Wyniki wyszukiwania - BazTech

1

The analysis of the stability of the Cauchy problem in the cylindrical double-layer area

Ciałkowski Michał, Joachimiak Magda, Mierzwiczak Magdalena, Frąckowiak Andrzej, Olejnik Aleksander, Kozakiewicz Adam

Archives of Thermodynamics

|

2023

|

Vol. 44, no 4

563--579

EN

Ceramic protective coats, for instance, on turbine blades, create a double-layer area with various thermophysical properties and they require metal temperature control. In this paper, it is implemented by formulating a Cauchy problem for the equation of thermal conductivity in the metal cylindrical area with a ceramic layer. Due to the ill posed problem, a regularization method was applied consisting in the notation of thermal balance for the ceramic layer. A spectral radius for the equation matrix was taken as the stability measure of the Cauchy problem. Numerical calculations were performed for a varied thickness of the ceramic layer, with consideration of the non-linear thermophysical properties of steel and a ceramic layer (zirconium dioxide). A polynomial was determined which approximates temperature distribution in time for the protective layer. The stability of solutions was compared for undisturbed and disturbed temperature values, and thermophysical parameters with various ceramic layer thickness. The obtained calculation results confirmed the effectiveness of the proposed regularization method in obtaining stable solutions at random data disturbance.

2

Responsive Space Assets for Polish Armed Forces: Feasibility Study

Kiszkowiak Łukasz, Olejnik Aleksander, Rogólski Robert, Walkowiak Marcin, Zalewski Piotr

Safety & Defense

|

2022

|

1

30--40

EN

This study proposes an alternative (i.e., air-assisted) system for launching payloads (micro-satellites) into space using rockets fired from Su-22 or MiG-29 combat aircraft . This paper verifies and evaluates such an air-assisted rocket system used for launching payloads to low Earth orbit (LEO) in many aspects. Mission profile and rocket drop maneuver concepts have been developed. From the adopted model of calculations and simulation results, it follows that in the considered configuration, the aforementioned aircraft will be capable of accomplishing a mission in which a payload of at least 10 kg is launched into low Earth orbit. The analyses were complemented by simulations and wind tunnel tests verifying the impact that space rockets may exert on the aerodynamic and mechanical properties of the carrier aircraft . Results of numerical simulations and wind tunnel tests to which models of the air-assisted rocket launching system were subjected indicate the rocket’s impact on the aerodynamic characteristics of the aircraft and its in-flight properties is negligible. Similarly, load and strength tests to which the airframe’s load-bearing structures have been subjected also failed to show any significant changes or deformations caused by the space rockets attached. The kits proposed may be deemed as the so-called Responsive Space Assets for the Polish Armed Forces. Implementation of such a system not only offers independence from countries or commercial companies providing space services but also allows us to master new capabilities in the context of deploying satellite systems for safety and defense purposes.

3

Exhaust emissions of jet engines powered by biofuel

Merkisz Jerzy, Jasiński Remigiusz, Łęgowik Anna, Olejnik Aleksander

Transport Problems

|

2021

|

T. 16, z. 4

199--206

EN

Biofuel use is one of the basic strategies to reduce the negative impact of aviation on the environment. Over the past two decades, a number of biofuels produced from plants, lubricants and maintenance products have been developed and introduced. New fuels must have specific physicochemical parameters and meet stringent standards. his article presents a comparative analysis of the exhaust emissions measurement results from jet engines powered by traditional aviation kerosene and its blends with ATJ (Alcohol to Jet) biofuel. The concentrations of carbon dioxide, carbon monoxide and hydrocarbons were measured. Measurements were conducted in laboratory conditions for various engine load values. Based on the analysis, it was found that the use of biofuel increases the concentration of carbon monoxide and hydrocarbons in the exhaust gas relative to aviation kerosene. The use of biofuel did not result in an increase in fuel consumption and related carbon dioxide emissions. Based on the conducted research, it was found that biofuel use did not affect the ecological properties of the engine significantly. In addition, a correlation analysis of the measurement results from both engines was carried out.

4

Su-22 and MiG-29 aircraft as air-launch platforms for space rockets

Olejnik Aleksander, Zalewski Piotr

Biuletyn Wojskowej Akademii Technicznej

|

2020

|

Vol. 69, nr 3

89--103

EN

The work is an announcement on the current state of the research project implementation. The study presents the results of an analysis of the project’s research area. On this basis, the two-stage micro-satellite launch system was selected. The system, a space-kit is based on an adopted combat aircraft carrying a satellite-laden rocket that is fired at the maximum altitude. As a potential transport platform, two withdrawn supersonic aircraft were selected: the MiG-29 and the Su-22. A dedicated mission-laden rocket is to be carried under the fuselage. Preliminary analyses have shown that the aircraft indicated with the proposed mission profile will successfully carry out the task of launching a hypothetical rocket with a payload of at least 10 kg into low earth orbit. This confirmed the merits of the basic thesis of the research project. For the analysis of the aeromechanical properties of the kit, both 3D digital models for computer simulations and physical models scaled for tunnel tests were developed. Laser scanners were used to map aircraft geometry, and measurements were made on Su-22 and MiG-29 aircraft in the aviation laboratory of the Military University of Technology. Using three-dimensional scaled models generated in a CAD environment, physical solid models were printed for wind tunnel investigations. Preliminary computer simulations conducted in the ANSYS Fluent system did not point out any negative impact of the rocket on aerodynamic characteristics and stability of the both carrier aircraft.

PL

Praca jest komunikatem dotyczącym stanu realizacji projektu badawczego. W opracowaniu zaprezentowano wyniki analizy obszaru badawczego projektu. Na tej podstawie dokonano wyboru platformy-nosiciela rakiety kosmicznej. Dwustopniowy system do wynoszenia mikrosatelity bazuje na zaadaptowanym samolocie bojowym przenoszącym rakietę z ładunkiem satelitarnym, która odstrzeliwana jest na maksymalnie osiąganej wysokości. Jako potencjalną platformę transportową wytypowano dwa wycofywane ze służby bojowe samoloty naddźwiękowe: MiG-29 oraz Su-22. Wybrana rakieta z ładunkiem misyjnym ma być przenoszona pod kadłubem. Wstępne analizy wykazały, że wskazane samoloty przy zaproponowanym profilu misji z powodzeniem wykonają zadanie wyniesienia hipotetycznej rakiety z ładunkiem użytecznym o masie co najmniej 10 kg na niską orbitę okołoziemską. Potwierdziło to zasadność podstawowej tezy projektu badawczego. Dla potrzeb analizy własności aeromechanicznych zestawu opracowano zarówno modele cyfrowe 3D do symulacji komputerowych, jak i fizyczne modele skalowane do badań tunelowych. Do odwzorowania geometrii samolotów wykorzystano skanery laserowe, a pomiary wykonano na egzemplarzach samolotów Su-22 oraz MiG-29 znajdujących się w zasobach bazy laboratoryjnej Instytutu Techniki Lotniczej WML WAT. Wykorzystując trójwymiarowe modele skalowane wygenerowane w środowisku CAD, wydrukowano fizyczne modele bryłowe do badań w tunelu aerodynamicznym. Wstępne symulacje komputerowe przeprowadzone w systemie ANSYS Fluent nie wykazały negatywnego wpływu rakiety kosmicznej na charakterystyki aerodynamiczne i stateczność samolotu-nosiciela.

5

Działalność dydaktyczno-naukowa Instytutu Techniki Lotniczej Wydziału Mechatroniki i Lotnictwa WAT dla potrzeb lotnictwa

Olejnik Aleksander, Kachel Stanisław, Henzel Maciej, Zalewski Piotr

Przegląd Komunikacyjny

|

2019

|

R. 74, nr 1

8--13

PL

Wojskowa Akademia Techniczna im. Jarosława Dąbrowskiego w Warszawie jest wojskową, publiczną uczelnią akademicką kształcącą od ponad 60. lat inżynierów oraz prowadzącą działalność badawczo-naukową dla potrzeb Sił Zbrojnych RP i gospodarki narodowej. Działalność dla potrzeb lotnictwa prowadzi w Wydziale Mechatroniki i Lotnictwa Instytut Techniki Lotniczej, który jest kontynuatorem działalności zapoczątkowanej w 1951 roku przez Fakultet Lotniczy WAT. Fakultet ten został powołany dla potrzeb kształcenia inżynierów lotnictwa mogących eksploatować ówczesne samoloty o napędzie odrzutowym. Obecnie kształcenie lotnicze prowadzone jest w Wydziale na kierunku lotnictwo i kosmonautyka. W zakresie działalności naukowo-badawczej, instytut ma znaczące osiągnięcia krajowe i zagraniczne m.in. w zakresie eksperymentalnych oraz numerycznych badań aerodynamicznych statków powietrznych i struktur lotniczych, wyznaczania właściwości termofizycznych materiałów, jak również w zakresie systemów awionicznych i uzbrojenia lotniczego. W Instytucie działa także certyfikowany ośrodek szkolenia lotniczego personelu technicznego zgodnie z wymaganiami EASA Part-147 w oparciu o certyfikat nadany przez Urząd Lotnictwa Cywilnego.

EN

Military University of Technology in Warsaw (MUT) is a military, engineering university operating over 60 years (since 1951). MUT educates students as well as cadets and conducts scientific researches for the needs of the Polish Armed Forces and national economy as well as defence sector. The Institute of Aviation Technology of the Faculty of Mechatronics and Aerospace is a part of Military University of Technology and conducts activities for the military and aviation industry. The Institute is a successor of the former Faculty of Aviation, which was founded in 1951. The Faculty was established for the training of the military aviation engineers who could maintain the jet-engine aircraft, entered the service in 60. of the previous century. Recently, the Faculty provides the higher education in the field of Aerospace Engineering for both military (cadets) and civil students. The scientifi c and research activities of the Institute are focused on numerical aerodynamic as well as tunnel investigations, airframe structure strength simulation, determination of thermophysical properties of aviation materials, and on-board avionics systems as well aviation armament. Integrated part of the Institute is the Training Centre of aviation maintenance personnel, certifi ed with EASA Part-147 requirements. and it base on a certifi cate issued by the Civil Aviation Authority.