Дата публикации: 05 ноября 2022
Автор(ы): Konstantin FROLOV, A.Blaqonravov →
Публикатор: Научная библиотека Порталус
Рубрика: ТЕХНОЛОГИИ →
Источник: (c) "Science in Russia" Date:01-01-2000 →
Номер публикации: №1667677425
Konstantin FROLOV, A.Blaqonravov, (c)
by Academician Konstantin FROLOV, Director, A. Blagonravov Institute of Mechanical Engineering (IMASh), RAS
The Academic Institute of Mechanical Engineering- a center of basic research in the field-was established by the Presidium of what was then the Academy of Sciences of the USSR on November 13, 1938. Three days later there followed a joint session of what was called the Central Committee of the Research Workers' Union and its activists. The Union passed a resolution stressing as a timely measure the establishment of this Institute within the academic structure as "a competent body for moulding the general policy in the field of mechanical engineering". The initial staff of the new research center numbered 26.Today the Center, commonly known in this country by its acronym IMASh, is a well- established leader in the field of technical sciences and enjoys broad recognition both at home and abroad.
Considering a historical perspective, IMASh has been credited for its unique contributions to the progress of Russia's mechanical engineering in the years prior to 1941-the start of the Great Patriotic War with Nazi Germany. In the subsequent years IMASh continued to provide its invaluable contribution to Russia's war effort and after the war IMASh researchers focused on the overwhelming problems of Russia's post-war economic restoration which necessitated a whole range of both fundamental and applied studies.
The eventful history of IMASh is inseparably linked with this country's leading schools of research associated with the names of such prominent scientists as Academicians Yevgeny Chudakov, Alexander Blagonravov, Ivan Artobolevsky, Nikolai Bruyevich, Vladimir Dikushin and Yuri Rabotnov as well as Members of the Academy of Sciences of Ukraine V. Kononenko and S. Serensen, and Professors A. Dyachkov, I. Kragelsky, A. Petrusevich, S. Pinegin, N. Prigorovsky and M. Khrushchev, to name but a few.
The founding father of IMASh and its first director-the post he retained to the last days of his life (from 1938 to 1953)-was Academician Yevgeny Chudakov who helped lay the foundation of Russia's automobile industry. His studies on the theory of stability and steering control of automobile won international recognition. This area of research has always been in the focus of attention of our specialists and quite recently research agreements were signed with this country's leading Moskvich and ZIL car factories. For several years now IMASh experts have been engaged in studies on car acoustics in cooperation with the big GAZ Automobile Plant in Nizhny Novgorod.
From 1954 to 1975 the director of IMASh was Academician Alexander Blagonravov (he also held the military rank of Lieutenant-General). He was also Chief of the Russian Artillery Academy and won recognition for his weapons research. At the same time he provided a tangible contribution to studies of the upper atmosphere with the help of geophysical rockets. In 1978 IMASh was named after Academician Blagonravov.
In 1975 the post of its director was given to the author of this article. And it should be mentioned at this point that, even despite some obvious economic problems of the current transition period, the center
has been actively engaged in the development of advanced rocket and space technology.
The Department of Technical Sciences of the USSR Academy of Sciences ceased to exist in 1963, and while remaining under the general methodological guidance of the Academy, IMASh was subordinated first to the State Committee for Automation and Mechanical Engineering and later placed under the Ministry of Machine-Tool Industry. Such "handovers" interfered with the normal operating pattern of the center while promoting in no way the progress of domestic research in this important field. Persistent efforts on the part of the IMASh management to reinstall its original academic status were crowned with success in 1980.
The program of IMASh research for 1975-1980 covered space technology, vibration protection, development of new materials and research in aircraft, nuclear and certain special areas of engineering. As the vital importance of continued development of engineering studies in this country became increasingly clear, it was decided to set up an IMASh branch, first in Sverdlovsk (now Ekaterinburg) in 1985, and later on in St. Petersburg, Nizhny Novgorod, Samara (former Leningrad, Gorky and Kuibyshev) and also in Saratov. In a bid to increase the role of the Academy in engineering research the Department of Problems of Control Mechanics was transformed into the Department of Problems of Mechanical Engineering and Mechanics of Control Processes. It was also assumed that with the subsequent development of IMASh sister centers the Department will achieve an independent status-a problem which acquires particular importance today.
The list of R&D projects tackled by IMASh experts covers methods of increasing the durability, dependability and safety of engineering structures, dynamic stress, vibroacoustics, applications of new composite materials and ways of optimizing the aerodynamics of mechanical systems. IMASh scientists are also working on robots, doing basic research in mechanics and investigating the safety of complex engineering structures.
As follows from the brittle failure theory and non-linear mechanics, diagrams of destructive deformations and viability criteria assessments, different engineering structures possess different life spans. Pipelines, for example, can be exposed to what experts call "monocyclic fatigue" caused by load variations during the day. This factor is often responsible for some serious damage and even accidents. And on the whole, as experts point out, the life span of modern power and transport systems varies from fractions of a second to several decades. On the strength of these facts scientists in this country have developed methods of stress analysis in three- dimensional photoelastic models of structures (congealed, with inserts examined in scattered light); in highspeed machine rotors (turbo-pumps, separators, centrifuges, etc); stress assessment in automobile tyres with the help of what are called photo- elastic insets.
IMASh scientists have developed various types of what they call "technosensitive" coatings and methods of their application; rosin (for temperatures from -200 to +1,200C) and glass-enamel coatings (for temperatures from -250 to +400C) operating in oils, water, cryogenic liquids, etc. These are functioning in the conditions of varying pressure, and vibration stresses and under some extreme impacts of liquid- metal, gas, steam and water cooling agents and radiation.
One should also mention the important contribution of IMASh scientists to the theory of durability, service life, dependability and safety of big electrical machines, such as some unique thermal and hydraulic turbines of 200 MW; neutron power reactors WER-210, WER-365, WER-440, and WER-1,000 for power stations located in Russia, Ukraine, Czechy, Slovakia, Finland, Germany, Bulgaria and Hungary; for fast-neutron power reactors BN-350, BN-600 and BN-800(*); for the channel-type power reactors of type RBMK; thermonuclear units TOKAMAK T-14 and ITER ANGARA-5(**); nuclear central heating stations AST-50; nuclear steam generators for surface and sub-surface vessels; for the Energiya-Buran space shuttles; giant wind-tunnels T-128, T-101; aircraft systems NK-86; TU-204; oil and gas pipelines; unique chemical complexes of up to 50,000 m3 (in Budyonovsk, Dzerzhinsk, Surgut).
IMASh experts and engineers have also developed new versions of moon rovers, docking mechanisms for spacecraft, robots, manipulators and equipment for deep-sea research.
The operating velocities of modern machinery have considerably increased over the past decades, resulting in increased dynamic stresses and higher levels of noise and vibration. Over the past few years IMASh scientists have stepped up research into methods of noise and vibration control and what they call a "man-machine- environment" system which is evolving into a separate area of research.* This is especially important in terms of utilizing resonance and vibration effects for the development of new high-economy and high-output machines for the mining of hard rock; crushing, mixing and transportation of loose material; rolled iron for ferroconcrete parts; and boosting the strength of machine parts. The same line of research is expected to produce new anti-vibration protective devices for operators of high-speed transport facilities and aircraft.
The simplest way of combatting vibration consists in eliminating its source (such as disbalance of rotating parts of machinery). In addition to using the traditional balancing methods one can also use lasers. With their help any rotor disbalance, for example, can be detected and eliminated at one stroke, so to say (laser beam simply evaporates any excessive material mass). The procedure does not require participation of a specially trained operator, which paves the way to its partial or complete automation. In conjunction with electronic computers, laser balancing machines can be used to "rectify" rotors of one hundred tons and more.
IMASh scientists have worked out the basic principles of designing what they call low-noise machines with low levels of vibration. They have produced a range of new physical models of sound generation in certain sources of mechanical, aero and hydrodynamic nature. Improved models of
* See: V. Subbotin, "Nuclear Power: From the Past into the Future", Science in Russia, No. 6, 1996, No. 1, 1997-Ed.
** See: V. Matveyev, A. Perekrestenko, "Newborn in Troitsk", Science in Russia, No. 6, W9. - Ed.
* See: K. Frolov, "We Vibrate Because We Live", Science in Russia, No. 5, 1995. - Ed.
gear drives with better dynamics have been suggested, which make it possible to pre- calculate their vibrations (due to some processing and assembly flaws and elastic deformations).
IMASh experts have developed mathematical ways and means of measuring the biomechanics of a machine operator which help reduce vibration stresses and the impact of other adverse factors on the environment. Computerized vibration and laser stands have been developed for studies of ergonomic aspects of the functioning of man and machine under some extreme conditions which make it possible to predict interactions within the "man-machine-environment" system. Methods have been suggested for improving driver comfort in interior vehicle design in keeping with the criteria of ergonomic compatibility. On the basis of analysis of behavior of mechanical systems and operators under microgravity impacts, steps can now be taken for what are called medico-biological provisions of ensuring the safety and effective performance of space crews, maintaining their health and long "service life".
IMASh scientists have also developed techniques and equipment for ultrasonic therapies and surgery. A set of silicon-sapphire sensors has been provided for pressure measurements in the human body.
IMASh scientists have suggested a mathematical model of vibration loads and damping in spacecraft. Limiting values have been determined for oscillating-damping systems taking into consideration the active criteria involved. Optimal designs have been worked out for what is called a passive-active system of vibration damping for spacecraft. This technique is based on unique methods providing for an optimal combination of wide-band compensation of dynamic stresses and controlled damping.
IMASh scientists have been involved in coordinating design principles for interfaces(*) between the Russian and American sections of the Mir and Alpha international space stations (in conjunction with the Energiya R&D Complex and the Lavochkin Aerospace Center). Methods of assessment have been developed of the effect of aerodynamic factors on the relative movements of orbital systems consisting of two interconnected space objects.
IMASh scientists have designed and built what they call a system of adaptive (self- adjusting) manual
* Interface-a place or piece of computer hardware for information exchanges. - Ed..
control for the MIG-21 BIS aircraft; an automatic landing system for MIG-29; software for the assessment of altitude-velocity parameters of the Buran space shuttle; a measuring complex for the determination of amplitude and phase-frequency characteristics of dynamic objects. An integrated automated system has been developed for ground tests of space probes: a vibrostimulation unit for therapeutic applications; a simulator of human walking movements within restricted space, called Vibroscanner, and a Vitekor device for vibration testing and correction of physiological functions.
Of basic importance for the development of aerospace technologies, atomic power generation, studies of the ocean and of the deep strata of the earth crust, and also for the development of new farm machines and for the automation of technological processes have been theoretical and applied studies by IMASh scientists of problems of tribology (science dealing with the design, friction, wear and lubrication of machine parts), and of ways of improving the technical standards, dependability and service life of new generations of machinery and equipment and reducing the metal consumption involved. Within this area theoretical and experimental studies have been conducted into the heat-physics of rapid friction processes. What are called magneto-liquid bearings have been designed with a wide range of effective viscosity parameters leading to the development of what are called magneto-controlled damping devices, dampers of oscillations and shocks, and magnetorheological instruments for high-precision abrasive processing of materials. New anti-friction materials have been developed on the basis of heat-resistant plastics. Tests have been conducted on using water as lubricant for high-velocity shaft bearings and vacuum ionic-plasma technologies suggested for their surface treatment.
Laser methods have been suggested for the surface treatment of parts in friction and of laser-plasma application of metal ceramics. The layer thickness in this method is 1- 2 mm without surface melting and the hardness for medium-carbonic steel reaches 58- 61 HRC; with laser emissions of 1.5-2 KW the capacity can be as high as 1 cm2/sec. Thanks to a high rate of cooling the structure of fine-grain martensite(*) steel obtained is different from that produced by volume hardening and has smaller (by 3 to 4 times) grain size.
As a result of these techniques coatings of refractory compounds-titanium nitride and aluminum, complex nitrides and oxides of titanium or aluminum, etc.-acquire wear resistance at the level of tungsten carbide alloys which offers considerable savings of high-alloy steel (engine bearings produced by this method boast of increased load resistance and longer service life). The newly developed laser methods of cermet application on the surface of friction parts operating in highly abrasive conditions, under high loads and temperature changes provide for a combination of a high plasticity with increased hardness of such items.
In the field of theory of mechanisms IMASh experts are working on unique systems which determine the basic avenues of digital control of machines and also bioelectrical control of artificial limbs. Methods of remote control of the damping characteristics of the above make it possible to "prepare" such items for an effecting damping of vibration
* Martensite - the hard constituent of which quenched steel is chiefly composed as a result of polymorphous transformations.-Ed.
and shock loads at the moments of their anticipated increase, such as during space dockings or landings of spacecraft.
Another area of IMASh research covers what are called modular principles of production of technical parts. This provides for a high degree of flexibility and accelerated rate of technological processes involved, bringing the production time and labor expenses down to 20-10 percent.
IMASh scientists are also investigating what they call comprehensive pollution-free and energy-saving technologies including the utilization of secondary heat from sewage and heating pipelines with the help of special pumps (in central heating systems), the cleaning of air (at transport facilities and hazardous industrial premises) from CO, NO and other pollutants with the help of microbiological filters; industrial water treatment with the aid of membrane filters.
In recent years IMASh scientists conducted investigations under some international agreements and contracts for the development of new and promising mechanical designs, reduction of filtration and aero and hydro-dynamic loads, boosting the durability and dependability of space systems in the conditions of high and cryogenic temperatures (McDonnal Douglas, USA); using safe and environment-friendly technologies in power generation and industrial production (ASME, USA). Working in cooperation with Polish researchers from Warsaw and Radom, IMASh scientists have been studying ways of prolonging the service life of tools and machines; joint studies with colleagues from the Norwegian Academy have been focusing on problems of engineering safety. IMASh scientists have also been cooperating with experts from Vietnam on problems of vibration analysis of machinery operating in the tropics, and joint studies with experts from the Special Metal Co. (Republic of Korea) have been focusing on some pioneering metal rolling technologies.
IMASh plans for the start of the new century cover the development of basic dual- purpose technologies which will promote a radical reequipment of civil engineering in areas like the technologies of new composite materials, high-strength and temperature-stable carbon and low-alloyed steel for the building construction and engineering industries. New technologies of production of super-light alloys on the basis of aluminum, magnesium, titanium and beryllium are another line of IMASh research.
Опубликовано на Порталусе 05 ноября 2022 года
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