A concept of monitoring for material properties with residual life estimation of rotor blades for gas turbine engines is proposed. The structure of on-board control and conditionmonitoring system based on the intelligent pyrometer module with the algorithm for calculating the residual life of turbine rotor blades is described.
Numerical modelling of fluid film break-up is carried out using adaptive mesh models. The results obtained are compared with experimental data. It is shown that using local adaptation with hanging nodes allows reaching a sufficient accuracy of fluid film boundaries estimation and definition of droplet dimensions resulted from its atomization. It is noticed that these are not only a turbulence model and adaptation sequence selection that substantially affect the computation results but also a type of initial mesh model.
The paper provides a method for multi-criteria selection of the optimal structural layout option based on a fuzzy logic inference that allows for uncertainties in engineering and operates with heterogeneous information of the qualitative and quantitative nature for the systems being designed.
For an interception strategy of a removable target by a return space vehicle (RSV), we propose a structure of the control law by the aerodynamic efficiency that determines a chain of the three standard trajectories: nosing-up–free flight–nosing-down. A solution of the terminal problem is to determine numerical values of the control parameters that define moments to switch the RSV flight from one standard trajectory to another.
The flow of viscous incompressible fluid in the lateral rotation cavity of centrifugal pump is considered. The finite-difference equations have been developed for numerical simulation of the flow in view of shear stresses in a spatial boundary layer that allow a disk resistance moment to be defined. The numerical results are presented.
A method is proposed that allows searching for the required helicopter control of the flight on a given trajectory in a three dimensional space based on the mathematical (simulation) model. An implementation algorithm is provided. An example of computing the helicopter flight trajectory is given for a steady level turn regime.
The paper reports the results of experimental studies and numerical calculations of the flame stabilization process in the model gas turbine combustor. The mathematical model of the process in the combustor is presented. Using this model, the main parameters of combustors with different ratios of total area of the holes in the combustion zone to total area of all holes, are determined.
The dependences of thermal and hydraulic characteristics of compact heat exchangers with coplanar channels on their geometrical parameters and cooling modes are presented. The given results of tests allow us to estimate the efficiency of the cooling system of heat exchangers with various parameters of ribbing.
Optimization of project-ballistic parameters of the spacecraft with propulsion systems with energy accumulation during the orbital transfer between low Earth orbits in the non-central gravitational field of the Earth is considered. The mass model of the spacecraft with an uncontrollable power-limited engine with the energy accumulator is used. The method of the project-ballistic optimization is obtained as an iterative procedure. Energy storage usage efficiency during the orbital transfer between low Earth orbits is estimated.
The paper deals with the technology of fabricating the filters used in aircraft engines. The new methods of electrochemical dimensional processing are presented, which are used for collective processing of openings with various cross-sections in thin-walled filters.
Some results of investigating the geometrical and jet impact on secondary flows and thermal state of cooled inter-profile end surfaces of gas turbine engine nozzles have been set forth under different secondary flows interaction degree in a blade channel.
This paper presents the regularities of effect of the input asymmetry of the velocity profile on the flow structure in a separated diffuser of the GTE annular combustion chamber. These regularities allow predicting the integral value of hydraulic resistance. We experimentally identified a kind of dependence between the hydraulic losses and Reynolds number in the case of asymmetric velocity profile in a prediffuser assessing the growth of pressure losses. Some updated dependencies are proposed that take into account the joint effect of the input parameters of the working fluid on the integral characteristics of its effectiveness.
The authors conducted a detailed study of possible options for geometry of blades with pressure and power characteristics of the impeller.
This paper deals with roughing milling of vane channels for axial blisks by a cup tool. The effect of the shaping strategy on waviness of the surfaces being machined and allowance for subsequent operations is determined.
The Mi-2 helicopter was taken as an example for modeling the main and tail rotors operation with account for the interference at low speed sliding flight. Aerodynamic characteristics were calculated. The form of nonlinear vortical wake was obtained.
In this paper, under consideration is the complex approach to analyzing the operation of a simulator for the hollow blade made from the VT6 titanium alloy. The stress state parameters in the hollow-monolithic part transition zone of the cantilevered simulator at bending under the distributed load are determined.
This paper considers the purpose, principles of construction, algorithms of generating output signals and the functional diagram of a simulator of aircraft air signals that is built based on the vortex sensor of aerodynamic angle and true airspeed.
Dynamics of a gas bubble in a liquid near a solid wall is studied. The influence of the initial spheroidal disturbances of the bubble shape and the distance to the wall on the dynamics of the bubble–liquid system is analyzed. The pressure in the bubble is initially greater than that of the surrounding liquid. An algorithm based on the Euler scheme and the boundary element method is applied in the calculations.
The paper describes the design concepts, a brief theory, and analysis of the power and metrological characteristics of the fiber-optical digital-to-analog converters as the elements of multiplexing the data from onboard position sensors in aircraft instruments and systems.
We discuss the use of multilayered annular-plate dampers as rotor supports in turbopumps of the RD-0120 and RD-0146 rocket engines. We present a technique of calculating the elastic and damping characteristics of multilayer corrugated annular supports in the case of the conical precession of the rotor.
