Academic literature on the topic 'Unsteady flow (Aerodynamics) Equations of state. Aerodynamics, Supersonic'
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Journal articles on the topic "Unsteady flow (Aerodynamics) Equations of state. Aerodynamics, Supersonic"
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Fazilati, Jamshid, Vahid Khalafi, and Hossein Shahverdi. "Three-dimensional aero-thermo-elasticity analysis of functionally graded cylindrical shell panels." Proceedings of the Institution of Mechanical Engineers, Part G: Journal of Aerospace Engineering 233, no. 5 (March 19, 2018): 1715–27. http://dx.doi.org/10.1177/0954410018763861.
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In the present paper, the aero-thermo-elastic behavior of a finite (three-dimensional) cylindrical curved panel geometry made from functionally graded material under high supersonic airflow is investigated. A generalized differential quadrature formulation is adopted while a steady-state through-the-thickness thermal field is also assumed. The geometry curvature and structural nonlinearity effects are included based on von Karman–Donnell strain–displacement relations. The nonlinear piston theory of third order is utilized in order to predict the unsteady aerodynamics loads induced from surrounding supersonic air stream. The functionally graded material is considered with temperature-dependent properties distributed in the thickness according to a power law function. Derived from the equilibrium equations, the aero-thermo-elastic governing equations are reduced to number of ordinary differential equations through using of the generalized differential quadrature method where the structure response is derived using fourth-order Runge–Kutta technique. The contribution of some parameters including flow Mach number, flow dynamic pressure, thickness temperature gradient, and functionally graded material volume fraction index on the flutter response as well as route-to-chaos behavior are reviewed. The calculated results are compared with those available in the literature wherever available and the accuracy and quality of the adopted generalized differential quadrature formulation in analyzing the aero-thermo-elastic behavior of three-dimensional functionally graded curved panels is shown. It reveals that using a three-dimensional approach, if any of Mach number and panel’s upper surface temperature is increased, the route-to-chaos behavior is reached through quasi-periodic motions.
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Lei, Wei Dong, Guo Cai Hu, and Quan Liu. "State-Space Model and Simulation for Dynamic Stall." Advanced Materials Research 989-994 (July 2014): 2258–63. http://dx.doi.org/10.4028/www.scientific.net/amr.989-994.2258.
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Because of the complexity of the progress of dynamic stall, the characteristic of dynamic stall of airfoil is always the difficulty of aerodynamics. A time-domain model has been formulated to represent the unsteady lift and pitching moment characteristics of a two-dimensional airfoil undergoing attached-flow conditions in a compressible flow and dynamic stall. The model is given as a set of first order differential state equations. The Beddoes-Leishman model was presented through modeling the effects of attached flow, separated flow and dynamic stall in the paper. A modified method is presented which includes a new stall-onset criterion and improves the position and separation conditions of the leading edge vortex, so that the B-L model is adaptive for lower Mach numbers. Then, the normal force and pitching moment on NACA0012 airfoil was calculated and compared with available experimental data to validate the reliability of the model.
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Chughtai, F. A., J. Masud, and S. Akhtar. "Unsteady aerodynamics computation and investigation of magnus effect on computed trajectory of spinning projectile from subsonic to supersonic speeds." Aeronautical Journal 123, no. 1264 (June 2019): 863–89. http://dx.doi.org/10.1017/aer.2019.32.
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AbstractThis paper describes the extensive numerical investigation carried out on a 203-mm spin-stabilised projectile to study the effects of Magnus force at high angles of attack on the stability and flight-trajectory parameters, for further validation and incorporation in a 6-DOF trajectory solver for flight-stability analysis. Magnus force typically influences the course of flight by causing the projectile to drift from its intended path in addition to generation of inbuilt dynamic instabilities in pitch and yaw orientation and is a function of AoA and spin rate. This study is a consolidation of the authors’ previous research on the same caliber projectile but with time-accurate analysis. It has been found that typically, the Magnus force and moment calculation requires time-accurate Navier Stokes equations to be solved numerically for accurate prediction(1,2). Hence, to complete the extraction of static and dynamic coefficients derivatives, unstructured time-accurate CFD analysis on multiple configurations, ranging from subsonic to supersonic Mach regimes, has been evaluated using Large Eddy Simulation (LES) and found to be suitable for capturing the desired effects. However, the LES simulation requires non-dimensional wall distance (y+) of the order of 0.5 – 1, with LES_IQ > 75% thus, is computationally-intensive. In addition, to cover the entire flight envelope from Charge 1 (249 m/s) to Charge 7 (595 m/s), at spin rate from 500 rad/s to 750 rad/s, 30 cases have been evaluated to generate the time-accurate coefficient library for integration with 6-DOF solver analysis. The results obtained have been compared with the available experimental data and found to be in reasonable agreement. The results of 6-DOF solver, incorporating the extracted coefficients, were compared with firing-table results, which further validated the computational methodology. This study provides an insight on how opposite flow interacts with the attached boundary layer due to spin rate and generates a turbulent interacting flow with variation in vortical structures for Q-Criterion vortex-flow visualization.
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Freskos, G., and O. Penanhoat. "Numerical Simulation of the Flow Field Around Supersonic Air-Intakes." Journal of Engineering for Gas Turbines and Power 116, no. 1 (January 1, 1994): 116–23. http://dx.doi.org/10.1115/1.2906780.
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The demand for efficiency in today’s and in future civil aircraft is such that experimental studies alone do not suffice to optimize aircraft aerodynamics. In this context, much effort has been spent in the past decade to develop numerical methods capable of reproducing the phenomena that occur in the engine flow field. This paper presents some studies in Computational Fluid Dynamics related to supersonic inlets. Two approaches are considered. First, there is a need for a code capable of calculating in a cost-efficient way the entire flow field around a two-dimensional or three-dimensional inlet, e.g., to perform parametric studies. To this effect, a computing method based on grid construction by mesh generator dedicated to inlet shapes and on the discretization of the unsteady Euler equations with an explicit upwind scheme was developed. The treatment of complex geometries led us to adopt a multiblock grid approach. Therefore particular attention was paid to the treatment of the boundary conditions between the different domains. Second, there is a need for a code that can capture local phenomena in order to get a better understanding of inlet behavior (shock/shock, shock/boundary layer interactions, etc.). To this effect a two-dimensional turbulent Navier-Stokes code is used. The two-equation k-ε turbulence model included in the program seems to be one of the most successful models for calculating flow realistically. Correction of the near-wall influence extends its capability to complex flow configurations, e.g., those with separated zones.
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de Andrade, Donizeti, and David A. Peters. "Coupling of a State-Space Inflow to Nonlinear Blade Equations and Extraction of Generalized Aerodynamic Force Mode Shapes." Applied Mechanics Reviews 46, no. 11S (November 1, 1993): S295—S304. http://dx.doi.org/10.1115/1.3122648.
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The aeroelastic stability of helicopter rotors in hovering flight has been investigated by a set of generalized dynamic wake equations and hybrid equations of motion for an elastic blade cantilevered in bending and having a torsional root spring to model pitch-link flexibility. The generalized dynamic wake model employed is based on an induced flow distribution expanded in a set of harmonic and radial shape functions, including undetermined time dependent coefficients as aerodynamic states. The flow is described by a system of first-order, ordinary differential equations in time, for which the pressure distribution at the rotor disk is expressed as a summation of the discrete loadings on each blade, accounting simultaneously for a finite number of blades and overall rotor effects. The present methodology leads to a standard eigenanalysis for the associated dynamics, for which the partitioned coefficient matrices depend on the numerical solution of the blade equilibrium and inflow steady-state equations. Numerical results for a two-bladed, stiff-inplane hingeless rotor with torsionally soft blades show the importance of unsteady, three-dimensional aerodynamics in predicting associated generalized aerodynamic force mode shapes.
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ABBAS, LAITH K., Q. CHEN, P. MARZOCCA, K. O'DONNELL, and D. VALENTINE. "AEROELASTIC BEHAVIOR OF LIFTING SURFACES WITH FREE-PLAY, AND AERODYNAMIC STIFFNESS AND DAMPING NONLINEARITIES." International Journal of Bifurcation and Chaos 18, no. 04 (April 2008): 1101–26. http://dx.doi.org/10.1142/s0218127408020860.
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Aeroelastic instabilities are dangerous phenomena, where aerodynamic load interacting with the inertia and elastic structural loads can induce catastrophic failures. In this paper the effects of aerodynamic nonlinearities as well as coupled plunging/pitching structural concentrated cubic type and freeplay nonlinearities in the dynamic of a two-dimensional double-wedge airfoil immersed in supersonic/hypersonic flow has been examined. The unsteady nonlinear aerodynamic force and moment on the airfoil are evaluated using the Piston Theory Aerodynamics modified to take into account the effect of the airfoil thickness. The resulting aeroelastic equations are numerically integrated to obtain time responses and to investigate the dynamic instability of the lifting surface under various initial displacement conditions. Results of the complex nonlinear aeroelastic system are presented in the form of bifurcation diagrams constructed from the response amplitude for various types of the system nonlinearity. It is shown that there exist regions, in which the system exhibit Limit Cycle Oscillations (LCOs), strongly dependent on the initial conditions of the aeroelastic system. Concentrated structural nonlinearities, that are freeplays and cubic type nonlinearities, can have significant effects on the flutter behavior and can cause large amplitude oscillations at lower airspeeds than for a linear system. It is also shown that larger amplitude LCOs occur when a pitching freeplay is considered, as compared with the case when a plunging freeplay is taken into account.
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Berci, Marco, and Rauno Cavallaro. "A Hybrid Reduced-Order Model for the Aeroelastic Analysis of Flexible Subsonic Wings—A Parametric Assessment." Aerospace 5, no. 3 (July 17, 2018): 76. http://dx.doi.org/10.3390/aerospace5030076.
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A hybrid reduced-order model for the aeroelastic analysis of flexible subsonic wings with arbitrary planform is presented within a generalised quasi-analytical formulation, where a slender beam is considered as the linear structural dynamics model. A modified strip theory is proposed for modelling the unsteady aerodynamics of the wing in incompressible flow, where thin aerofoil theory is corrected by a higher-fidelity model in order to account for three-dimensional effects on both distribution and deficiency of the sectional air load. Given a unit angle of attack, approximate expressions for the lift decay and build-up are then adopted within a linear framework, where the two effects are separately calculated and later combined. Finally, a modal approach is employed to write the generalised equations of motion in state-space form. Numerical results were obtained and critically discussed for the aeroelastic stability analysis of a uniform rectangular wing, with respect to the relevant aerodynamic and structural parameters. The proposed hybrid model provides sound theoretical insights and is well suited as an efficient parametric reduced-order aeroelastic tool for the preliminary multidisciplinary design and optimisation of flexible wings in the subsonic regime.
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Sayma, A. I., C. Bre´ard, M. Vahdati, and M. Imregun. "Aeroelasticity Analysis of Air-Riding Seals for Aero-Engine Applications." Journal of Tribology 124, no. 3 (May 31, 2002): 607–16. http://dx.doi.org/10.1115/1.1467086.
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This paper presents the results of a feasibility study on air-riding seal aeroelasticity for large-diameter aero-engines. A literature survey of previous seal studies revealed a significant amount of experimental work but numerical modeling using CFD techniques was relatively scarce. Indeed, most existing theoretical studies either deal with the structural behavior, or use simplified flow modeling. The aeroelasticity stability of a simplified air-riding seal geometry, devised for this particular feasibility study, was analyzed in three dimensions for typical engine operating conditions. Both the unsteady flow and structural vibration aspects were considered in the investigation. The boundary conditions and the seal gap were varied to explore the capabilities and limitations of a state-of-the-art unsteady flow and aeroelasticity code. The methodology was based on integrating the fluid and structural domains in a time-accurate fashion by exchanging boundary condition information at each time step. The predicted characteristics, namely lift and flow leakage as a function of pressure and seal gap, were found to be in agreement with the expected behavior. Operating seal gaps were determined from the actual time histories of the seal motion under the effect of the aerodynamic and the restoring spring forces. Both stable and unstable cases were considered. It was concluded that, in principle, the existing numerical tools could be used for the flow and aeroelasticity analyses of hydrostatic seals. However, due to large Mach number variations, the solution convergence rate was relatively slow and it was recognized that a preconditioner was needed to handle seal flows. For small gaps of about 10 microns, typical of spiral groved seals, the flow has a high Knudsen number, indicating that the Navier-Stokes formulations may no longer be valid. Such cases require a totally different treatment for the modeling of steady and unsteady aerodynamics, either by modifying the transport parameters of the Navier-Stokes equations or by considering rarefied gas dynamics.
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Sina, S. A., T. Farsadi, and H. Haddadpour. "Aeroelastic Stability and Response of Composite Swept Wings in Subsonic Flow Using Indicial Aerodynamics." Journal of Vibration and Acoustics 135, no. 5 (June 18, 2013). http://dx.doi.org/10.1115/1.4023992.
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In this study, the aeroelastic stability and response of an aircraft swept composite wing in subsonic compressible flow are investigated. The composite wing was modeled as an anisotropic thin-walled composite beam with the circumferentially asymmetric stiffness structural configuration to establish proper coupling between bending and torsion. Also, the structural model consists of a number of nonclassical effects, such as transverse shear, material anisotropy, warping inhibition, nonuniform torsional model, and rotary inertia. The finite state form of the unsteady aerodynamic loads have been modeled based on the indicial aerodynamic theory and strip theory in the subsonic compressible flow. Novel Mach dependent exponential approximations of the indicial aerodynamic functions have been developed. The extended Galerkin’s method was used to construct the mass, stiffness, and damping matrices of the nonconservative aeroelastic system. Eigen analysis of the system was performed to obtain the aeroelastic instability (divergence and flutter) boundaries. Also, solving the equations of motion in the time domain leads to the aeroelastic response of wing in different flight speeds. The obtained results are compared with the available results in the literature, which reveals an excellent agreement. The numerical results obtained in this article seek to clarify the effects of geometrical and material couplings and flight Mach number on the aeroelastic instability and response of composite wings in subsonic compressible flow.
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Yadav, Rajesh, and Aslesha Bodavula. "Numerical investigation of the effect of triangular cavity on the unsteady aerodynamics of NACA 0012 at a low Reynolds number." Proceedings of the Institution of Mechanical Engineers, Part G: Journal of Aerospace Engineering, June 17, 2021, 095441002110270. http://dx.doi.org/10.1177/09544100211027042.
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Time accurate numerical simulations were conducted to investigate the effect of triangular cavities on the unsteady aerodynamic characteristics of NACA 0012 airfoil at a Reynolds number of 50,000. Right-angled triangular cavities are placed at 10%, 25% and 50% chord location on the suction and have depths of 0.025c and 0.05c, measured normal to the surface of the airfoil. The second-order accurate solution to the RANS equations is obtained using a pressure-based finite volume solver with a four-equation transition turbulence model, γ–Re θt, to model the effect of turbulence. The two-dimensional results suggest that the cavity of depth 0.025c at 10% chord improves the aerodynamic efficiency ( l/d ratio) by 52%, at an angle of attack of α = 8°, wherein the flow is steady. The shallower triangular cavity when placed at 25%c and 50%c enhances the l/d ratio by only 10% and 17%, respectively, in the steady-state regime of angles of attack between α = 6° and 10°. The deeper cavity also enhances the l/d ratio by up to 13%, 22% and 14% at angles of attack between α = 6° and 10°. Even in the unsteady vortex shedding regime, at α =12° and higher, significant improvements in the time-averaged l/d ratios are observed for both cavity depths. The improvements in l/d ratio in the steady-state, pre-stall regime are primarily because of drag reduction while in the post-stall, unsteady regime, the improvements are because of enhancements in time-averaged C l values. The current finding can thus be used to enhance the aerodynamic performance of MAVs and UAVs that fly at low Reynolds numbers.
Dissertations / Theses on the topic "Unsteady flow (Aerodynamics) Equations of state. Aerodynamics, Supersonic"
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Bundy, Christopher. "Effects of unsteady flow and real gas equations of state on high pressure ram accelerator operation /." Thesis, Connect to this title online; UW restricted, 2001. http://hdl.handle.net/1773/10008.
Full textBooks on the topic "Unsteady flow (Aerodynamics) Equations of state. Aerodynamics, Supersonic"
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Yates, E. Carson. Integral-equation methods in steady and unsteady subsonic, transonic and supersonic aerodynamics for interdisciplinary design. Hampton, Va: National Aeronautics and Space Administration, Langley Research Center, 1990.
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Center, Langley Research, ed. Integral-equation methods in steady and unsteady subsonic, transonic and supersonic aerodynamics for interdisciplinary design. Hampton, Va: National Aeronautics and Space Administration, Langley Research Center, 1990.
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Center, Langley Research, ed. Integral-equation methods in steady and unsteady subsonic, transonic and supersonic aerodynamics for interdisciplinary design. Hampton, Va: National Aeronautics and Space Administration, Langley Research Center, 1990.
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Integral-equation methods in steady and unsteady subsonic, transonic and supersonic aerodynamics for interdisciplinary design. Hampton, Va: National Aeronautics and Space Administration, Langley Research Center, 1990.
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W, Swafford Timothy, Reddy T. S. R, and Lewis Research Center, eds. Euler flow predictions for an oscillating cascade using a high resolution wave-split scheme. [Cleveland, Ohio]: National Aeronautics and Space Administration, Lewis Research Center, 1991.
Find full textConference papers on the topic "Unsteady flow (Aerodynamics) Equations of state. Aerodynamics, Supersonic"
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Tokuyama, Yuki, Ken-ichi Funazaki, Hiromasa Kato, Noriyuki Shimiya, Mitsuru Shimagaki, and Masaharu Uchiumi. "Computational Analysis of Unsteady Flow in a Partial Admission Supersonic Turbine Stage." In ASME Turbo Expo 2014: Turbine Technical Conference and Exposition. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/gt2014-26071.
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Turbines used in upper stage engine for a rocket are sometimes designed as a supersonic turbine with partial admission. This study deals with numerical investigation of supersonic partial admission turbine in order to understand influences on the unsteady flow pattern, turbine losses and aerodynamic forces on rotor blades due to partial admission configuration. Two-dimensional CFD analysis is conducted using “Numerical Turbine” code. Its governing equation is URANS (Unsteady Reynolds Averaged Navier-Stokes Simulation) and fourth-order MUSCL TVD scheme is used for advection scheme. The unsteady simulation indicates that strongly non-uniform circumferential flow field is created due to the partial admission configuration and it especially becomes complex at 1st stage because of shock waves. Some very high or low flow velocity regions are created around the blockage sector. Nozzle exit flow is rapidly accelerated at the inlet of blockage sector and strong rotor LE shock waves are created. In contrast, at rotor blade passages and Stator2 blade passages existing behind the blockage sector, working gas almost stagnates. Large flow separations and flow mixings occur because of the partial admission configuration. As a result, additional strong dissipations are caused and the magnitude of entropy at the turbine exit is approximately 1.5 times higher than that of the full admission. Rotor1 blades experience strong unsteady aerodynamic force variations. The aerodynamic forces greatly vary when the Rotor1 blade passes through the blockage inlet region. The unsteady force in frequency domain indicates that many unsteady force components exist in wide frequency region and the blockage passing frequency component becomes pronounced in the circumferential direction force. Unsteady forces on Rotor2 blades are characterized by a low frequency fluctuation due to the blockage passing.
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Gerolymos, G. A. "Periodicity, Superposition, and 3D Effects in Supersonic Compressor Flutter Aerodynamics." In ASME 1988 International Gas Turbine and Aeroengine Congress and Exposition. American Society of Mechanical Engineers, 1988. http://dx.doi.org/10.1115/88-gt-136.
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In this work, a family of methods, both blade-to-blade surface and 3D, based on the numerical integration of the unsteady Euler equations, are used in studying various aspects of the unsteady aerodynamics of vibrating compressor cascades, in the supersonic flutter region. Most aerodynamic methods assume a traveling wave assembly mode of structural vibration, and suppose that the associated chorochronical periodicity is also encountered in the flowfield. This hypothesis has been tested by simulating the flow in a full annular cascade and has been verified in all the cases we have studied. When analyzing the aeroelastic stability of cascades, some assembly modal basis must be used. This, especially in presence of mistuning, relies on modal superposition hypotheses and linearity assumptions. The superposition assumption seems to be justified and the linear range of the amplitude-response is fairly large, although it varies greatly with frequency. Finally, an assessment of the importance of unsteady 3D effects is attempted using the 3D method.
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Freskos, G., and O. Penanhoat. "Numerical Simulation of the Flow Field Around Supersonic Air-Intakes." In ASME 1992 International Gas Turbine and Aeroengine Congress and Exposition. American Society of Mechanical Engineers, 1992. http://dx.doi.org/10.1115/92-gt-206.
Full textAbstract:
The demand for efficiency in today’s and in future civil aircraft is such that experimental studies alone do not suffice to optimize aircraft aerodynamics. In this context, much effort has been spent in the past decade to develop numerical methods capable of reproducing the phenomena that occur in the engine flow field. This paper presents some studies in Computational Fluid Dynamics related to supersonic inlets. Two approaches are considered. First, there is a need for code capable of calculating in a cost-efficient way the entire flow field around a 2D or 3D inlet, e.g. to perform parametric studies. To this effect, a computing method based on grid construction by mesh generator dedicated to inlet shapes and on the discretization of the unsteady Euler equations with an explicit upwind scheme was developed. The treatment of complex geometries led us to adopt a multiblock grid approach. Therefore particular attention was paid to the treatment of the boundary conditions between the different domains. Secondly, there is a need for code that can capture local phenomena in order to get a better understanding of inlet behaviour (shock/shock, shock/boundary layer interactions, etc.). To this effect a 2D turbulent Navier-Stokes code is used. The 2 equations k-ε turbulence model included in the program seems to be one of the most successful models for calculating flow realistically. Correction of the near-wall influence extends its capability to complex flow configurations, e.g. those with separated zones.
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Radulescu, Victorita. "Solution to Optimize the Airfoils Shapes Placed Into a Supersonic Viscous Flow." In ASME 2018 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/imece2018-86781.
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To improve the airfoils performances placed in supersonic flow is proposed a method of optimization for their shapes, in order to minimize the effect of the landing vortices. The theoretical modeling starts with the Navier-Stokes equations applied for thin layers, supplemented with additional conditions related to the profile shape. For a proper estimation of efficiency and responses at different flow regime’s conditions, were considered four aerodynamics airfoils, with different shapes and functioning characteristics. Two of them are special shapes of supersonic profiles and the other two deduced by theoretical assessments with an efficient behavior at high Reynolds numbers. The main purpose of this selection was to identify the essential aspects needed to be considered in numerical modeling of the airfoil’s wing shapes, as to assure an optimization of their behavior for different flow conditions. In the supersonic flow, the cross-sections of the wings are thin profiles, mainly symmetric, as to reduce the drag coefficient and to maximize, as possible, the lift coefficient. A supplementary method for the shape calculation of the aerodynamic profiles with small curvature, based on the Fredholm integral equation of the second kind, with a good behavior in the supersonic flow, is presented. Some aspects referring to unsteady flows and air compressibility are considered, as to simulate as much as possible the real, natural conditions. All profiles were tested, firstly, into a subsonic wind tunnel at incidences between 00 – 40 for different values of wind velocity, and secondly, into a supersonic wind tunnel, at the same incidences. The objective was to better understand and analyze the main factors, which influence the aerodynamic of shapes with curvature, and to assure an optimization of their behavior. The purpose of testing these profiles was to estimate a solution to improve the main characteristics, especially into the trailing and leading edges zones. There were also considered the effects of the attack angle, the influence of the wind velocity, air viscosity, and the shape’s curvature, on the vortices development. The obtained results allow a better functioning in supersonic flow regime, by eliminating the adverse pressure gradient and the boundary layer separation, assuring an optimum behavior especially into the leading edge zone.
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Li, Jing, and Robert E. Kielb. "Effects of Blade Count Ratio on Aerodynamic Forcing and Mode Excitability." In ASME Turbo Expo 2015: Turbine Technical Conference and Exposition. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/gt2015-43304.
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The effects of blade count ratio (BCR) on both the steady and unsteady blade loading and the sensitivity of generalized force to a change in mode shape (mode excitability) are studied numerically on two 2D configurations: a subsonic research compressor stage and a turbine stage with supersonic exit. Using the Harmonic Balance method, only a single passage is modeled to represent the actual blade count in a row at a high level of computational efficiency. BCR variation is achieved by scaling the downstream airfoils with a fixed chord-to-pitch ratio, thus preserving the steady-state aerodynamics. It is found that the interaction among potential-, wake-, and shock-related excitations, and the relative strength of harmonic contents are dependent on BCR, resulting in a non-monotonic correlation between unsteady loading and BCR in the downstream row. It is also found that the mode excitability can be sensitive to BCR variation in both up- and downstream rows in some cases. To the best of authors’ knowledge, this is the first work on BCR study involving supersonic flow and a discussion of mode excitability patterns.