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Hybrid rocket engines are a green alternative to solid rocket motors and may represent a low-cost alternative to kerosene fueled rockets, while granting performance and control features similar to that of typical storable liquid rocket engines. In this work, the design of a three-stage hybrid launcher is optimized by means of a coupled procedure: an evolutionary algorithm optimizes the engine design, whereas an indirect optimization method optimizes the corresponding ascent trajectory. The trajectory integration also provides the vertical emission profiles required for the evaluation of the environmental impact of the launch. The propellants are a paraffin-based wax and liquid oxygen. The vehicle is launched from the ground and uses an electric turbo pump feed system. The initial mass is given (5000 kg) and the insertion of the payload into a 600-km circular, and polar orbit is considered as a reference mission. Clusters of similar hybrid rocket engines, with only few differences, are employed in all stages to reduce the development and operational costs of the launcher. Optimization is carried out with the aim of maximizing the payload mass and then minimizing the overall environmental impact of the launch. The results show that satisfactory performance is achievable also considering rocket polluting emissions: the carbon footprint of the launch can be reduced by one fourth at the cost of a 5-kg payload mass reduction.

Time Difference of Arrival (TDOA) networks could support spacecraft orbit determination or near-space (launcher and suborbital) vehicle tracking for an increased number of satellite launches and space missions in the near future. The evaluation of the geometry of TDOA networks could involve the dilution of precision (DOP), but this parameter is related to a single position of the target, while the positioning accuracy of the network with targets in the whole celestial vault should be evaluated. The paper presents the derivation of the MDOP (minimum dilution of precision), a parameter that can be used for evaluating the performance of TDOA networks for spacecraft tracking and orbit determination. The MDOP trend with respect to distance, number of stations and target altitude is reported in the paper, as well as examples of applications for network performance evaluation or time precision requirement definitions. The results show how an increase in the baseline enables the inclusion of more impactive improvements on the MDOP and the mean error than an increase in the number of stations. The target altitude is demonstrated as noninfluential for the MDOP trend, making the networks uniformly applicable to lower altitude (launchers and suborbital vehicles) and higher altitude (Low and Medium Earth Orbits satellites) spacecraft.

Sensor networks based on Impulse-Radio Ultra Wideband (IR-UWB) technology have gained traction in fields where precise localization and robust communication links are required. In spacecraft and launchers these networks can be used to connect sensors to a central on board computer or to provide a communication link between the different subsystems. This contributes to a reduced cable harness, a key driver in overall spacecraft mass and design complexity. This paper presents an application for a launcher mounted multi-camera system based on low power IR-UWB sensor nodes. In combination with a modified high-throughput MAC layer from the IEEE 802.15.4 standard it is able to provide an update rate of multiple frames per second, where traditional sensor network systems would need half a minute to deliver a single frame. In addition, it is not interfering with critical telecommand/telemetry radio links of the launch vehicle due to the nature of the wideband transmission.

Since many decades, Carbon/Carbon composites are used as structural parts in rocket engines due to their excellent thermomechanical properties. However, under highly oxidizing/corrosive atmosphere and high gas flow rates, carbon suffers from severe oxidation. To improve oxidation resistance of these composites, Ultra High Temperature Ceramics (UHTC) can be used as a protection. To protect the whole composite, the introduction of UHTC as a matrix has been done using a liquid phase process combining: (i) slurry infiltration process and (ii) reactive melt infiltration. Matrix constituents belong to the (B;C;Si;Zr) system. Material characterisation allowed a better understanding of the infiltration mechanisms and of the phase distribution and composition in respect to the processing conditions. To select the best composition, oxyacetylene torch testing has been done to recreate spacecraft launch environmental conditions. Post-test characterisation has been done to evaluate protection efficiency of each matrix composition for single use and possible reuse. Finally, advantages and drawbacks assessment of each composition allowed to highlight the most protective composition and phase distribution., Les composites de type Cf/C sont utilisés en tant que pièces structurales dans les propulseurs spatiaux du fait de leurs excellentes propriétés mécaniques dans le domaine des très hautes températures. Néanmoins, l’atmosphère oxydante et corrosive créée lors du décollage des lanceurs et les hauts flux gazeux dégradent ces matériaux. Afin d’améliorer les performances de ces matériaux vis-à-vis de l’oxydation/corrosion, une protection composée de céramiques ultra-réfractaires (dites UHTC) peut être appliquée. Pour une efficacité de protection optimale, des phases UHTC ont été introduites en tant que constituants de la matrice. Dans ces travaux de thèse, la matrice a été réalisée par l’intermédiaire d’un procédé d’élaboration en phase liquide combinant : (i) l’introduction de poudres et (ii) la densification par infiltration réactive d’un métal fondu. La composition de la matrice appartient au système (B;C;Si;Zr). La caractérisation des matériaux après élaboration a permis de comprendre les mécanismes d’infiltration et les réactions permettant de mieux contrôler la composition chimique et la répartition des phases. Des essais sous torche oxyacétylénique ont été utilisés pour se placer dans des conditions proches de l’application visée. La caractérisation post-test des matériaux a permis d’évaluer l’efficacité de la protection dans le cas d’une utilisation unique et également d’une possible réutilisation. Les résultats en oxydation/corrosion ont permis de classer les matériaux en fonction de leur efficacité de protection.

This work uses different finite element approaches to the free vibration analysis of reinforced shell structures, and a simplified model of a typical launcher with two boosters is used as an example. The results obtained using a refined one-dimensional (1D) beam model are compared to those obtained with commercial finite element software. The 1D models that are used in the present work are based on the Carrera Unified Formulation (CUF), which assumes a variable kinematic displacement field over the cross-sections of the beam. Two different sets of polynomials that correspond to Taylor (TE) or Lagrange (LE) expansions were used. The analyses focused on three reinforced structures: a stiffened panel, a reinforced cylinder and the complete structure of the launcher. The frequencies and natural modes obtained using one-dimensional models are compared to those obtained from classical finite element analysis. The classical FE models were built using a beam-shell or solid elements, and the results indicate that the refined beam models can in fact be used to investigate the behavior of very complex reinforced structures. These models can predict the shell-like modes that are typical of thin-walled structures that cannot be detected using classical beam models. The refined 1D models used in the present work provide results that are as accurate as those from solid FE models, but the 1D models have a much lower computational cost.

The objective of this paper is the investigation of the capability of operational modal analysis approaches to deal with time-varying system in the low-frequency domain. Specifically, the problem of the identification of the dynamic properties of a launch vehicle, working under actual operative conditions, is studied. Two OMA methods are considered: the frequency-domain decomposition and the Hilbert transform method. It is demonstrated that both OMA approaches allow the time-tracking of modal parameters, namely, natural frequencies, damping ratios, and mode shapes, from the response accelerations only recorded during actual flight tests of a launcher characterized by a large mass variation due to fuel burning typical of the first phase of the flight.

The purpose of this work is to simulate the flow at the exit of Vulcan 1 engine of European launcher Ariane 5. The geometry of the propellant nozzle is already determined using the characteristics method. The pressure in the outlet section of the nozzle is less than atmospheric pressure on the ground, causing the existence of oblique and normal shock waves at the exit. During the rise of the launcher, the atmospheric pressure decreases and the shock wave disappears. The code allows the capture of shock wave at exit of nozzle. The numerical technique uses the Flux Vector Splitting method of Van Leer to ensure convergence and avoid the calculation instabilities. The Courant, Friedrichs and Lewy coefficient (CFL) and mesh size level are selected to ensure the numerical convergence. The nonlinear partial derivative equations system which governs this flow is solved by an explicit unsteady numerical scheme by the finite volume method. The accuracy of the solution depends on the size of the mesh and also the step of time used in the discretized equations. We have chosen in this study the mesh that gives us a stationary solution with good accuracy., {"references":["Haoui, R., \"Design of the propelling nozzles for the launchers and satellites\", International Journal of Aeronautical and space Sciences, 15(1), 2014, pp91-96. DOI:10.5139/IJASS.2014.15.1.91.","Haoui, R. Gahmousse, A. Zeitoun, D., \"Condition of convergence applied to an axisymmetric reactive flow\", 16th CFM, n°738, Nice, France, 2003.","Goudjo, J.A. Désidéri, \"A finite volume scheme to resolution an axisymmetric Euler equations (Un schéma de volumes finis décentré pour la résolution des équations d'Euler en axisymétrique),\" Research report INRIA 1005, 1989.","Van Leer, B., \"Flux Vector Splitting for the Euler Equations\", Lecture Notes in Physics. 170, 1982, 507-512.","Haoui, R., \"Finite volumes analysis of a supersonic non-equilibrium flow around the axisymmetric blunt body\", International Journal of Aeronautical and space Sciences, 11(2), 2010, pp59-68. DOI:10.5139/IJASS.2010.33.1.059","Haoui, R., \"Effect of Mesh Size on the Viscous Flow Parameters of an Axisymmetric Nozzle\", International Journal of Aeronautical and space Sciences, 12(2), 2011,","Shapiro, A.H. (1954). The Dynamics and Thermodynamics of Compressible fluid flow. The Ronald Press Company, New York. Volume II. Ch.17.","H. Schlichting, Boundary-layer theory, 7th edition, McGraw-Hill, New York, 1979.","K. A. Hoffmann, Computational fluid dynamics for engineers, Volume II. Chapter 14, Engineering Education system, Wichita, USA, pp.202-235, 1995.\n[10]\tJoel H. Ferziger & M. Peric, Computational Methods for Fluid Dynamics, Chapter 8, Springer-Verlag, Berlin Heidelberg, New York, 2002, pp.217-259,\n[11]\tM-C. Druguet, \"Contribution to the study of nonequilibrium reactive hypersonic Euler's flows,\" Thesis of Doctorate. University of Provence, France, 1992.\n[12]\tL. Landau, E. Teller, \"Theory of sound dispersion,\" Physikalische Zeitschrift der Sowjetunion. 10, (1936), 34-43."]}

The aero-thermal analysis of a hypersonic vehicle is of fundamental interest for designing its thermal protection system. The aero-thermal environment predictions over several critical regions of the hypothesized lifting body vehicle, including the stagnation region of the nose-cap, cylindrically swept leading edges, fuselage-upper, and fuselage-lower surfaces, are discussed. The drag (A=70) and temperature (A=80) minimized sweepback angles are considered in the configuration design of the two hypothesized lifting body shape hypersonic vehicles. The main aim of the present study is to analyze and compare the aero-thermal characteristics of these two lifting body configurations at same heat capacity. Accordingly, a Computational Fluid Dynamics simulation has been carried out at Mach number (M-infinity= 7), H=35 km altitude with zero Angle of Attack. Finally, the material selection for thermal protection system based on these predictions and current methodology is described. (C) 2016 IAA. Published by Elsevier Ltd. All rights reserved.

Основни циљ овог рада је да се формирају заједнички критеријуми за оцену и мерење ефикасности ваздухопловних и копнених вишецевних бацача ракета смештених на копнене и ваздухопловне борбене платформе, ради употребе у јединственим војно - тактичким задацима ''здружене ватрене подршке''. У овом раду дефинисан је коефицијент моћи наоружања, као параметар квалитета ватрене моћи невођеног ракетног наоружања. Помоћу њега је мерена и дефинисана величина снаге ватрене моћи, као површински борбени еквивалент и нови исказ квалитета деловања на циљу. Анализом појединачне ефикасности ваздухопловних борбених платформи, у појединачним или групним тактикама деловања, појам организованог ракетирања из ваздуха сведен је на редно, паралелно и комбиновано дејство. Свођењем масе летелице на ЈУРИШНУ и СЛЕТНУ масу, уведена је нова класификација корисних терета ваздухопловних платформи погодна за директну оцену квалитета непосредне ваздухопловне ватрене подршке. Одговарајућим релативним коефицијентима, као мерама капацитета способности овакве ваздухопловне намене, исказана је технолошка повезаност ваздухоплова са његовим борбеним карактеристикама. За потребе вишецевних ракетних дејства са ваздухоплова и са копна и ради оцене њихових дејстава на површинске циљеве истородном муницијом, уведен је појам јединичне нормиране ракете и нормираног рафала. Различити услови употребе ракета при дејству из ваздуха и са копна, упоређени су и посебним поступком анализе лета и балистике на циљу, сведени на еквиваленте исказе за два аналогна деловања и то: бришући (хоризонтални) лет, који има аналогију у артиљеријским дејствима, такозваним снопом према његовој ширини, и обрушавајући лет који има аналогију у артиљеријском дејству снопом у једну нишанску тачку. За оба поступка деловања формирана је еквивалентна, просторно механичка слика нормираног лета, независно од типа ваздухоплова, коришћена за анализу експерименталних резултата погодака. Експерименталном анализом гађања утврђени су рентабилни критеријуми о димензијама циља ваздухопловства и упоређени са циљевима које користи артиљерија, при дејству невођеним ракетама. Експериментално и теоријски, на бази функција вероватноћа растурањаје, доказано је да однос величина циљева артиљерије и ваздухопловства приближно износи 1:10,8 у корист артиљерије. Допринос у раду представља и нормирање средње потрошње нормиране ракетне муниције, којом се делује н а циљ исте величине и истом ефикасношћу, и чији однос износи око 2,5 у корист артиљерије. Оваквим поступком је утврђено да нормирање артиљеријског модула за једначење рафала са ваздухоплова из једног лансера капацитета 4 до 5 ракета, може да се изврши са најмање 10 а највише 13 ракета истог нормираног калибра од 122 до 128 mm, да би дејства из ваздуха и са копна била упоредива и самерљива. Такође je усвојен појам деградације борбене моћи ваздухопловне платформе, као нови концепт процене умањења ефикасности ватрене моћи сваког узастопног рафала. Овај концепт је експериментално потврђен и моделиран посебном симулацијом. Утврђено је, да је ефекат деградације мањи код боље наоружаних ваздухопловних платформи. Овакви закључци имају техничко-технолошку логику и могу се усвојити као општи исказ умањења хипотетичке ефикасности ваздухопловне подршке употребом различитих летелица. Целина овог истраживања даје основ за даљу анализу цене- ефикасности употребе невођене ракетне муниције дејством из ваздуха или са копна. Рад је први корак у изједначавању критеријума за здружена ваздушно копнена дејства подршке ВБР-ом, као савременог концепта интервидовских ватрених способности, базираних на употреби компатибилних технологија у борбеним применама. The basic purpose of this paper is to form joint criteria for the estimations and measurements of efficiency of air force and army Multi Launch Rocket System (hereafter MLRS) weapon, mounted on the air and field platforms to use in the joint tactical fire support. Paper determines the coefficient of the weapon power as the measure of fire power quality for the unguided rockets. Using this criteria the value of the force of the fire power is also determined, as the surface targets efficiency equivalent of suppressive fire.By the metyhod of the particular air platforms efficiency anaizes, organized in the individual or grouped attack tactics, the MLRS efficiency on the ground targets is considered as unified in the genral form of ,serial, redundant or mixed employed sequences.By the redesigning of flight vehicle mass, on the Assualt and Landing values the new classifications of their payloads , are determined as the more applicable for the estimations of direct fire support quallity measure. Also, new relative coefficients of the air weapon capabilitues distinguish technology performances of air platforms and weaponarry as more precise determined. The norming rocket and norming ripple for the MLRS s is derived as unified ammunition, attack from the air and field platforms, in the aim to measure efficiency employments of surface suppresive fire. The different conditions of rockets employment from the air and field are compared by especial derived method of flight mechanics and terminal ballistics, redesigned on the analoguous attacks as it :horizontal sweeping strike and diveing strike from the air, as equal to the, beam point concentrated, or beam line concentraterd artilery fire. For the both methodologies the equivalemnt figure of space time flight mechanics, is norming, independent of airctraft type, as required for the experimental anaizes of shooting results. By the experimental analises the criteria of optimal surface targets dimensions are determined and calculated, for the both air and field support by rockets riples. Experimental and theoretically based on the probabilities dispersion functions is proved that the ratio betwen air and ground attacing surface targets, has to be about 1 :10.8 in the cost to artillery.Contribution is, also ,norming of the equallty rocket ammunition consumption as 2,5 ratio, in the cost of artilery tоо.The artilery ripple module is determined as the pacckage of 10 (minimum) to the 13 (maximum) rockets, as the equivalence to the air MLRS module of the 4-5 rockets in launching package of the 122 -128 mm calibrated rockets, to ballance same effects of launched fire from the air and ground by the efficiency. As the new concept for the diminshing estimations of air platforms combat power the term degradation is acptepted as the consequence of multi sequent fire ripples . This concept is proved experimentally and by modeling of the software simulation. The effect of degradation is finding as the less for the better weapon capacity air vehicles. These conclusions have technical technology approvals as the general expression for the hypothetically diminishing of efficiency in the air power support by using of different air vehicles. The comprehensive approach of this research gave base for the coast effectives considerations for the using of air and ground action by MLRS .The paper is the first step in the join of the criteria for the estimations of joint air and ground MLRS support as the advanced concept of multi-service fire capabilities based on compatible technologies using in the battle employments.

Рассмотрена эволюция ключевых научных достижений Харьковских ученых и их воспитанников в XIX–XXI вв. в области управления механическими системами: от паровых машин до уникальных космических аппаратов. Показано, как созданный учеными научный потенциал позволил Харькову стать ведущим центром создания систем управления для важнейших объектов ракетостроения и космонавтики; наукоемкой и высокотехнологичной продукции оборонного и гражданского назначения, подготовки специалистов. The paper researches the dynamic process of establishment and development scientific-pedagogical activity of professors of mechanics of Kharkov in the 19–21 centuries. The origination of the Ukrainian technical science in the field of theory of control systems is connected with the Kharkov. It discovered and explored the main scientific trends of evolution of establishing optimal control of moving objects and technological processes. Main phases of formation and development of research and design school of Kharkov, its earlier spacecraft related works, subsequent work in the present-day period and implications for the spacecraft industry in Ukraine are shown. Names of persons are referred to, which were associated with the Kharkov school or left it. The Kharkov oldest, rocket and space enterprises «Kommunar» and «Khartron» are the largest, producer’s control systems for ballistic rockets and spaceships. Additionally to specific space products (launchers, satellites, space components, etc.) scientists оf Kharkov also created the number of «common» products for the needs of machinery, power production, etc.

The basic purpose of this paper is to form joint criteria for the estimations and measurements of efficiency of air force and army Multi Launch Rocket System (hereafter MLRS) weapon, mounted on the air and field platforms to use in the joint tactical fire support. Paper determines the coefficient of the weapon power as the measure of fire power quality for the unguided rockets. Using this criteria the value of the force of the fire power is also determined, as the surface targets efficiency equivalent of suppressive fire.By the metyhod of the particular air platforms efficiency anaizes, organized in the individual or grouped attack tactics, the MLRS efficiency on the ground targets is considered as unified in the genral form of ,serial, redundant or mixed employed sequences.By the redesigning of flight vehicle mass, on the Assualt and Landing values the new classifications of their payloads , are determined as the more applicable for the estimations of direct fire support quallity measure. Also, new relative coefficients of the air weapon capabilitues distinguish technology performances of air platforms and weaponarry as more precise determined. The norming rocket and norming ripple for the MLRS s is derived as unified ammunition, attack from the air and field platforms, in the aim to measure efficiency employments of surface suppresive fire. The different conditions of rockets employment from the air and field are compared by especial derived method of flight mechanics and terminal ballistics, redesigned on the analoguous attacks as it :horizontal sweeping strike and diveing strike from the air, as equal to the, beam point concentrated, or beam line concentraterd artilery fire. For the both methodologies the equivalemnt figure of space time flight mechanics, is norming, independent of airctraft type, as required for the experimental anaizes of shooting results. By the experimental analises the criteria of optimal surface targets dimensions are determined and calcul

Рассмотрена эволюция основных научных достижений ученых и выпускников НТУ «ХПИ» в XIX–XXI вв. в области управления механическими системами: от паровых машин до уникальных космических аппаратов. Показано, как созданный учеными и выпускниками НТУ «ХПИ» научный потенциал позволил Харькову стать ведущим центром создания систем управления для важнейших объектов ракетостроения и космонавтики; наукоемкой и высокотехнологичной продукции оборонного и гражданского назначения, подготовки специалистов. The paper researches the dynamic process of establishment and development scientific-pedagogical activity of professors of mechanics of National Technical University "Kharkiv Polytechnical Institute» in the 19–21 centuries. The origination of the Ukrainian technical science in the field of theory of control systems is connected with the NTU «KhPI». It discovered and explored the main scientific trends of evolution of establishing optimal control of moving objects and technological processes. Main phases of formation and development of research and design school of NTU «KhPI», its earlier spacecraft related works, subsequent work in the present-day period and implications for the spacecraft industry in Ukraine are shown. Names of persons are referred to, which were associated with the NTU «KhPI» school or left it. The Kharkiv oldest, rocket and space enterprises «Kommunar» and «Khartron» are the largest, producer’s control systems for ballistic rockets and spaceships. Additionally to specific space products (launchers, satellites, space components, etc.) scientists оf NTU «KhPI» also created the number of «common» products for the needs of machinery, power production, etc.

Satellite launchers are submitted to severe acoustic loads mainly during lift-off where SPL achieve, at the upper parts, values within the range of 140-160 dB. Such an excitation can damage embedded elements, if energy attenuation measures are not adopted. In view of managing the PLF vibro-acoustic environment, numerical techniques are applied to predict elasto-acoustic behavior. This manuscript presents a numerical study on the design of acoustic insulation for the VLS-1 fairing compartment. An excitation profile based on the literature is applied on a SEA coupled model of this structural-acoustic system and absorbing materials are added to the model. Two parameters of the absorbing material layer are analyzed: thickness and covered area. Two NCT modeling approaches are used to simulate the effect of blanketing the VLS-1 fairing: acoustic materials Biot's parameters, given by the manufacturer, and material samples absorption coefficient, measured in a Kundt Tube. Results show that an increase in the blanket thickness from 7.62 to 12.7 cm results in a TL of 1.7 dB OSPL, while variations of up to 3.0 dB OSPL are calculated if the fairing cavity blanketed area varies from 30% to 100%.

Durante muchos años, las sondas estratosféricas han sido usadas para experimentos atmosféricos. Los nuevos globos de LATEX de bajo coste permiten poner hasta 4 kilogramos de carga de pago en el espacio cercano. Típicamente, los globos estratosféricos alcanzan hasta 37 km y son llenados de helio. Esta plataforma es adecuada para probar componentes COTS (Commercial off-the-shelf) en espacio cercano. De esta manera es muy barato validar nuevos componentes para el espacio, hace más barato ir al espacio. Antes de tener esta plataforma, la única manera de validar componentes era lanzando un cohete real en el espacio o a cuestas (piggyback) de otro lanzamiento real. En este trabajo final de carrera (TFC) se diseña y lanza una misión basada en una sonda estratosférica para probar la segunda etapa de una mini-lanzadera que está programada en unos meses. Este trabajo es realizado en paralelo con otros TFCs. El estudiante tiene que sincronizar la carga de trabajo con otros temas como la preparación del grano, la construcción de la tobera y el sistema de control de actitud. Otros subsistemas fueron probados en lanzamientos de sondas estratosféricas de la EPSC previos. Un sistema de seguimiento de la posición, basado en una radio VHF, será instalada para seguir toda la trayectoria, no solo para el vuelo del globo si no también de la segunda etapa hasta que sea tirado al mar. En este sentido, un tubo de lanzamiento será instalado en el globo de forma que asegure un mínimo ángulo y rumbo antes del lanzamiento. Este trabajo será realizado en colaboración con algún organismo espacial como el INTA. El lanzamiento será llevado a cabo bajo la supervisión de la autoridad de aeronavegación como la DGAC y el estado mayor. Usaremos para tal fin alguna base de lanzamiento como puede ser “El arenosillo” (España).