paulo soviero

Panel method formulation for oscillating airfoils in supersonic flow

AIAA Journal, Sep 1, 1995

The mathematical model for two-dimensional unsteady supersonic flow based on the reduced potentia... more The mathematical model for two-dimensional unsteady supersonic flow based on the reduced potential equation, also known as the hyperbolic Helmholtz equation, is presented and discussed. The purpose is to develop a rigorous formulation, in order to bring into light the correspondence between the supersonic and subsonic panel method theory. Source and doublet integrals are obtained, and Laplace transformation demonstrates that these are both solutions to the complete problem. It is shown that the doublet-only formulation reduces to a Volterra integrodifferential equation of the second kind, and a numerical method is proposed in order to solve it. To the authors' knowledge, this is the first reported solution to the unsteady supersonic thin airfoil problem through the use of doublet singularities. Comparisons with the source-only method are shown for the problem of a flat plate in harmonic heave. Results for the problems of a flat plate in harmonic pitch and under a sinusoidal gust are also presented. The doublet panel method was used to assess the importance of considering unsteady terms in the solution, as opposed to applying quasisteady formulations.

Analysis of compressible potential flow over aerofoils using the dual reciprocity method

Journal of the Royal Aeronautical Society, Apr 1, 2012

The use of the linearised potential model for the analysis of compressible flows is quite widespr... more The use of the linearised potential model for the analysis of compressible flows is quite widespread, and provides good results for subsonic and supersonic flows. However, the calculation of aerofoils and wings subject to transonic flows requires a non-linear model, such as the transonic small-disturbance (TSD) potential equation. The solution of the problem by a singularity distribution requires singularities over the field, as well as panels on the boundary, characterising the procedure known as field panel method. The present work shows results of calculations of the transonic small-disturbance potential equation for flows without shock waves using the dual reciprocity method (DRM), which permits calculation of integrals only at the boundary of the problem, without the need of field distributions. This approach, compared to the field panel methods, takes considerably less computer time, and shows a significant improvement when compared to results of linear theory without much additional computer time, making this technique adequate to design phases of aircraft. Pressure distribution results show good agreement with other methods found in litterature. The low computational cost of the present method allows us to perform parametric tests and explore the effects of thickness and Mach number on the lift and pitching moment coefficients. A discussion of the physical effect of these parameters on the problem is presented, and the thickness of the aerofoil is shown to increase the lift and change the position of the aerodynamic centre. However, this non-linear effect depends on the precise shape of the thickness distribution.

Avaliação Da Dependência Tecnológica Do Brasil, No Setor Aeroespacial, Com Vista Ao Desenvolvimento e À Segurança Do País

Revista da Escola Superior de Guerra, Dec 31, 1969

Download

Perda de Controle no Solo- Uma Análise pelo Programa SERA

ABSTRACT: Due to increasingly reliable aircraft technology, equipment and material failures have ... more ABSTRACT: Due to increasingly reliable aircraft technology, equipment and material failures have become rare. Today, aircraft accident causes are primarily attributed to the human link in the system. The ability to investigate, classify and detect the human factors that cause incidents and accidents is thus vital to prevent their recurrence and for designing the logic to help prevent their propagation. The goal of this work is to analyze an accident which took place in Brazil, which included at least one human factor as a probable cause, and with the respective investigation already concluded by the authority. For this purpose the SERA software is used as a tool to investigate, analyze, classify and to prevent recurrences.

Download

Sera e Hfacs: Dois Sistemas Para Análise e Classificação Do Erro Humano Em Acidentes e Incidentes Aeronáuticos

With the ever increasing reliability of aeronautical technology , failures that occur on account ... more With the ever increasing reliability of aeronautical technology , failures that occur on account of equipment or materials are getting increasingly rare, and the main causes of accidents, today, are attributable to the human being , according to the " National Transportation Safety Board " ( NTSB). Thus, the ability to investigate , classify and identify the human factors that are the root cause of accidents and incidents , plays a central role in the efforts to prevent recurrences, and is also important in the set-up of defenses in order to prevent the repetition and dissemination of “human errors”. It is observed that there is a trend nowadays in the use of organizational approach based models for the analysis and investigation of aeronautical accidents and incidents . The objective of this paper is to present a tool which allows the analysis and classification of such errors. Thus, it presents the SERA ( "Systematic Error and Risk Analysis" ) program, whose in...

Multidiciplinary Design Optimization for a Tailless Unmanned Aerial Vehicle with Electrical Propulsion Using the Weissinger L-Method as a Computional Tool to Obtain the Wing Aerodynamic Caracteristics

by Alejandro Rios, Saulo Barbosa Oliveira, and paulo soviero

Proceedings of the 23rd ABCM International Congress of Mechanical Engineering, 2015

Loss of Control on the Ground - An Analysis by SERA Software

by Simone Sobreda and paulo soviero

Aviation in Focus Journal of Aeronautical Sciences, 2013

Due to increasingly reliable aircraft technology, equipment and material failures have become rar... more Due to increasingly reliable aircraft technology, equipment and material failures have become rare. Today, aircraft accident causes are primarily attributed to the human link in the system. The ability to investigate, classify and detect the human factors that cause incidents and accidents is thus vital to prevent their recurrence and for designing the logic to help prevent their propagation. The goal of this work is to analyze an accident which took place in Brazil, which included at least one human factor as a probable cause, and with the respective investigation already concluded by the authority. For this purpose the SERA software is used as a tool to investigate, analyze, classify and to prevent recurrences.

Download

Loss of Control on the Ground - An Analysis by SERA Software

by Simone Sobreda and paulo soviero

Due to increasingly reliable aircraft technology, equipment and material failures have become rar... more Due to increasingly reliable aircraft technology, equipment and material failures have become rare. Today, aircraft accident causes are primarily attributed to the human link in the system. The ability to investigate, classify and detect the human factors that cause incidents and accidents is thus vital to prevent their recurrence and for designing the logic to help prevent their propagation. The goal of this work is to analyze an accident which took place in Brazil, which included at least one human factor as a probable cause, and with the respective investigation already concluded by the authority. For this purpose the SERA software is used as a tool to investigate, analyze, classify and to prevent recurrences. Perda de Controle no Solo - Uma Analise pelo Programa SERA RESUMO: Com o constante aumento da confiabilidade da tecnologia aeronautica, as falhas que ocorrem devido a equipamentos ou materiais sao cada vez mais raras e as principais causas de acidentes sao atribuiveis, hoje...

Download

Loss of Control on the Ground - An Analysis by SERA Software

Aviation in Focus Journal of Aeronautical Sciences, 2013

Due to increasingly reliable aircraft technology, equipment and material failures have become rar... more Due to increasingly reliable aircraft technology, equipment and material failures have become rare. Today, aircraft accident causes are primarily attributed to the human link in the system. The ability to investigate, classify and detect the human factors that cause incidents and accidents is thus vital to prevent their recurrence and for designing the logic to help prevent their propagation. The goal of this work is to analyze an accident which took place in Brazil, which included at least one human factor as a probable cause, and with the respective investigation already concluded by the authority. For this purpose the SERA software is used as a tool to investigate, analyze, classify and to prevent recurrences.

Download

Unsteady Aerodynamic Coefficients Obtained by a Compressible Vortex Lattice Method

Journal of Aircraft, May 22, 2012

Multidiciplinary Design Optimization for a Tailless Unmanned Aerial Vehicle with Electrical Propulsion Using the Weissinger L-Method as a Computional Tool to Obtain the Wing Aerodynamic Caracteristics

Proceedings of the 23rd ABCM International Congress of Mechanical Engineering, 2015

Jet inflow simulation and its downwash effect on lifting surfaces

Aeronautical Journal, 1991

Generalized vortex lattice method for oscillating lifting surfaces in planar supersonic flow

14th Applied Aerodynamics Conference, 1996

Analysis of Compressible Potential Flow Over Airfoils Using the Dual Reciprocity Method

25th AIAA Applied Aerodynamics Conference, 2007

A numerical model for thin airfoils in unsteady compressible arbitrary motion

Journal of the Brazilian Society of Mechanical Sciences and Engineering, 2007

A numerical method based on the vortex methodology is presented in order to obtain unsteady solut... more A numerical method based on the vortex methodology is presented in order to obtain unsteady solution of the aerodynamic coefficients of a thin airfoil in either compressible subsonic or supersonic flows. The numerical model is created through the profile discretization in uniform segments and the compressible flow vortex singularity is used. The results of the proposed model are presented as the lift and the pressure coefficient along the profile chord as a function of time. The indicial response for the unit step change of angle of attack and unit sharp-edged gust response of the profile are also obtained numerically. The results yielded by the present methodology are also compared with solutions available in the literature.

Download

Panel method formulation for oscillating airfoils in supersonic flow

12th Applied Aerodynamics Conference, 1994

Experimental results of a Mach 10 conical-flow derived waverider to 14-X hypersonic airspace vehicle

by paulo soviero and Antonio Carlos de Oliveira

Journal of Aerospace Technology and Management, 2011

The 14-X project objective is to develop a higher effi cient satellite launch alternative, using ... more The 14-X project objective is to develop a higher effi cient satellite launch alternative, using a Supersonic Combustion Ramjet (SCRAMJET) engine and waverider aerodynamics. For this development, the waverider technology is under investigation in Prof. Henry T. Nagamatsu Aerothermodynamics and Hypersonics Laboratory (LHTN), in IEAv/DCTA. The investigation has been conducted through ground test campaigns in Hypersonic Shock Tunnel T3. The 14-X Waverider Vehicle characteristic was verifi ed in shock tunnel T3 where surface static pressures and pitot pressure for Mach number 10 were measured and, using Schlieren photographs Diagnostic Method, it was possible to identify a leading-edge attached shock wave in 14-X lower surface.

Download

Panel Method Formulation for Oscillating Airfoils in Sonic Flow

Journal of the Brazilian Society of Mechanical Sciences, 2001

Unsteady Aerodynamic Coefficients Obtained by a Compressible Vortex Lattice Method

38th Fluid Dynamics Conference and Exhibit, 2008

Compressible Unsteady Vortex Lattice Method for Arbitrary Two-Dimensional Motion of Thin Profiles

Journal of Aircraft, 2007

Uploads

Papers by paulo soviero

Log In