8870 results about "Combustor" patented technology

The invention relates to the technical field of control and regulation systems, in particular to a hearth auxiliary regulation control system which comprises a data processing module, an analysis module, a control module, a regulation and control module, an optimization module and a safety early warning module. The data processing module collects temperature data of a hearth combustor area, a water cooling wall and a tail flue in real time through a distributed temperature sensor network, and a dynamic combustion field three-dimensional model is generated through Kalman filtering denoising, redundancy cross validation and a temperature compensation algorithm in combination with combustor flame position signals and an air door opening state. And the optimization module updates the strategy weight based on the combustion efficiency improvement rate, and reinforces learning to extend the adaptive boundary of the strategy library. And the safety early warning module calculates the matching coefficient of the pipe wall temperature and the allowable stress in real time, triggers a grading intervention strategy to reduce the overtemperature risk, forms full-process closed-loop control, and improves the thermal efficiency and the operation safety of the boiler.

A method of operating a gas turbine engine including: an engine core with a turbine, compressor, a fuel combustor, and a core shaft connecting the turbine to the compressor; a fan; a gearbox that receives an input from the core shaft and outputs drive to the fan; an oil loop system arranged to supply oil to the gearbox; and a heat exchange system including: an air-oil heat exchanger through which the oil flows; a fuel-oil heat exchanger through which the oil and the fuel flow; a temperature sensor downstream of the fuel-oil heat exchanger; and a valve arranged to allow oil or air flow rate through at least one heat exchanger to be varied, the method including: determining if the fuel temperature has increased above a set threshold at cruise conditions; and in response, controlling the valve so as to change the flow rate through the heat exchanger.

The invention relates to the technical field of steam turbine testing, in particular to a testing system for mismatch correction of a wide-load-interval thermal power generating unit speed regulation model, which comprises a thermodynamic system component, a speed regulation system device, a dynamic signal acquisition device and a control device, a dynamic signal processing module analyzes the relevance between main steam pressure sudden change and control valve opening oscillation in real time, a dynamic response database including a time sequence is constructed, and a control valve opening feed-forward compensation instruction and a combustor fuel distribution gradient adjustment signal are generated according to correction parameters. Power over-modulation wave crests caused by sudden load change are suppressed, and primary frequency modulation action delay is reduced; and the simulation verification module compares measured data with model output through an error feedback mechanism, dynamically adjusts high-pressure cylinder flow characteristic curve calibration parameters, optimizes a control strategy in combination with a network-related safety margin evaluation result, and realizes improvement of dynamic response precision in a full peak regulation interval and enhancement of power grid frequency stability.

The invention relates to the technical field of mechanical stress and thermal deformation monitoring, in particular to a combustion fine adjustment method based on full-hearth expansion monitoring, which is characterized in that expansion sensor arrays are arranged on each layer of a main burner area of a boiler hearth, and vibration monitoring units are arranged in a layered manner from a main burner to an SOFA air area synchronously; normal deformation, three-dimensional expansion displacement data and vibration spectrum data of the four furnace walls are collected; generating a standardized monitoring data set through wavelet noise reduction and temperature compensation processing, fusing boiler operation parameters, and inputting the boiler operation parameters into the reinforcement learning model to generate a combustor adjustment instruction; water-cooled wall expansion rate change data is collected in real time to optimize model weight and update a control strategy, and a closed-loop feedback mechanism is formed. According to the method, through multi-source sensing data fusion and dynamic modeling, sub-meter analysis of thermal load distribution and quick response of the combustion state are achieved, the boiler operation efficiency is improved, and the service life of equipment is prolonged.

An aircraft gas turbine engine includes a combustor, with a combustion chamber and fuel spray nozzles to inject fuel into the chamber. The nozzles include first and second subsets. The first subset of nozzles is supplied with fuel at a greater rate than each of the second subset. A ratio of nozzles in the first subset to the second subset is 1:3 to 1:6. A lean cruise nvPM emissions index ratio isEIcruise⁡(lean),SAFEIcruise⁡(lean),FF,where EIcruise(lean),SAF isEImaxTO,SAF+EIclimb,SAF2and EIcruise(lean),FF isEImaxTO,FF+EIclimb,FF2.EImaxTO,SAF is nvPM emissions index operating at 100% available thrust and EIclimb,SAF is the nvPM emissions index operating at 85% available thrust if fuel includes sustainable aviation fuel. EImaxTO,FF is the nvPM emissions index operating at 100% available thrust and EIclimb,FF is the nvPM emissions index at 85% available thrust if fuel is a fossil-based hydrocarbon. The lean cruise nvPM emissions index ratio is less than 1.

A gas turbine engine for an aircraft is disclosed. The gas turbine engine comprises: a combustor, comprising a combustion chamber and a plurality of fuel spray nozzles configured to inject fuel into the combustion chamber, wherein the plurality of fuel spray nozzles comprises a first subset of fuel spray nozzles and a second subset of fuel spray nozzles, wherein the combustor is operable in a condition in which each of the fuel spray nozzles of the first subset of fuel spray nozzles is supplied with fuel at a greater fuel flow rate than each of the fuel spray nozzles of the second subset of fuel spray nozzles, wherein a ratio of the number of fuel spray nozzles in the first subset of fuel spray nozzles to the number of fuel spray nozzles in the second subset of fuel spray nozzles is in the range of 1:2 to 1:5. A thrust nvPM emissions index ratio is defined as:EImaxTO / FmaxTOEIidle / Fidlewhere: EIidle is the system loss corrected nvPM emissions index in mg / kg of the gas turbine engine if operating at around 7% available thrust for given operating conditions; EImaxTO is the system loss corrected nvPM emissions index in mg / kg of the gas turbine engine if operating at around 100% available thrust for the given operating conditions; FmaxTO is the thrust of the gas turbine engine at around 100% available thrust in kN for the given operating conditions; and Fidle is the thrust of the gas turbine engine at around 7% available thrust in kN for the given operating conditions. The thrust nvPM emissions index ratio is greater than 0.001. The gas turbine engine is configured to provide fuel comprising a sustainable aviation fuel (SAF) to the plurality of fuel spray nozzles. Also disclosed is a method of operating the gas turbine engine.

Systems and methods for providing lubrication to a gas turbine engine are described. An example gas turbine engine includes a plurality of bearings disposed along an axial length of a rotatable shaft to provide rotational support between a static structure and at least one of a compressor and a turbine of the gas turbine engine. The gas turbine engine further includes a fuel system operable to deliver a mixture of fuel and lubricant sequentially to at least one of the plurality of bearings and the combustor so that during operation of the gas turbine engine, at least the lubricant within the mixture is in a liquid phase prior to being received by the at least one of the plurality of bearings, and in a vapor phase once the lubricant is delivered to the at least one of the plurality of bearings.

A gas turbine engine for an aircraft is disclosed. The gas turbine engine comprises: a combustor, comprising a combustion chamber and a plurality of fuel spray nozzles configured to inject fuel into the combustion chamber, wherein the plurality of fuel spray nozzles comprises a first subset of fuel spray nozzles and a second subset of fuel spray nozzles, wherein the combustor is operable in a condition in which each of the fuel spray nozzles of the first subset of fuel spray nozzles is supplied with fuel at a greater fuel flow rate than each of the fuel spray nozzles of the second subset of fuel spray nozzles, wherein a ratio of the number of fuel spray nozzles in the first subset of fuel spray nozzles to the number of fuel spray nozzles in the second subset of fuel spray nozzles is in the range of 1:3 to 1:6. A MTO nvPM emissions index ratio is defined as:EImaxTO,SAFEImaxTO,FFwhere: EImaxTO,SAF is the system loss corrected nvPM emissions index in mg / kg of the gas turbine engine when operating at around 100% available thrust for given operating conditions if a fuel provided to the plurality of fuel spray nozzles comprises a sustainable aviation fuel (SAF); and EImaxTO,FF is the system loss corrected nvPM emissions index in mg / kg of the gas turbine engine when operating at around 100% available thrust for the given operating conditions if a fuel provided to the plurality of fuel spray nozzles is a fossil-based hydrocarbon fuel. The MTO nvPM emissions index ratio of the gas turbine engine is less than 1. The gas turbine engine is configured to provide fuel comprising a SAF to the plurality of fuel spray nozzles. Also disclosed are methods of operating the gas turbine engine.

Disclosed is a water heater including a case provided with an air supply hole and an air discharge hole, a burner provided in an interior of the case, and a humidified air supply part that provides humidified air to the burner together with a fuel. The humidified air supply part includes a first accommodation tank that accommodates water to generate vapor, and a humidified air supply tank that provides a space for supplying the vapor supplied from the first accommodation tank to air introduced into an interior of the case through the air supply hole.

A gas turbine engine for an aircraft. The gas turbine engine comprising: a combustor, comprising a combustion chamber and a plurality of fuel spray nozzles configured to inject fuel into the combustion chamber, wherein the plurality of fuel spray nozzles comprises a first subset of fuel spray nozzles and a second subset of fuel spray nozzles, wherein the combustor is operable in a condition in which each of the fuel spray nozzles of the first subset of fuel spray nozzles is supplied with fuel at a greater fuel flow rate than each of the fuel spray nozzles of the second subset of fuel spray nozzles, wherein a ratio of the number of fuel spray nozzles in the first subset of fuel spray nozzles to the number of fuel spray nozzles in the second subset of fuel spray nozzles is in the range of 1:2 to 1:5. An MTO nvPM emissions index ratio-modified fuel flow is defined as:EImaxTO,SAFEImaxTO,FF×Wf,maxTOwhere: EImaxTO,SAF is the system loss corrected nvPM emissions index in mg / kg of the gas turbine engine when operating at around 100% available thrust for given operating conditions if a fuel provided to the plurality of fuel spray nozzles comprises a sustainable aviation fuel (SAF); EImaxTO,FF is the system loss corrected nvPM emissions index in mg / kg of the gas turbine engine when operating at around 100% available thrust for the given operating conditions if a fuel provided to the plurality of fuel spray nozzles is a fossil-based hydrocarbon fuel; and Wf,maxTO is the mass flow rate of fuel provided to the plurality of fuel spray nozzles in kg / s when the gas turbine engine is operating at around 100% available thrust for the given operating conditions. The MTO nvPM emissions index ratio-modified fuel flow of the gas turbine engine in kg / s is less than 2. The gas turbine engine is configured to provide fuel comprising a SAF to the plurality of fuel spray nozzles. Also disclosed is a method of operating the gas turbine engine.

A gas turbine engine includes a combustor with a combustion chamber and fuel spray nozzles to inject fuel into the combustion chamber. The nozzles include a first and second subset. Each of the nozzles of the first subset is supplied with fuel at a greater rate than each of the second subset. A ratio of nozzles in the first subset to nozzles in the second subset from 1:3 to 1:6. A fuel-flow nvPM emissions index ratio isEIidle×Wf,idleRImaxTO×Wf,maxTO.EIidle and EImaxTO are the system loss corrected nvPM emissions index in mg / kg operating at around 7% and 100% available thrust for the given operating conditions, respectively. Wf,idle and Wf,maxTO are the rate of fuel flow to the fuel spray nozzles in kg / s at around 7% and 100% available thrust for the given operating conditions, respectively. The fuel-flow nvPM emissions index ratio of the gas turbine engine is less than 0.3.

A turbine engine for an aircraft including a combustor, a turbine, and a steam system. The combustor generates combustion gases. The turbine receives the combustion gases and is drivingly coupled to a shaft. The steam system includes a boiler, a superheater, and a steam turbine. The boiler receives water and is fluidly connected to the combustor to receive a first portion of the combustion gases from the combustor and to boil the water to generate steam. The superheater is located downstream of the combustor to receive a second portion of the combustion gases from the combustor and to heat the steam. The steam turbine is fluidly coupled to the superheater to receive the steam from the superheater and to rotate the steam turbine. The steam turbine is drivingly coupled to the shaft.

A gas turbine engine includes: a rich burn, quick quench, lean burn combustor having a number of fuel spray nozzles in the range 14-22 or a number of fuel spray nozzles per unit engine core size in the range 2 to 6. An nvPM emissions index ratio is defined as:EIidle×Wf,idleEImaxTO×Wf,maxTOwhere: EIidle and EImaxTO are respectively the nvPM emissions index in mg / kg of gas turbine engine if operating at around 7% or 100% available thrust for given operating conditions; Wf,idle and Wf,maxTO are respectively the rate of fuel flow to fuel spray nozzles in kg / s at around 7% or 100% available thrust for given operating conditions. The fuel-flow nvPM emissions index ratio is less than 0.08. The gas turbine engine is configured to provide fuel including sustainable aviation fuel to fuel spray nozzles. Also disclosed is a method of operating the gas turbine engine.

A gas turbine engine for an aircraft. The gas turbine engine comprising: a rich burn, quick quench, lean burn (RQL) combustor having a number of fuel spray nozzles in the range of 14-22 or a number of fuel spray nozzles per unit engine core size in the range 2 to 6. An MTO nvPM emissions index ratio is defined as:EImaxTO,SAFEImaxTO,FFwhere: EImaxTO,SAF is the system loss corrected nvPM emissions index in mg / kg of the gas turbine engine when operating at around 100% available thrust for given operating conditions if a fuel provided to the fuel spray nozzles comprises a sustainable aviation fuel (SAF); and EImaxTO,FF is the system loss corrected nvPM emissions index in mg / kg of the gas turbine engine when operating at around 100% available thrust for the given operating conditions if a fuel provided to the fuel spray nozzles is a fossil-based hydrocarbon fuel. The MTO nvPM emissions index ratio of the gas turbine engine is less than 1. The gas turbine engine is configured to provide fuel comprising a SAF to the fuel spray nozzles. Also disclosed is a method of operating a gas turbine engine.

A gas turbine engine for an aircraft is disclosed. The gas turbine engine comprises: a combustor, comprising a combustion chamber and a plurality of fuel spray nozzles configured to inject fuel into the combustion chamber, wherein the plurality of fuel spray nozzles comprises a first subset of fuel spray nozzles and a second subset of fuel spray nozzles, wherein the combustor is operable in a condition in which each of the fuel spray nozzles of the first subset of fuel spray nozzles is supplied with fuel at a greater fuel flow rate than each of the fuel spray nozzles of the second subset of fuel spray nozzles, wherein a ratio of the number of fuel spray nozzles in the first subset of fuel spray nozzles to the number of fuel spray nozzles in the second subset of fuel spray nozzles is in the range of 1:3 to 1:6. A MTO nvPM emissions index ratio is defined as:EImaxTO,SAFEImaxTO,FFwhere: EImaxTO,SAF is the nvPM emissions index in mg / kg of the gas turbine engine when operating at around 100% available thrust for given operating conditions if a fuel provided to the plurality of fuel spray nozzles comprises a sustainable aviation fuel (SAF); and EImaxTO,FF is the nvPM emissions index in mg / kg of the gas turbine engine when operating at around 100% available thrust for the given operating conditions if a fuel provided to the plurality of fuel spray nozzles is a fossil-based hydrocarbon fuel. The MTO nvPM emissions index ratio of the gas turbine engine is less than 1. The gas turbine engine is configured to provide fuel comprising a SAF to the plurality of fuel spray nozzles. Also disclosed are methods of operating the gas turbine engine.

A gas turbine engine includes: a rich burn, quick quench, lean burn combustor having a number of fuel spray nozzles in range of 14-22 or a number of fuel spray nozzles per unit engine core size in range 2 to 6. An MTO nvPM emissions index ratio is:EImaxTO,SAFEImaxTO,FF×Wf,maxTOwhere: EImaxTO,SAF and EImaxTO,FF are respectively the nvPM emissions index in mg / kg when operating around 100% available thrust for given operating conditions if fuel provided to fuel spray nozzles includes either sustainable aviation fuel (SAF) or fossil-based hydrocarbon fuel; Wf,maxTO is mass flow rate of fuel provided to fuel spray nozzles in kg / s when gas turbine engine is operating at around 100% available thrust for given operating conditions. MTO nvPM emissions index is less than 2. The gas turbine engine is configured to provide fuel including SAF to fuel spray nozzles. Also disclosed is method of operating gas turbine engine.

The invention relates to the technical field of pulverized coal fired boiler combustors, and particularly discloses a double-high-concentration-area oil-saving ignition pulverized coal combustor. The double-high-concentration-area oil-saving ignition pulverized coal burner comprises a flow guide device and an ignition device arranged in a combustion cylinder. The flow guide device comprises a main cylinder and a turbulent flow structure arranged on the periphery of the main cylinder, the main cylinder is connected to the inner wall of the combustion cylinder through a supporting piece, and the turbulent flow structure is of a structure protruding in the radial direction and used for disturbing the flow direction of mixed gas. Therefore, the problem that in the prior art, when the structural design of an oil-saving ignition pulverized coal burner is in a non-ignition working condition, the pulverized coal concentration distribution mode of'thick inside and thin outside 'is opposite to the design of'thick outside and thin inside' of an original burner of a boiler, and the air powder flow field characteristics of an outlet of the burner and the interior of a hearth are prone to being remarkably influenced is solved.

A gearbox assembly includes a gearbox and a gutter for collecting a gearbox lubricant scavenge flow from the gearbox. The gutter is characterized by a lubricant extraction volume ratio between 0.01 and 0.3 that is defined byVGVG⁢B.VG is a gutter volume of the gutter and VGB is a gearbox volume. A gas turbine engine includes the gearbox assembly, a fan, a combustor that generates combustion gases, a turbine, a nacelle that surrounds the fan, and a steam system. The combustor and the turbine define a core air flowpath. Core air flows through the core air flowpath. The steam system that extracts water from the combustion gases, vaporizes the water to generate steam, and injects the steam into the core air flowpath to add mass flow to the core air. A bypass ratio of the gas turbine engine is in a range of 18:1 to 100:1.

Systems and methods of the present disclosure includes a mixer configured to mix air and hydrocarbons and a burner configured to receive the mixed air and hydrocarbons and to generate syngas. The system also includes a cooling system configured to receive the syngas and to cool the syngas to form cooled syngas. The system further includes a collector configured to collect carbon from the cooled syngas as soot. Moreover, the system includes a flare stack configured to receive the cooled syngas and to burn off at least part of the cooled syngas.

The invention discloses a machine learning multi-objective optimization control method based on coal quality characteristics and combustion state feedback, and belongs to the technical field of industrial process automatic control. According to the method, collaborative optimization control over the combustion efficiency, NOx emission and combustion stability is achieved under the multi-working-condition operation condition of the combustor. According to the method, coal quality characteristic parameters and combustion state data are collected, working condition clustering is carried out after data fusion, and a historical combustion operation data set coupling coal quality characteristics and combustion states is constructed; a combustion state evaluation model and a combustion control model are established by adopting machine learning, on the basis of identifying working conditions in real time and evaluating combustion performance, a control parameter adjustment amount is generated in combination with trend extrapolation and a multi-objective cost function, and a combustion state feedback rolling correction model and a control strategy are utilized to realize combustion control. The self-adaptive closed-loop collaborative optimization control of the combustion process under multiple coal types and multiple working conditions is realized, the boiler efficiency is improved, the NOx emission is reduced, and the operation robustness is enhanced.

An aircraft propulsion system includes a series of condensers where water is condensed from the exhaust gas flow. Each of the series of condensers define a passage for exhaust gas flow such that water recovered from the exhaust gas flow drains at a downward angle in a direction of gravity through each of the series of condensers. A series of water separators separate the exhaust gas flow from water condensed in a corresponding one of the series of condensers and the water is transformed into a steam flow in an evaporator system for communication to the combustor.

The invention relates to a clean energy combustion technology, and aims to provide a rotational flow on-duty multi-element micro-mixing coupling type low-nitrogen combustion device for hydrogen-doped natural gas. Comprising an air cooling cavity, an air bin fixing cavity and a gas bin fixing cavity which are sequentially stacked from top to bottom. An on-duty combustion unit of a sleeve structure is arranged in the center of the burner in a penetrating mode, and micro-mixing combustion units, independent air bins and independent fuel gas bins are evenly arranged in the circumferential direction in a surrounding mode. A plurality of micro-mixing spray pipes are arranged in an air cooling sleeve of the micro-mixing combustion unit in the axial direction in an array mode, and fuel spray pipes are arranged on a second fixed disc in the axial direction in an array mode. The closed end of the fuel spray pipe extends into the micro-mixing spray pipe corresponding to the fuel spray pipe, and a fuel gas inlet is formed in the bottom of the fuel gas bin fixing cavity. After external air is introduced through an air circulation path from top to bottom to cool the head of the combustor, the heated air is mixed with fuel for combustion, and safe, efficient and low-emission application of natural gas large-proportion hydrogen-doped fuel is achieved.

The invention relates to the technical field of boiler control, and discloses a gas-fired boiler starting control method and system. The method comprises the following steps: acquiring initial operation parameters such as hearth pressure, water inlet temperature, flue gas oxygen content and fuel valve opening of the gas-fired boiler, establishing a thermodynamic state model in a starting stage according to the initial operation parameters, and dividing dynamic response thresholds of different load intervals; and calculating a theoretical fuel supply rate of the combustor based on the model, generating and dynamically updating a fuel supply correction coefficient in combination with a threshold value, synchronously marking key nodes according to abnormal distribution of hearth temperature, and adjusting a spatial air distribution strategy of the combustor. And after the correction coefficient is subjected to multi-stage buffer smoothing, a fuel control instruction is output to an executing mechanism. And switching to steady state control after the boiler reaches the preset load. The method adapts to the characteristics of a power plant unit, so that the starting process is more stable, the damage to a heated surface and pollutant emission are reduced, and rapid grid connection is assisted.

A combustor includes a combustion liner that defines a combustion chamber and an outer sleeve spaced apart from the combustion liner, such that an annulus is defined between the combustion liner and the outer sleeve. The combustor further includes a fuel injection assembly having a boss coupled to at least one of the combustion liner and the outer sleeve. The boss includes an inner flange coupled to the combustion liner, an outer flange, and a body extending between the outer flange and the inner flange. The boss defines a cooling circuit having a post-impingement plenum defined in the inner flange between an inner wall of the inner flange and an impingement plate in cooling proximity to the inner wall; and a plurality of film cooling channels that are defined in the inner flange and fluidly couple the post-impingement plenum to the combustion chamber.

The pulverized coal rotational flow stable combustion burner comprises a shell, a primary air pipe, a first swirler, a backflow cap and a laser generator assembly, a secondary air duct is defined between the primary air pipe and an air guide section, the first swirler is arranged in the secondary air duct, the backflow cap is arranged in the secondary air duct, and the laser generator assembly is arranged in the secondary air duct. The backflow cap is arranged in the combustion chamber and located at the outlet end of the primary air pipe. The laser generator assembly is used for emitting sheet-shaped laser beams into the combustion chamber so as to ignite pulverized coal in the combustion chamber. According to the invention, the size and the shape of the laser beam spot are adjusted, and the ignition efficiency and the stability in the pulverized coal combustion process are obviously improved by the aid of a cooling and combustion control strategy in which tertiary air and secondary air are matched; meanwhile, the laser power and mode can be flexibly switched, different coal quality and load working conditions can be adapted, the adaptability and combustion efficiency of the combustor are greatly improved, the service life of a hearth and related parts is prolonged, and the operation cost is reduced.

A combustor for a gas turbine (GT) system includes a combustor body including a non-additively manufactured (non-AM) part having corrosion at a first level and a replacement additively manufactured (AM) part coupled to the non-AM part. The replacement AM part has corrosion at a second level less than the first level. The replacement AM part includes at least an aft section of a tapered transition portion and an aft frame of the combustor body, and a plurality of shared parallel, sintered metal layers extending into the aft section of the tapered transition portion and the aft frame. The replacement AM part may also include a receiving element in a forwardmost end thereof configured to receive a rearwardmost remaining end of the non-AM part. The replacement AM part may also optionally include an AFS injector mount and part of a cylindrical portion of a combustion liner.

The invention discloses an optimized combustion control method and system for a combustor, and the method comprises the steps: obtaining a real-time combustion state parameter, and evaluating the real-time combustion state parameter based on a plurality of combustion evaluation indexes to obtain a real-time combustion evaluation value; when the real-time combustion evaluation value is smaller than the standard combustion evaluation value, a preset control model is determined according to the combustion evaluation value difference in combination with the real-time operation working condition, and an initial control method of the combustor is obtained; performing control simulation based on an initial control method to obtain simulation change characteristics of each real-time combustion state parameter, and optimizing corresponding control parameters in the initial control method according to the simulation change characteristics to obtain an optimized control method; by continuously optimizing and adjusting the control parameters of the combustor, the control efficiency and control precision of the combustor are improved, and efficient and stable operation of the combustor is achieved.

A gas turbine engine for an aircraft includes a fan and a turbo-engine having a combustor that combusts compressed air and fuel to generate combustion gases and a power turbine coupled to a shaft for driving the fan. The gas turbine engine includes a direct contact condenser for condensing steam in a first flow into liquid water droplets and to generate a second flow including the liquid water droplets, a water tank for collecting the liquid water droplets of the second flow, and a water pump for introducing the liquid water droplets from the water tank into the direct contact condenser to act as condensation nuclei for the steam in the first flow. The first flow is an exhaust-vapor flow extracted from the combustion gases and the second flow is an exhaust-condensate flow from the direct contact condenser.

A micro gas turbine engine may include a single-piece rotor having a compressor, a turbine, and a shaft manufactured from an additive manufacturing process. The compressor, turbine, and shaft are a single uniform piece and not separately joined together. The micro gas turbine engine may further include a ceramic cover having built in fuel injectors and stator blades for the compressor. The micro gas turbine engine may further include a inner combustor lining having built in stator blades for the turbine.

Described herein are methods and systems for non-contact boring of tunnels, trenches, and / or vertical shafts. A system comprises a chassis, a non-contact boring element, and a boring actuator connecting the non-contact boring element to the chassis and configured to position the non-contact boring element relative to the bore face. These three elements may form an internal subsystem as this subsystem within a tunnel, trench, or shaft. In some examples, a system further comprises an external subsystem, which is positioned away from the tunnel, trench, or shaft. The external subsystem is connected to the internal subsystem using an umbilical cord (e.g., providing power and control signals to the internal subsystem). Furthermore, the system may include an ejecta removal subsystem operationally coupled to the internal and external subsystems. Some examples of a non-contact boring element include a combustor (e.g., a jet turbine, a flame jet) and a plasma torch.