Abstract: A turbofan gas turbine engine includes, in axial flow sequence, a heat exchanger module, a fan assembly, a compressor module, a turbine module, and an exhaust module. The fan assembly includes a plurality of fan blades defining a fan diameter. The heat exchanger module is in fluid communication with the fan assembly by an inlet duct, and the heat exchanger module including a plurality of heat transfer elements for transfer of heat from a first fluid contained within the heat transfer elements to an airflow passing over a surface of the heat transfer elements prior to entry of the airflow into an inlet to the fan assembly. Each heat transfer element may be individually and independently fluidly isolated from the remaining heat transfer elements.

Abstract: A turbofan gas turbine engine includes, in axial flow sequence, a heat exchanger module, a fan assembly, a compressor module, a turbine module, and an exhaust module. The fan assembly includes fan blades defining a fan diameter. The heat exchanger module is in communication with the fan assembly by an inlet duct, and the heat exchanger module further includes radially-extending hollow vanes arranged in a circumferential array, with a channel extending axially between hollow vanes. Each hollow vane accommodates at least one heat transfer element to transfer heat from a first fluid contained within the or each heat transfer element to a corresponding vane airflow passing through the hollow vane and over a surface of the or each heat transfer element. Each hollow vane further includes a flow modulator configured to regulate airflow in proportion to total airflow entering the heat exchanger module in response to a user requirement.

Abstract: A turbofan gas turbine engine includes, in axial flow sequence, a heat exchanger module, a fan assembly, a compressor module, a turbine module, and an exhaust module. The fan assembly includes a plurality of fan blades defining a fan diameter (D). The heat exchanger module is in fluid communication with the fan assembly by an inlet duct, and the heat exchanger module includes a plurality of radially-extending hollow vanes arranged in a circumferential array with a channel extending axially between each pair of adjacent hollow vanes. An airflow entering the heat exchanger module is divided between a set of vane airflows through each of the hollow vanes and a set of channel airflows through each of the channels.

Abstract: A turbofan gas turbine engine includes heat exchanger module, fan assembly, compressor, turbine and exhaust modules. The fan includes a plurality of fan blades. The heat exchanger in fluid communicates with the fan assembly by an inlet duct, and the heat exchanger includes a plurality of radially-extending hollow vanes arranged in a circumferential array, with a channel extending axially between each pair of adjacent hollow vanes. An airflow entering the heat exchanger is divided between a set of vane airflows and a set of channel airflows. Each vane airflow has a vane mass flow rate FlowVane, and each channel air flow has a channel mass flow rate FlowChan. Each hollow vane includes, an inlet, heat transfer, and exhaust portions, with the inlet portion comprising a diffuser element and the heat transfer portion including at least one heat transfer element. The diffuser element causes FlowVane to be lower than FlowChan.

Abstract: A turbofan gas turbine engine comprises, in axial flow sequence, a heat exchanger module, a fan assembly, a compressor module, a turbine module, and an exhaust module. The fan assembly comprises a plurality of fan blades defining a fan diameter (D). The heat exchanger module is in fluid communication with the fan assembly by an inlet duct, and the heat exchanger module comprises a plurality of radially-extending hollow vanes arranged in a circumferential array with a channel extending axially between each pair of adjacent hollow vanes. The heat exchanger module has a square axial cross-sectional profile, where a side length of the square cross-section is D.

Abstract: A turbofan gas turbine engine includes heat exchanger module, fan assembly, compressor, turbine and exhaust modules. The fan includes a plurality of fan blades. The heat exchanger in fluid communicates with the fan assembly by an inlet duct, and the heat exchanger includes a plurality of radially-extending hollow vanes arranged in a circumferential array, with a channel extending axially between each pair of adjacent hollow vanes. An airflow entering the heat exchanger is divided between a set of vane airflows and a set of channel airflows. Each vane airflow has a vane mass flow rate FlowVane, and each channel air flow has a channel mass flow rate FlowChan. Each hollow vane includes, an inlet, heat transfer, and exhaust portions, with the inlet portion comprising a diffuser element and the heat transfer portion including at least one heat transfer element. The diffuser element causes FlowVane to be lower than FlowChan.

Abstract: A turbofan gas turbine engine includes, in axial flow sequence, a heat exchanger module, a fan assembly, a compressor module, a turbine module, and an exhaust module. The fan assembly includes a plurality of fan blades defining a fan diameter. The heat exchanger module is in fluid communication with the fan assembly by an inlet duct, and the heat exchanger module including a plurality of heat transfer elements for transfer of heat from a first fluid contained within the heat transfer elements to an airflow passing over a surface of the heat transfer elements prior to entry of the airflow into an inlet to the fan assembly. Each heat transfer element may be individually and independently fluidly isolated from the remaining heat transfer elements.

Abstract: A turbofan gas turbine engine includes, in axial flow sequence, a heat exchanger module, a fan assembly, a compressor module, a turbine module, and an exhaust module. The fan assembly includes a plurality of fan blades defining a fan diameter (D). The heat exchanger module is in fluid communication with the fan assembly by an inlet duct, and the heat exchanger module includes a plurality of radially-extending hollow vanes arranged in a circumferential array with a channel extending axially between each pair of adjacent hollow vanes. An airflow entering the heat exchanger module is divided between a set of vane airflows through each of the hollow vanes and a set of channel airflows through each of the channels.

Abstract: A turbofan gas turbine engine includes, in axial flow sequence, a heat exchanger module, a fan assembly, a compressor module, a turbine module, and an exhaust module. The fan assembly includes fan blades defining a fan diameter. The heat exchanger module is in communication with the fan assembly by an inlet duct, and the heat exchanger module further includes radially-extending hollow vanes arranged in a circumferential array, with a channel extending axially between hollow vanes. Each hollow vane accommodates at least one heat transfer element to transfer heat from a first fluid contained within the or each heat transfer element to a corresponding vane airflow passing through the hollow vane and over a surface of the or each heat transfer element. Each hollow vane further includes a flow modulator configured to regulate airflow in proportion to total airflow entering the heat exchanger module in response to a user requirement.

Abstract: There is disclosed a variable guide vane device for a gas turbine engine comprising first and second vanes arranged in axial flow series. The first and second vanes are spaced apart so as to define a radially extending slot for fluid flow therebetween.

Abstract: A multispool gas turbine engine for an aircraft application includes a transmission system which is operative to transfer power between relatively rotatable engine spools. In a first mode the transmission system is operative to transfer power from the engine's low pressure spool to its high pressure spool and thereby improve the engine's in-flight relight characteristics; in a second mode it is operative to transfer power from the engine's intermediate pressure spool to its high pressure spool to improve engine part speed performance; and in a third mode to transfer power from the engine's high pressure spool to its intermediate pressure spool to assist in ground starting. With each shaft is an associated flow displacement machine (64,66,62) operable as a pump or motor. In other embodiments, a differential is employed for the power transfer between spools.