george surdu

Concerning the Evaluation of Trajectories Deviations Caused by the Perturbations Made when the Rocket Leaves the Rocket Launcher System

To achieve an accurate rocket launch, it is necessary to assess how the perturbations appearing w... more To achieve an accurate rocket launch, it is necessary to assess how the perturbations appearing when the rocket leaves the rocket launcher system, influence the rocket flight trajectory and shooting accuracy as well. Therefore, we will analyse the influence of the rocket launcher system oscillations, during the shooting, on the rocket movement. We are taking into account other perturbation factors that can appear during the shooting and the rocket flight in standard atmosphere.

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Considerations on Efficiency in Experimental Tests Specific for Projectiles of Low Caliber

Procedia Economics and Finance, 2015

In the latest period of time the lack of resources made us to be more carefully in spending them.... more In the latest period of time the lack of resources made us to be more carefully in spending them. In this context along time were developed different types of methods which permits to evaluate with maximum efficiency the resources needed in different types of products design jobs. Some of these methods in the present time are numerical simulations which are a good choice as an instrument for the resources consumption estimation. These types of methods are encouraged in ammunitions design too. As an example we can observe that some military standards encourage the use of numerical simulation in first steps of a product design or on his life cycle, before experimental testing, but not exclude experimental testing. To complete this approach the present paper comes with some models for the efficiency estimation taking into account the necessary resources for ammunition experimental testing, in general and ammunition consumption in experimental tests in particular. These models are based on statistical estimations and general probability theory, ammunition ballistic design theory with punctual estimation and reliable intervals for true value of a parameter in an imposed level of trust condition.

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In-house" software module for projectile's drag coefficient evaluation in case of small geometrical dimension tolerances: A solution for cost reducing

Drag coefficient is an important parameter in exterior ballistic which is used to evaluate the sh... more Drag coefficient is an important parameter in exterior ballistic which is used to evaluate the shape of projectile trajectory. The purpose of this study was to create a simple instrument for drag coefficient preliminary evaluation using the existing drag laws: 1943 law, 1930 law or Siaccis's law and his geometrical dimensions important for ballistics. The instrument mentioned before is represented by a software module which is based on an existing theoretical model, properly ajusted, for drag coefficient evaluation. This software module has the ability to evaluate also the influences for some geometrical dimension tolerances of projectile's shape against drag coefficient. The projectile's testing and evaluation represents an important step in ammunition design. In these kind of activities the consumption of resources is very high, because of aerodynamic tests or field tests. Aerodynamic tests are done to evaluate the projectile's aerodynamic coefficients. The most im...

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Protech "In-House" Software an Alternative for Projectile's Drag Coefficient Evaluation in Case of Small Tolerances of Its Geometrical Dimensions

SCIENTIFIC RESEARCH AND EDUCATION IN THE AIR FORCE, Jun 24, 2016

In this paper is described a software product for projectile's drag coefficient evaluation in cas... more In this paper is described a software product for projectile's drag coefficient evaluation in case of small finite differences of projectile's geometrical dimensions. The software is useful for engineers who work in research and ammunition design when is necessary to evaluate the preliminary projectile drag coefficient and its implications on trajectory. The paper offers an evaluation of projectile's drag coefficient by two different methods: numerical simulation using the flow around the projectile shape and using ProTech design software. The evaluation is made with two different software products, a fluid mecanics one and the "in-house" ProTech software instrument, by comparing the results for drag coefficient obtained using four different projectile shapes.

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Sustainable development a challenge for research in the field military equipment and space

Impact of Socio-economic and Technological Transformations at National, European and International Level, 2015

In general, military equipment has a destructive role on the environment and, therefore, in this ... more In general, military equipment has a destructive role on the environment and, therefore, in this domain can hardly find items which align to the concept of sustainable development, but there may be some opportunities to promote this concept complex one these being the development of applications or software tools. This paper focused on presentation of a research in the field of military technology from the perspective of sustainable development concept.

Sustainable development a challenge for research in the field military equipment and space

Impact of Socio-economic and Technological Transformations at National, European and International Level, 2015

In general, military equipment has a destructive role on the environment and, therefore, in this ... more In general, military equipment has a destructive role on the environment and, therefore, in this domain can hardly find items which align to the concept of sustainable development, but there may be some opportunities to promote this concept complex one these being the development of applications or software tools. This paper focused on presentation of a research in the field of military technology from the perspective of sustainable development concept.

“In – house” software module for projectile’s drag coefficient evaluation in case of small geometrical dimension tolerances: A solution for cost reducing

The Romanian Journal of Economics, 2015

Drag coefficient is an important parameter in exterior ballistic which is used to evaluate the sh... more Drag coefficient is an important parameter in exterior ballistic which is used to evaluate the shape of projectile trajectory. The purpose of this study was to create a simple instrument for drag coefficient preliminary evaluation using the existing drag laws: 1943 law, 1930 law or Siaccis's law and his geometrical dimensions important for ballistics. The instrument mentioned before is represented by a software module which is based on an existing theoretical model, properly ajusted, for drag coefficient evaluation. This software module has the ability to evaluate also the influences for some geometrical dimension tolerances of projectile's shape against drag coefficient.

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Dezvoltarea Durabilă O Provocare Pentru Cercetarea Din Domeniul Tehnicii Militare Şi Spaţiului (Sustainable Development a Challenge for Research in the Field Military Equipment and Space)

PSN: Sustainable Development (Topic), 2015

Romanian Abstract: In general, tehnica militară are un rol distructiv asupra mediului si, ca atar... more Romanian Abstract: In general, tehnica militară are un rol distructiv asupra mediului si, ca atare, in acest domeniu cu greu se pot găsi elemente care să se alinieze la dezideratele conceptului de dezvoltare durabilă, insă pot exista unele posibilităţi de promovare a acestui concept complex, una dintre acestea fiind realizarea de aplicaţii sau instrumente software. Lucrarea de faţă are ca principal scop prezentarea unei cercetări in domeniul tehnicii militare din perspectiva conceptului de dezvoltare durabilă.English Abstract: In general, military equipment has a destructive role on the environment and, therefore, in this domain can hardly find items which align to the concept of sustainable development, but there may be some opportunities to promote this concept complex one these being the development of applications or software tools. This paper focused on presentation of a research in the field of military technology from the perspective of sustainable development concept.

Copper Based Alloys Hardenable by Precipitation

Chemical engineering transactions, 2021

The paper presents the experimental research conducted with the purpose of accomplishing long pro... more The paper presents the experimental research conducted with the purpose of accomplishing long products out of special copper-based alloys, from Cu-Cr-Zr systems, hardenable by precipitation, appropriate for large domains of utilization within top industries realized by modern casting – deforming procedures. Therefore, one of the modern technologic alternatives meeting these requirements is horizontal continuous casting which ensures the realization of long semi-fabricated materials out of special alloys that can be used in cast state and/or plastically deformed, in warmth and/or cold, for the accomplishment of certain products required on the market. The effect of precipitation function of hardening degree applied to the samples put in solution is quantified on consecrated compositions of the Cu-Cr-Zr alloys, containing ˜ 1% Cr and ˜ 0.12% Zr respectively, after the solubility treatment. The macroscopic resistance determinations as well as the electronic microscope and X-ray investi...

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Design of an Electrical Hydro-Pneumatic Station Powered by Waves with Hydrodinamic and Finite Element Software

To convert wave action into useful energy, a power plant must provide a way for waves to drive so... more To convert wave action into useful energy, a power plant must provide a way for waves to drive something, such as hydro-pneumatic station. This system traps waves in a partially submerged, artificial chamber with a hole in one wall above the water line. The hole leads to an air-driven turbine. As the crest of a wave enters the chamber, it raises the water level quickly, pushing the air above the wave through the hole and spinning the turbine’s blades. The turbine is designed to turn the same way no matter which way the air flows through his, so the machine also runs as the retracting wave sucks air back into the chamber. In the paper are presented numerical results of the simulation of the oscillatory wave motion and the oscillatory airflow through the chamber and numerical results obtained with a finite element software

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Instrumente software realizate „in-house” pentru evaluarea teoretică a parametrilor balistici

În proiectare, achiziţie sau expertiză tehnică apare din ce în ce mai acută nevoia de instrumente... more În proiectare, achiziţie sau expertiză tehnică apare din ce în ce mai acută nevoia de instrumente la costuri reduse capabile să ofere rapid o evaluare teoretică iniţială a anumitor parametrii balistici esenţiali pentru o muniţie sau o gură de foc. Lucrarea de faţă vine în întâmpinarea unei astfel de nevoi prin propunerea unei aplicaţii software modulare capabilă să îndeplinească unele din cerinţele mai sus amintite. În cadrul lucrării se va prezenta succint modulul de balistică interioară cât şi posibile aplicaţii la care acesta este util.

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Evaluation of Peroxide-Based Compositions Containing Amino Acid Surfactants

Proceedings

Chemical warfare agents are a real threat to the security of mankind and efforts are constantly [... more

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