gas turbine engine having a compressor with multiple, axially arranged stages of paired rotating blades and stationary vanes located between an outer compressor casing and inner compressor casing, comprising a closed loop cooling of the compressor by routing a liquid coolant through the vanes of at least some of the compressor stages and through an intercooler to draw heat into the liquid coolant and routing the heated liquid coolant through a heat exchanger comprising a heat exchanger.

A system and method of cooling a gas turbine engine having a compressor with multiple, axially arranged stages of paired rotating blades and stationary vanes located between an outer compressor casing and inner compressor casing, comprising a closed loop cooling of the compressor by extracting compressor air from a first location in the compressor, cooling the extracted air, and introducing the cooled, extracted air at a second location in the compressor, with the second location being upstream of the first location.