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Abstract

The measurement of lift and drag forces on the omithopter model with flapping wings was carried out in the wind tunnel. The wing movement had two degrees of freedom: flapping (around the longitudinal axis of the model) and feathering (around the wing axis). Forces were measured in static case - as averaged values during many cycles of movement, and in dynamic case - as unsteady forces captured in function of the flapping phase. The magnitudes of the aerodynamic coefficients of lift and drag were calculated.
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Authors and Affiliations

Jan Wojciechowski
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Abstract

First part of the article describes how we can by change of gating system achieve better homogeneity of product made by investment casting. Turbine engine flap was made by investment casting technology – lost wax casting. The casting process was realised in vacuum. The initial conditions (with critical occurrence of porosity) was simulated in ProCAST software. Numerical simulation can clarify during analysis of melt turbulent flow in gate system responsible for creation of entrained oxide films. After initial results and conclusions, the new gating system was created with subsequent turbulence analysis. The new design of gating system support direct flow of metal and a decrease of porosity values in observed areas was achieved. Samples taken from a casting produced with use of newly designed gating system was processed and prepared for metallography. The second part of article deals with identification of structural components in used alloy - Inconel 718. The Ni – base superalloys, which are combined unique physical and mechanical properties, are used in aircraft industry for production of aero engine most stressed parts, as are turbine blades.
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Authors and Affiliations

A. Remišová
J. Belan
A. Sládek
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Abstract

This paper presents the results of numerical analysis of aerodynamic characteristics of a sports car equipped with movable aerodynamic elements. The effects of size, shape, position, angle of inclination of the moving flaps on the aerodynamic downforce and aerodynamic drag forces acting on the vehicle were investigated. The calculations were performed with the help of the ANSYS-Fluent CFD software. The transient flow of incompressible fluid around the car body with moving flaps, with modeled turbulence (model Spalart-Allmaras or SAS), was simulated. The paper presents examples of effective flap configuration, and the example of configuration which does not generate aerodynamic downforce. One compares the change in the forces generated at different angles of flap opening, pressure distribution, and visualization of streamlines around the body. There are shown the physical reasons for the observed abnormal characteristics of some flap configurations. The results of calculations are presented in the form of pressure contours, pathlines, and force changes in the function of the angle of flap rotation. There is also presented estimated practical suitability of particular flap configurations for controlling the high-speed car stability and performance.

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Authors and Affiliations

Tomasz Janson
Janusz Piechna

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Abstract

Flap peening (FP) is a cold working technique used to apply a compressive force using small shots, this will lead to enhance the surface properties that it can sustain for long life during working conditions. In this study, several aircraft aluminum alloys materials namely; 2219 T6, 2024 T6, 7075T6, and 6061 T6 were flap peened under different rotational speeds. The effect of rotational speed on the average surface roughness (Ra) and average surface micro hardness have been investigated. As seen by the Scanning Electron Microscope SEM phots that the hardness of peened layer is increased. It was found that as the flap peening speeds increase the percent change in surface roughness (Ra) increases, and the percent change in surface micro hardness decreases. The maximum increase in Ra occurs in 2219 T80 and the minimum in 6061 T6 alloys, and for hardness, it is reported that the maximum occurs in 6061 T6 and the minimum in 2019 T80 alloy.
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Authors and Affiliations

Nabeel Abu Shaban
1
ORCID: ORCID
Nabeel Alshabatat
2
Safwan Al-Qawabah
1
ORCID: ORCID

  1. Al-Zaytoonah University of Jordan, Mechanical Engineering Department, Amman, Jordan
  2. Tafila Technical University, Mechanical Engineering Department, Tafila 66110, Jordan
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Abstract

With the steady increase in the incidence of breast cancer in women, treatment that includes not only tumor removal but also breast reconstruction is becoming a more relevant issue for oncologic and plastic surgeons. Mastectomy recently evolved as a form of primary prevention of hereditary breast cancer, commonly performed in combination with simultaneous reconstruction. A case of 44-year-old woman who underwent right mastectomy with adjuvant radiotherapy is presented. Due to the patient’s positivity for BRCA1 mutation and her wishes, a risk-reducing mastectomy with nipple-areola complex preservation and bilateral deep inferior epigastric artery perforator flap reconstruction were performed in one-stage. In selected cases this method appears to be the best possible procedure for simultaneous preventative and reconstructive management in patients with genetically determined breast cancer who have undergone mastectomy with radiotherapy.
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Authors and Affiliations

Łukasz Ulatowski
1
Piotr Gierej
1
Maria Molska
1

  1. Department of Plastic Surgery, Medical Centre for Postgraduate Education, Professor W. Orlowski Memorial Hospital, 231st Czerniakowska Street, 00-416 Warsaw, Poland

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