Continuous Integration Dashboard

Tato bakalářská práce se zabývá vývojem webové aplikace pro integraci nástrojů CI/CD. Úkolem bylo prostudovat dostupné technologie a připravit aplikaci odpovídající zadaným požadavkům. Během implementace systému byly nastudovány aspekty vývoje, jako jsou nástroje CI/CD, rámce serveru, uživatelské rámce, databáze, technologie webových serverů, nástroje pro práci s kontejnery. Výsledkem bakalářské práce je aplikace skládající se ze tří částí: serverová část, klientská část a databáze. Tato aplikace je rozdělená do tří částí a připravena ke spuštění v nástrojích kontejnerizace.This bachelor thesis deals with the development of a web application for integrating CI/CD instruments. The main goal was to study the currently available technologies and prepare an application corresponding to the provided requirements. During system implementation, were learned development aspects such as CI/CD instruments, server-side frameworks, client-side frameworks, databases, web server technologies, containerization tools. As a result of bachelor's thesis we prepared an application consisting of three parts: server part, client part and database. This application is prepared to run divided into three parts in containerization.

A modified dual time integration technique for aerodynamic quasi-static and dynamic stall hysteresis

open access articleSimulation of the aerodynamic stall phenomenon in both quasi-static and dynamic conditions requires expensive computational resources. The computations become even more costly for static stall hysteresis using an unsteady solver with very slow variation of angle of attack at low reduced frequencies. In an explicit time-marching solver that satisfies the low Courant number condition, that is, CFL<1, the computational cost for such simulations becomes prohibitive, especially at higher Reynolds numbers due to the presence of thin-stretched cells with large aspect ratio in the boundary layer. In this paper, a segregated solver method such as the Semi-Implicit Method for Pressure-Linked Equations (SIMPLE) is modified as a dual pseudo-time marching method so that the unsteady problem at each time step is reformulated as a steady state problem. The resulting system of equations in the discretized finite volume formulation is then reduced to zero or near-zero residuals using available convergence acceleration methods such as local time stepping, multi-grid acceleration and residual smoothing. The performance and accuracy of the implemented algorithm was tested for three different airfoils at low to moderate Reynolds numbers in both incompressible and compressible flow conditions covering both attached and separated flow regimes. The results obtained are in close agreement with the published experimental and computational results for both quasi-static and dynamic stall and have demonstrated significant savings in computational time

Reduction of energy losses on car movement while using a combined electromechanical drive of leading wheels

This article addresses the problem that fluctuations in the torque of an internal combustion engine (ICE) lead to additional energy losses, as it causes fluctuations in the speed and kinetic energy of the car. These losses increase as the frequency of oscillations of the torque of the internal combustion engine approaches the frequency of free (natural oscillations) of the running gear of the car in the longitudinal direction. If there is an elastic connection between the traction force and the movement of the car, the movement of the latter can be represented as complex. At the same time, the portable movement is uniform, and the relative movement is oscillatory. This article presents the results of the study of these losses for cars with mechanical and combined electromechanical drive wheels. Analytical expressions are obtained, which allows to take into account additional energy losses including the tangential rigidity of the tire and the rigidity of the suspension in the longitudinal direction. When using a combined electromechanical drive of the drive wheels as well as in the case of a mechanical transmission of a car, the resonance is dangerous. But with the increase in the share of torque kem on the wheel generated by the electric motor, the relative additional energy losses for the movement of the car are reduced

Computational Simulation of Airfoils Stall Aerodynamics at Low Reynolds Numbers

Experimental results for aerodynamic static hysteresis at stall conditions obtained in the TsAGI's T-124 low-turbulence wind tunnel for NACA0018 are presented and analysed. Computational predictions of aerodynamic static hysteresis are made using the OpenFOAM simulations considering di erent grids, turbulence models and solvers. Comparisons of compu- tational simulation results with experimental wind tunnel data are made for 2D NACA0018 and NACA0012 airfoils at low Reynolds numbers Re = (0.3-1.0) millions. The properties of the proposed phenomenological bifurca- tion model for simulation of aerodynamic loads at the existence of static hysteresis are discussed

Improvement of the method for assessing the energy load of vehicle

The aim of the research is to improve the indicators assessment accuracy of the vehicle energy load by improving the method of experimentally - theoretical determination of the aerodynamic drag parameters of vehicle in motion. To achieve this goal, it is necessary to solve the problem of determining the dependence of the energy load level on vehicle speed with varying frontal aerodynamic drag coefficient. Studies carried out to clarify the calculation of the parameters of vehicle aerodynamic drag in motion made it possible to determine the correlation between the actual effective engine capacity and the maximum kinetic energy of vehicle at translational motion. When determining the vehicle aerodynamic drag, the constant coefficient of aerodynamic drag is used depending on the speed in all range of vehicle speeds. This leads to significant mistakes in determining the necessary engine capacity expendable to overcome the aerodynamic drag, and vehicle fuel consumption. As a result of the research, analytical expressions, allowing to take into account additional energy losses and correlation between the kinetic energy of the vehicle steady motion and the effective engine capacity have been obtained. The theoretical contribution of the research is that the correlation coefficient between the kinetic energy of vehicle in motion and the effective engine capacity – have been proposed. Studies have shown that if speed of vehicle increases the indicator will monotonously decrease in the range of actual speeds

Computational Ground Effect Aerodynamics and Airplane Stability Analysis During Take-off and Landing

Computational simulations of aerodynamic characteristics of the Common Research Model (CRM), representing a typical transport airliner, are conducted using CFD methods in close proximity to the ground. The obtained dependencies on bank angle for aerodynamic forces and moments are further used in stability and controllability analysis of the lateral-directional aircraft motion. Essential changes in the lateral-directional modes in close proximity to the ground have been identified. For example, with approach to the ground, the roll subsidence and spiral eigenvalues are merging creating the oscillatory Roll-Spiral mode with quite significant frequency. This transformation of the lateral-directional dynamics in piloted simulation may affect the aircraft responses to external crosswind, modify handling quality characteristics and improve realism of crosswind landing

Computational Simulation of Airfoils Stall Aerodynamics at Low Reynolds Numbers

Experimental results for aerodynamic static hysteresis at stall conditions obtained in the TsAGI's T-124 low-turbulence wind tunnel for NACA0018 are presented and analysed. Computational predictions of aerodynamic static hysteresis are made using the OpenFOAM simulations considering di erent grids, turbulence models and solvers. Comparisons of compu- tational simulation results with experimental wind tunnel data are made for 2D NACA0018 and NACA0012 airfoils at low Reynolds numbers Re = (0.3-1.0) millions. The properties of the proposed phenomenological bifurca- tion model for simulation of aerodynamic loads at the existence of static hysteresis are discussed

Impact of Ground Effect on Airplane Lateral Directional Stability during Take-Off and Landing

Open Access journalComputational simulations of aerodynamic characteristics of the Common Research Model (CRM), representing a typical transport airliner are conducted using CFD methods in close proximity to the ground. The obtained dependencies on bank angle for aerodynamic forces and moments are further used in stability and controllability analysis of the lateral-directional aircraft motion. Essential changes in the lateral-directional modes in close proximity to the ground have been identified. For example, with approach to the ground, the roll subsidence and spiral eigenvalues are merging creating the oscillatory Roll-Spiral mode with quite significant frequency. This transformation of the lateral-directional dynamics in piloted simulation may affect the aircraft responses to external crosswind, modify handling quality characteristics and improve realism of crosswind landing. The material of this paper was presented at the Seventh European Conference for Aeronautics and Space Sciences EUCASS-2017. Further work is carried out for evaluation of the ground effect aerodynamics for a high-lift configuration based on a hybrid geometry of DLR F11 and NASA GTM models with fully deployed flaps and slats. Some aspects of grid generation for a high lift configuration using structured blocking approach are discussed

Prediction Of Static Aerodynamic Hysteresis On A Thin Airfoil Using OpenFOAM

The file attached to this record is the author's final peer reviewed version. The Publisher's final version can be found by following the DOI link.The paper presents computational prediction of aerodynamic hysteresis loops in static conditions for a two-dimensional aerofoil that was used as a cross-section profile for a rectangular wing with an aspect ratio of five, tested in the TsAGI T-106 wind tunnel at a Reynolds number of =6×106 and a Mach number of =0.15. Tests in the wind tunnel showed that minor changes in the curvature of the leading edge of the thin aerodynamic profile lead to a significant increase in the maximum lift coefficient when significant hysteresis loops appear in the aerodynamic characteristics of the wing. The computational predictions of stall aerodynamics presented in this paper are made for a two-dimensional profile using the OpenFOAM open-source code to simulate a flow based on the unsteady Reynolds-averaged Navier–Stokes equations using the Spalart–Allmaras turbulence model. The calculation results confirm the existence of loops of static aerodynamic hysteresis and bistable structures of the separated flow, and the results are qualitatively similar to the results observed experimentally on the wing with a finite aspect ratio