COMBINED CHANNEL PROCESSING TECHNOLOGY BASED ON MULTI-LAYER TEMPLATES

2021 ◽  
pp. 89-96
Author(s):  
А.В. Щеднов ◽  
В.П. Смоленцев ◽  
Н.С. Поташникова
Keyword(s):  
Rocket Engine ◽  
High Heat ◽  
Rocket Engines ◽  
Combustion Chambers ◽  
Bottom Part ◽  
Narrow Channels ◽  
Engine Cooling ◽  
The Cost ◽  
New Generation ◽  
Combined Channel

Рассмотрена технология изготовления дополнительных элементов систем охлаждения ракетных двигателей в форме местных углублений, расположенных на имеющихся фрезерованных каналах на наружных поверхностях камер сгорания и реактивного сопла. Такая проблема требует решения в перспективных изделиях с повышенной теплонапряженностью зоны горения топлива. Проведен анализ конструкции и возможностей обработки дополнительных элементов охлаждения в донной части и на боковых поверхностях узких каналов с ограниченным доступом инструмента в зону удаления припуска. Изучены новые конструкции инструмента для комбинированной обработки с использованием шаблонов различной конструкции и обоснована возможность их использования для изготовления углублений в каналах. Предложены новые способы комбинированной локальной обработки углублений с несимметричной геометрией сечения, форма которых обоснована в процессе отработки технологичности конструкции создаваемых двигателей, что ранее считалось неосуществимым или чрезмерно трудоемким. Исследована возможность многоместной обработки локальных углублений для дополнительного охлаждения в каналах на участках с переменным профилем камер сгорания современных и перспективных изделий по многослойным шаблонам. Здесь разработанные комбинированные технологии дают наибольший эффект и способствуют повышению ресурса двигателей новых поколений до уровня, обеспечивающего многократное увеличение количества безотказных пусков космических систем, что значительно снижает затраты на изготовление ракетных двигателей новых поколений The article considers the technology of manufacturing additional elements of rocket engine cooling systems in the form of local recesses located on the existing milled channels on the outer surfaces of the combustion chambers and the jet nozzle. This problem requires solutions in promising products with high heat stress of the fuel combustion zone. We analyzed the design and processing capabilities of additional cooling elements in the bottom part and on the side surfaces of narrow channels with limited tool access to the allowance removal zone. We studied new tool designs for combined processing using templates of various designs and justified the possibility of their use for making recesses in channels. We propose new methods of combined local processing of recesses with an asymmetric cross-section geometry, the shape of which is justified in the process of testing the manufacturability of the design of the created engines, which was previously considered impossible or excessively labor-intensive. We investigated the possibility of multi-site processing of local recesses for additional cooling in channels in areas with a variable profile of the combustion chambers of modern and promising products using multilayer templates. Here, the developed combined technologies give the greatest effect and contribute to increasing the resource of new-generation engines to a level that provides a multiple increase in the number of trouble-free launches of space systems. This significantly reduces the cost of manufacturing new-generation rocket engines

scholarly journals EVALUATION OF THE RELIABILITY TEST RESULTS OF A ROCKET ENGINE BASED ON A LOGICAL-PROBABILISTIC METHOD

2019 ◽  
Vol 27 (4) ◽  
pp. 21-24
Author(s):  
Sergey Mikhailovich Podolchak
Keyword(s):  
Rocket Engine ◽  
Probabilistic Method ◽  
A Priori ◽  
Rocket Engines ◽  
Test Results ◽  
Reliability Models ◽  
Complex Technical Systems ◽  
Priori Information ◽  
Theory Of Evidence ◽  
The Cost

A logical-probabilistic method for evaluating the test result is proposed, which is based on the theory of evidence of Dempster-Schafer with some assumptions that do not affect the final result. Currently, there is an acute question of creating new types of rocket technology in connection with a change in the situation on the international and domestic market. When creating new samples, it is necessary to pay special attention to the level of their reliability, but also remember to take into account the financial component of projects for the development and manufacture of products. In this regard, research is currently being conducted not only in the direction of increasing the reliability of complex technical systems, which include rocket engines, but also in reducing the cost of their refinement. One of the research options in this direction was proposed by the author in this work. The aim of the work and research as a whole was to demonstrate the capabilities of the chosen method for evaluating the test results, according to which it would be possible to draw conclusions about the success of the tests themselves. As studies have shown, the logical-probabilistic method for evaluating test results based on the Dempster-Schafer theory of evidence, due to the lack of a priori information, can be used in the development of new rocket engine models, but only in a narrow direction. More widely, this method can be used in the design of products based on accumulated experience (amount of information) on existing analogues. Dempster-Schafer proof theory can be applied at earlier design stages, but only in combination with other reliability models.

scholarly journals Original Romanian Research for a Rocket Engine with Multiple Combustion Chambers during 1940 - 1944

2020 ◽  
Vol 12 (1) ◽  
pp. 229-241
Author(s):  
Nicolae-Florin ZAGANESCU ◽  
Constantin-Marcian GHEORGHE ◽  
Peter KALMUTCHI
Keyword(s):  
Rocket Engine ◽  
Mechanical Equipment ◽  
Technical Solution ◽  
Rocket Engines ◽  
Centrifugal Pumps ◽  
Combustion Chambers ◽  
Bypass Valve ◽  
Fuel Tanks ◽  
History Of ◽  
Points Of View

The paper presents certain points of view regarding the history of Romanian rocket engines, during 1940-1944. Working independently of other scientists, during 1942 – 1944 the Romanian Nicolae Văideanu has invented and designed, independently of other researchers, a liquid fuel missile called UDOVILUL-V [3]. According to the design drawings, this missile was equipped with aerodynamically profiled propelling nozzles and was provided with a special alternator – distributor, the bypass valve adjusting the fuel components dosage in the two combustion chambers, in fuel tanks and pipes, while a special designed gas turbine was driving the centrifugal pumps and other mechanical equipment. Within his main patent the Romanian inventor has included the design of several components [2], [4], [5]. The technical solution of this outstanding design in rocketry development could provide 20kN thrust after 60 sec, enabling a speed of 3200 km/h [10].

Study of Hydraulic Characteristics of the Cooling Path of a Model Liquid Rocket Engine Manufactured using Additive Technology of Selective Laser Melting

2019 ◽  
pp. 41-52
Author(s):  
D.A. Yagodnikov ◽  
V.P. Aleksandrenkov ◽  
K.E. Kovalev ◽  
A.G. Grigoryants ◽  
A.A. Drenin
Keyword(s):  
Selective Laser Melting ◽  
Rocket Engine ◽  
Rocket Engines ◽  
Hydraulic Characteristics ◽  
Combustion Chambers ◽  
Laser Melting ◽  
Melting Technology ◽  
Model Liquid ◽  
Cooling Path ◽  
Liquid Rocket

The article discusses hydraulic tests of a model combustion chamber of a liquid-propellant rocket engine with a cooling path made using additive selective laser melting technology. The values of the coefficient of hydraulic resistance in the range of Re = 10--2500 are obtained and the influence of the design features of the cooling tract and its manufacturing technology on the hydraulic characteristics is determined. The results of the performed hydraulic tests confirm the possibility of using additive technologies based on selective laser melting technology for the manufacture of fire and power walls of combustion chambers of liquid rocket engines.

SIMULATION OF THE CURRENT-VOLTAGE CHARACTERISTICS OF SOLAR BATTERIES WITH CONSIDERING DECREASE OF LIGHTING DUE TO THE INFLUENCE OF JETS OF THE ELECTRIC PROPULSION

2019 ◽  
pp. 56-64
Author(s):  
Ya.N. MIGUNOV ◽  
V.V. ONUFRIEV
Keyword(s):  
Solar Cells ◽  
Temperature Gradient ◽  
Electric Propulsion ◽  
Protective Coatings ◽  
Rocket Engine ◽  
Solar Array ◽  
Rocket Engines ◽  
Lighting Conditions ◽  
Main Equation ◽  
Voltage Current Characteristic

A model for calculating the voltage-current characteristic of a solar array in the presence of a temperature gradient by its photovoltaic converters and their variable illumination due to possible pollution under the action of space factors, including operation of electric rocket engines, is described. The model is based on the main equation of a solar cell. In this case both a one-dimensional and a two-dimensional temperature gradients are taken into account. The principles of constructing a model are given, and the initial data selection is made. To simulate the lighting conditions of the solar array such a concept as effective illumination is used, i.e. the density of the radiation flux which falls on photovoltaic converters passing through the protective coatings. The features of simulation of the temperature distribution in the solar array and the effective illumination of its surface in cases of parallel, serial and mixed switching of solar cells are described. The calculation procedures and examples of solar cells are given. The construction of the model in universal mathematical package Mathcad is described. Some simulation results are discussed. Key words: solar array, mathematical simulation, illumination, temperature gradient, electric rocket engine, spacecraft, Mathcad.

Graphic method for assessing the margins of resistance to acoustic vibrations in the chambers of rocket engines by combustion noise

2020 ◽  
pp. 15-21
Author(s):  
R.A. Tsarapkin ◽  
V.N. Ivanov ◽  
V.I. Biryukov
Keyword(s):  
Rocket Engine ◽  
Spectral Characteristics ◽  
Combustion Process ◽  
Combustion Noise ◽  
Rocket Engines ◽  
Acoustic Vibrations ◽  
Statistical Regression ◽  
Unknown Parameters ◽  
Damping Decrement ◽  
Resonance Frequencies

An experimental method is proposed for estimating the damping decrements of pressure fluctuations in the combustion chambers of forced rocket engines. The method is based on the statistical processing of noise pressure pulsations in the vicinity of natural resonance frequencies for normal modes of acoustic vibrations of the reaction volume and the subsequent prediction of the instability of the combustion process relative to acoustic vibrations. Based on the theory of statistical regression for multidimensional experimental data, the problem of predicting unknown parameters of sample distributions is solved by asymptotic determination of the correlation coefficient of the damping decrement of pressure vibrations through optimal linear predictors and the Kolmogorov distribution. Keywords rocket engine, combustion chamber, acoustic vibrations, combustion noise, spectral characteristics, Kolmogorov criterion, damping decrement. [email protected]

Experimental Study on Heat Transfer Augmentation for High Heat Flux Removal in Rib-Roughened Narrow Channels

1998 ◽  
Vol 35 (9) ◽  
pp. 671-678 ◽  
Author(s):  
Md. Shafiqul ISLAM ◽  
Ryutaro HINO ◽  
Katsuhiro HAGA ◽  
Masanori MONDE ◽  
Yukio SUDO
Keyword(s):  
Heat Transfer ◽  
Experimental Study ◽  
Heat Flux ◽  
High Heat ◽  
High Heat Flux ◽  
Narrow Channels ◽  
Heat Transfer Augmentation ◽  
Rib Roughened

Development of Advanced High Heat Flux Cooling System for Power Electronics

2009 ◽  
Author(s):  
Yasuhisa Shinmoto ◽  
Shinichi Miura ◽  
Koichi Suzuki ◽  
Yoshiyuki Abe ◽  
Haruhiko Ohta
Keyword(s):  
Heat Flux ◽  
Power Electronics ◽  
Critical Heat Flux ◽  
Heating Surface ◽  
Narrow Channel ◽  
High Heat ◽  
High Heat Flux ◽  
Gap Size ◽  
Narrow Channels ◽  
Very High

Recent development in electronic devices with increased heat dissipation requires severe cooling conditions and an efficient method for heat removal is needed for the cooling under high heat flux conditions. Most researches are concentrated on small semiconductors with high heat flux density, while almost no existing researches concerning the cooling of a large semiconductor, i.e. power electronics, with high heat generation density from a large cooling area. A narrow channel between parallel plates is one of ideal structures for the application of boiling phenomena which uses the cooling for such large semiconductors. To develop high-performance cooling systems for power electronics, experiments on increase in critical heat flux (CHF) for flow boiling in narrow channels by improved liquid supply was conducted. To realize the cooling of large areas at extremely high heat flux under the conditions for a minimum gap size and a minimum flow rate of liquid supplied, the structure with auxiliary liquid supply was devised to prevent the extension of dry-patches underneath flattened bubbles generated in a narrow channel. The heating surface was experimented in two channels with different dimensions. The heating surfaces have the width of 30mm and the lengths of 50mm and 150mm in the flow direction. A large width of actual power electronics is realizable by the parallel installation of the same channel structure in the transverse direction. The cooling liquid is additionally supplied via sintered metal plates from the auxiliary unheated channels located at sides or behind the main heated channel. To supply the liquid to the entire heating surface, fine grooves are machined on the heating surface for enhance the spontaneous liquid supply by the aid of capillary force. The gap size of narrow channels are varied as 0.7mm, 2mm and 5mm. Distribution of liquid flow rate to the main heated channel and the auxiliary unheated channels were varied to investigate its effect on the critical heat flux. Test liquids employed are R113, FC72 and water. The systematic experiments by using water as a test liquid were conducted. Critical heat flux values larger than 2×106W/m2 were obtained at both gap sizes of 2mm and 5mm for a heated length of 150mm. A very high heat transfer coefficient as much as 1×105W/m2K was obtained at very high heat flux near CHF for the gap size of 2mm. This paper is a summary of experimental results obtained in the past by the present authors.

scholarly journals Modelling of new generation plasma optical devices

Nukleonika ◽  
2016 ◽  
Vol 61 (2) ◽  
pp. 207-212 ◽  
Author(s):  
Irina V. Litovko ◽  
Alexy A. Goncharov ◽  
Andrew N. Dobrovolskiy ◽  
Lily V. Naiko ◽  
Irina V. Naiko
Keyword(s):  
Low Cost ◽  
Rocket Engine ◽  
Cost Effective ◽  
Optical Devices ◽  
High Tech ◽  
Practical Applications ◽  
Plasma Accelerators ◽  
New Generation ◽  
Closed Electron ◽  
Positive Space

Abstract The paper presents new generation plasma optical devices based on the electrostatic plasma lens configuration that opens a novel attractive possibility for effective high-tech practical applications. Original approaches to use of plasma accelerators with closed electron drift and open walls for the creation of a cost-effective low-maintenance plasma lens with positive space charge and possible application for low-cost, low-energy rocket engine are described. The preliminary experimental, theoretical and simulation results are presented. It is noted that the presented plasma devices are attractive for many different applications in the state-of-the-art vacuum-plasma processing.

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