Abstract: A Simulink modeling method for a mechanical hydraulic device of an aeroengine fuel regulator is proposed. The Simulink modeling method can implement high precision simulation of a mechanical hydraulic device of an engine fuel conditioning system, and greatly increase the simulation speed as compared with the existing modeling simulation in AMESim; solve the problem of a double-layered nested algebraic loop occurring when the mechanical hydraulic device is modeled in Simulink, and improve the simulation precision of the system. In addition, because of having certain universality, the resolving method for a double-layered nested algebraic loop can be generalized to resolve other types of algebraic loops. Meanwhile, the parameters of the simulation model provided by the present invention can be conveniently modified, and can provide a reference for modeling simulation of mechanical and hydraulic devices of engine fuel conditioning systems of other types.

Abstract: A Simulink modeling method for a mechanical hydraulic device of an aeroengine fuel regulator is proposed. The Simulink modeling method can implement high precision simulation of a mechanical hydraulic device of an engine fuel conditioning system, and greatly increase the simulation speed as compared with the existing modeling simulation in AMESim; solve the problem of a double-layered nested algebraic loop occurring when the mechanical hydraulic device is modeled in Simulink, and improve the simulation precision of the system. In addition, because of having certain universality, the resolving method for a double-layered nested algebraic loop can be generalized to resolve other types of algebraic loops. Meanwhile, the parameters of the simulation model provided by the present invention can be conveniently modified, and can provide a reference for modeling simulation of mechanical and hydraulic devices of engine fuel conditioning systems of other types.

Abstract: A stochastic configuration network based turbofan engine health parameter estimation method is disclosed. The stochastic configuration network based turbofan engine health parameter estimation method designed by the present invention combines the model based Kalman filter algorithm and the data-driven based stochastic configuration network, i.e. using the output of the stochastic configuration network as the compensation of the Kalman filter algorithm, so as to take into account the estimated result of the Kalman filter and the estimated result of the stochastic configuration network and improve the estimation accuracy of the original Kalman filter algorithm when the measurable parameters of the turbofan engine are less than the health parameters to be estimated. In addition, the present invention effectively reduces the accuracy loss caused by the poor structure of the neural network through the stochastic configuration network, and improves the generalization ability of the network.

Abstract: A design method for optimization of a transient control law of the aero-engine is disclosed, and performs the transient schedule optimization for the aero-engine by adopting an SQP algorithm, to realize the design of the transient control law along a constrained boundary condition. The fuel flow rate value is adjusted, other constraints remain unchanged, and the transient control law is designed under different limits. The transient time under each transient control law is calculated by constructing the transient time evaluation function. A lookuptable interpolation table is established by using the calculated transient time and corresponding fuel flow, to realize the fuel flow scheduling under different transient time. The fuel flow obtained by scheduling in the expected time is taken as an acceleration and deceleration control schedule of the closed-loop control of the aero-engine, and the output thereof is taken as the reference instruction of an acceleration process.

Abstract: The present invention belongs to the technical field of modeling and simulation of an aeroengine, and provides a method of modeling, simulation and fault injection for a combined high pressure gear pump for an aeroengine, which comprises: extracting the flow regions of a centrifugal pump and a gear pump in the aeroengine and merging into a combined flow region; dividing the combined flow region into different units according to a working principle; meshing each unit by a finite element analysis method, and setting boundary conditions and media parameters; simulating in Pumplinx to obtain the operation performance of the pumps, and adjusting the lateral clearance of the gear to debug the simulation model till a simulation error is within 5%; and then setting faults based on the debugged model to obtain the change of the operation performance of the pumps under the faults.

Abstract: A design method for optimization of a transient control law of the aero-engine is disclosed, and performs the transient schedule optimization for the aero-engine by adopting an SQP algorithm, to realize the design of the transient control law along a constrained boundary condition. The fuel flow rate value is adjusted, other constraints remain unchanged, and the transient control law is designed under different limits. The transient time under each transient control law is calculated by constructing the transient time evaluation function. A lookuptable interpolation table is established by using the calculated transient time and corresponding fuel flow, to realize the fuel flow scheduling under different transient time. The fuel flow obtained by scheduling in the expected time is taken as an acceleration and deceleration control schedule of the closed-loop control of the aero-engine, and the output thereof is taken as the reference instruction of an acceleration process.

Abstract: The present invention discloses a method for fault diagnosis of the sensors and actuators of an aero-engine based on LFT, and belongs to the field of fault diagnosis of aero-engines. The method comprises: establishing an aero-engine state space model using a combination of a small perturbation method and a linear fitting method; establishing an affine parameter-dependent linear-parameter-varying (LPV) model of the aero-engine based on the model; converting the LPV model of the aero-engine having perturbation signals and sensor and actuator fault signals into a linear fractional transformation (LFT) structure to obtain an synthesis framework of an LPV fault estimator; solving a set of linear matrix inequalities (LMIs) to obtain the solution conditions of the fault estimator; and designing the fault estimator in combination with the LFT structure to realize fault diagnosis of the sensors and actuators of an aero-engine.

Abstract: The present invention provides an interval error observer-based aircraft engine active fault tolerant control method, and belongs to the technical field of aircraft control. The method comprises: tracking the state and the output of a reference model of an aircraft engine through an error feedback controller; compensating a control system of the aircraft engine having a disturbance signal and actuator and sensor faults through a virtual sensor and a virtual actuator; observing an error between a system with fault of the aircraft engine and the reference model through an interval error observer, and feeding back the error to the error feedback controller; and finally, using a difference between the output of the reference model of the system with fault and the output of the virtual actuator as a control signal to realize active fault tolerant control of the aircraft engine.

Abstract: A system for generating an image of a region of interest (ROI) of a target object, the system including a camera, a target stage configured to receive the target object, the target stage configured to provide a translational movement and a rotational movement of the target object, and a controller. The controller is configured to control the camera and target stage to iteratively shift the target along scan trajectories of sample locations to capture images of each of a plurality of concentric rings and sub-rings of a predefined radial pitch over the ROI, the sample locations represented by polar coordinates defining sectors of each of the sub-rings. The controller is further configured to extract super resolution (SR) pixels from the images to reconstruct an SR image of each of the rings in the polar coordinates, and project the SR images into Cartesian coordinate images.

Abstract: A steady state and transition state multi-variable control method of a turbofan engine based on an active disturbance rejection control theory (ADRC) belongs to the technical field of aero-engine control. Firstly, multiple groups of manipulated variables and controlled variables of a turbofan engine are preliminarily selected, and then the manipulated variables and controlled variables with high correlation are further determined by a correlation analysis method. Each group of control instructions is planned as a tracking trajectory by using a tracking differentiator, and is used as the input of a nonlinear proportional-differential controller together with the current state estimated by the extended state observer to calculate the manipulated variables.

Abstract: An aero-engine full flight envelope model adaptive modification method based on a deep learning algorithm. A dynamic parallel compensator based on a recursive neural network is adopted to compensate the error of the original nonlinear model within the full flight envelope under the condition without aero-engine performance deterioration. A modifier based on a genetic algorithm is also adopted to conduct adaptive adjustment on correction coefficients of health parameters to be modified in the original nonlinear component-level model. The health parameters to be modified are determined by a multi-attribute decision algorithm based on integrated evaluation. The sum of the modified nonlinear component-level model output and the compensator output is consistent with the aero-engine operation test output data. This provides powerful support for the design of aero-engine control systems and fault diagnosis systems.

Abstract: A design method of aero-engine on-line optimization and multivariable control based on model prediction control realizes aero-engine multivariable control and on-line optimization according to thrust, rotational speed and other needs under the condition of meeting constraints. The first part is a prediction model acquisition layer that continuously establishes a small deviation linear model of an aero-engine near different steady state points based on the actual operating state of the aero-engine in each control cycle and external environment parameters and that supplies model parameters to a controller; and the second part is a control law decision-making layer which is a closed loop structure that consists of a model prediction controller and an external output feedback. The model prediction controller determines the output of the controller at next moment by solving a linear optimization problem according to an engine model in the current state, a control instruction and relevant constraints.

Abstract: The present invention belongs to the technical field of engine modeling, and provides a methodology for modeling a starting process of a micro gas turbine engine, comprising the following steps: modeling micro gas turbine engine speed; modeling a relationship between micro gas turbine engine performance parameters and speed; and performing error analysis. Since most existing micro gas turbine engine modeling methodologies are methodologies using pure mechanism or machine learning, it is difficult to accurately describe the starting process of a micro gas turbine engine, and machine learning requires a lot of test data. In engineering practice, pure mechanisms commonly used at present are complicated in operation, low in efficiency, and low in modeling accuracy. The invention provides a methodology for modeling a starting process of a micro gas turbine engine based on a combination of a mechanism and an identification method, which makes up for the deficiencies of the prior art.

Abstract: Described embodiments provide a method of generating an image of a region of interest of a target object. A plurality of concentric circular scan trajectories are determined to sample the region of interest. Each of the concentric circular scan trajectories have a radius incremented from an innermost concentric circular scan trajectory having a minimum radius to an outermost concentric circular scan trajectory having a maximum radius. A number of samples are determined for each of the concentric circular scan trajectories. A location of each sample is determined for each of the concentric circular scan trajectories. The locations of each sample are substantially uniformly distributed in a Cartesian coordinate system of the target object. The target object is iteratively rotated along each of the concentric circular scan trajectories and images are captured at the determined sample locations to generate a reconstructed image from the captured images.

Abstract: A system for generating an image of a region of interest (ROI) of a target object, the system including a camera, a target stage configured to receive the target object, the target stage configured to provide a translational movement and a rotational movement of the target object, and a controller. The controller is configured to control the camera and target stage to iteratively shift the target along scan trajectories of sample locations to capture images of each of a plurality of concentric rings and sub-rings of a predefined radial pitch over the ROI, the sample locations represented by polar coordinates defining sectors of each of the sub-rings. The controller is further configured to extract super resolution (SR) pixels from the images to reconstruct an SR image of each of the rings in the polar coordinates, and project the SR images into Cartesian coordinate images.

Abstract: Described embodiments provide a method of generating an image of a region of interest of a target object. A plurality of concentric circular scan trajectories are determined to sample the region of interest. Each of the concentric circular scan trajectories have a radius incremented from an inner-most concentric circular scan trajectory having a minimum radius to an outermost concentric circular scan trajectory having a maximum radius. A number of samples are determined for each of the concentric circular scan trajectories. A location of each sample is determined for each of the concentric circular scan trajectories. The locations of each sample are substantially uniformly distributed in a Cartesian coordinate system of the target object. The target object is iteratively rotated along each of the concentric circular scan trajectories and images are captured at the determined sample locations to generate a reconstructed image from the captured images.

Abstract: Soy-based high temperature products, or thermoset resins, are produced by solvent free polymerization of soy polyols and polyisocyanates at room temperature. The ratio of isocyanate equivalents to polyol equivalent used in the synthesis is greater than or equal to 3. The invented soy-based products are polyisocyanurate solid materials with excellent stability at high temperature. Heat resistance of the material is influenced by ratio of soy polyol and polyisocyanate.

Abstract: New methods of synthesizing new types of plant derived high molecular weight polyols are provided.

Abstract: Methods of one-pot synthesis of high molecular weight natural oil polyols having a functionality of between about 4 and about 8 are provided. The resultant polyols may be directly reacted with polyisocyanates to produce polyurethanes.

Abstract: A method of forming a stable mixture of a natural plant oil polyol and a petroleum-based polyol, including mixing a natural plant oil polyol with a monoglyceride, followed by adding a petroleum based polyol. Stabilized mixtures of plant oil and petroleum-based polyols can be used for synthesis of polyurethanes.