Department of power plant thermogas dynamics

Head of department – D.Sc., Professor Hennadii O. Strelnykov

Hennadii O. Strelnykov

Field of research – thermogasdynamics and heat-mass exchange in rocket and space engines, heat power and technological equipment; mechanisms, models and research methods of gas flow control characteristics in rocket engines and elements of gas-jet technological equipment; expanding the functionality and improving the performance of control systems for the thrust vector of rocket engines and the grinding process of bulk materials.

Rocket Engine Thrust Vector Control

The fundamental mechanisms of the perturbation of a supersonic flow by discrete and distributed sources of mass and heat, liquid and gas jets, solid obstacles, technological imperfections and erosive drifts on a streamlined surface have been revealed. Methods have been developed to calculate the local and integral, static and dynamic characteristics of the gas flow control process in the nozzle of a rocket engine. The methods are based on theoretical developments and experimental data obtained on unique research complexes created in the ITM. Studies of supersonic flow disturbances on models and full-scale engines have confirmed the developed physical and mathematical simulations. The research results created a scientific basis for the development of new technical solutions for the thrust vector control of traditional and new types of nozzles of rocket engines operating on liquid, solid and gaseous fuels.

Research on the control of supersonic flow of rocket engines has been conducted in close collaboration with the Yuzhnoye State Design Office . The thrust vector control system for rocket engines by injection into the supersonic part of the nozzle of fuel combustion products has been used by the Yuzhnoye State Design Office in a number of liquid and solid propellant rocket engines, in particular 15D12, 15D169, 11D25, RDTT 3D65, 15D206 liquid propellant engines.

In the process of scientific support of their creation, the static, dynamic, heat-and-mass exchange and operational characteristics of the traction vector control systems and the engine as a whole (as an object of regulation) were studied, calculation methods and recommendations for the design and development of such engines were developed. A mathematical simulation of solid propellant rocket engine with chamber gas injection into the supersonic part of the nozzle as an object of regulation has been developed.  The possibility and appropriateness of the programmed regulation of the second engine fuel consumption by the standard side-force controls (injection valves) are shown, which allows expanding the functionality of the solid propellant rocket engine and increasing its energy characteristics.

Created for the first time in the practice of rocket science, these engines made it possible to develop rocket stages unsurpassed to date by the high level of energy, dynamic, overall and operational characteristics.

Scientific support was provided at all stages of development of these engines, including flight tests. In particular, the results of studies of gas-dynamic control of the thrust vector were used to develop the conclusion of the state commission on determining the causes of the emergency flight design test of the rocket engine 11D25 of the Cyclone-3 rocket No. 40 L.

Further research in this area has proposed new methods, schemes and devices to control the thrust vector of liquid rocket engines of stages of launch vehicles and upper stages of spacecraft relative to the engines of upper stages of rockets (such as RD11D25, RD861K) and upper stages of spacecraft, which are characterized by high degrees gas expansion in the nozzle.

A new concept has been developed to control the thrust vector of a rocket engine – a combination of mechanical (swinging engine or nozzle) and gas-dynamic (disturbing supersonic flow in the engine nozzle) systems. An advantage of the new concept is the possibility of creating an unlimited amount of programmed control effort and parry with a high frequency of small-sized flight disturbances with virtually no loss of engine specific impulse. This significantly increases the reliability of the control system (due to duplication). A new concept has been developed to control the thrust vector of a rocket engine – a combination of mechanical (swinging engine or nozzle) and gas-dynamic (disturbing supersonic flow in the engine nozzle) systems. An advantage of the new concept is the ability to create an unlimited amount of software control effort and parry with a high frequency of small-sized flight disturbances with virtually no loss of specific engine impulse. This significantly increases the reliability of the control system (due to duplication).

A solution has been developed to increase the density of the space rocket layout, the energy-mass characteristics and the reliability of the nozzle’s altitude by using additional discharged tanks, and the gas-dynamic control of the engine thrust vector (supersonic flow disturbance in the engine nozzle).

The advantage to control the thrust vector by injection into the nozzle of the oxidizing component of the fuel, in particular through a solid interceptor, which extends into the flow, is shown. The operability of new circuits and designs of interceptor devices is confirmed by their purges in cold air and fire tests as part of the rocket engine and solid propellant rocket engine.

New nozzle configurations

It is shown that in conditions of tight overall limitations for tight configurations of solid-fuel multi-stage rockets operating on metallized fuel, new nozzle configurations will be optimal. New nozzle configurations and software and methods to calculate their characteristics have been developed. It is shown that the scheme of a disk nozzle with a flowing central body developed at the ITM is promising, which makes it possible to reduce the longitudinal dimensions of the nozzle and to control the thrust vector of the engine, both in magnitude and direction.

Important results have been obtained in the field of hydrodynamics and unsteady heat-and-mass transfer in multilayer structures of complex shape and channels of variable cross-section with a two-phase flow of liquid and gas, on the basis of which methods have been developed, calculations have been made and recommendations have been developed to ensure optimal thermal conditions and parameters of liquid rocket engines with multiple starts in the period of its shutdown.

Fundamentally new rocket engines with a detonation process of burning fuel in a chamber have been developed and investigated. The advantages of detonation devices for solving new problems in rocket and space and other fields of technology are shown, in particular, to increase the thrust vector control efficiency when solving various applied issues, separation and removal of a rocket radome fairing, generating a working fluid for spacecraft control systems, sequentially fading multi-stage design rockets, etc.

Technological processes

At the ITM experimental base, together with the Yuzhnoye State Design Office, special boilers “Fluidized bed”, “Cyclone”, “Emulsifier” were created and the processes of burning lump coal in a furnace with a circulating fluidized bed were investigated. New methods are proposed for organizing a process above the bottom grate with gas-dynamic transportation and unloading of ash and slag waste to eliminate the diffuser effect leading to instability of the gushing layer during lump coal transportation.

The processes of fine cleaning of flue gases using the hydrodynamic trapping device “Emulsifier” have been investigated. The optimal hydrodynamic, geometric, structural and operational parameters of emulsifier devices have been determined. The results obtained on the improvement of the furnace for coal combustion and flue gas treatment were used in the modernization of Karagandaenergo, Alma-Ataenergo, in Ukraine Mironovskaya State District Power Plant and others. New methods and devices have been developed for burning various fuels, which are based on an organized pulsed combustion mode, which provide economic, environmental and operational advantages over existing ones. The experimental studies of the burners were carried out at the stands created in the ITM (stand “Teploapparat”), and at the experimental base of the Yuzhnoye State Design Office. Experimental models of burner devices for Azot Enterprise have been developed, manufactured and tested – with respect to the combustion chamber of the nitrous gas heating system in the production of nitric acid at Bagleykoks; Gordorremstroy, etc.

The balance, simulation, dynamic, stochastic models of fine grinding of bulk materials have been developed to identify the technological modes of grinding and increase the efficiency of the process. A collar mathematical simulation of the process based on Markov chains based on the results of acoustic monitoring has been developed. Acoustic efficiency parameters and an optimality criterion for the operation of a jet mill have been established. The possibility of optimizing jet grinding of mineral raw materials based on the results of acoustic monitoring of the process is shown. Methods of visualization and optimization of grinding using information technology have been developed. This allowed us to achieve the necessary technological indicators while reducing energy consumption and observing control dispersion. A method for controlling the dispersion of a material based on acoustic monitoring of a process has been substantiated. The “Granulometer” installation has been developed to determine the particle size distribution of materials in an energy carrier stream. The developed methodology for controlling the quality of the crushed product significantly (30 times) accelerates the process of determining the fineness of the finished product, allows you to improve the quality of the finished product and reduce energy consumption when turning off the processing. All studies were tested in the industrial conditions of the Volnogorsk Mining and Metallurgical Combine.

The results obtained are based on theoretical studies and experiments based on the ITM NAS and the Civil Aviation Administration of Ukraine, including research complexes of thermogasdynamics of rocket engines and technological processes: high costs and pressure; gas dynamics of controlled flows; detonation devices; gas-jet grinding transportation and drying of bulk materials; heat and mass transfer.

Based on the research results, new technical solutions have been developed, more than 100 of which are protected by copyright certificates and patents for inventions.

It should be emphasized, the great contribution to the study of the former head of the Kovalenko Nikolai Dmitrievich, who was the head the department in 1971-2017. Kovalenko N. D. was the laureate of the State Prize of Ukraine for the development of the fundamentals of the gas-dynamic thrust vector control system for solid propellant rocket engines; Laureate of the National Academy of Sciences of Ukraine named after M.K. Yangel for the development of power plants that provide high performance aircraft; honored Worker of Science and Technology of Ukraine, holder of a number of medals and orders.

Some of the department results are summarized in numerous monographs, including:

  1. Kovalenko N.D. Perturbation of a supersonic flow during mass heat supply. Kiev: Naukova Dumka, 1980 .– 224 p.
  2. Kovalenko N.D. Unsteady Thermal Processes in Flying Vehicle Power Plants (in Russian) Kiev: Naukova Dumka, 1988. 224 pp.
  3. Kovalenko N.D. Supersonic Gas Flow Control in Jet Nozzles (in Russian) Kiev: Naukova Dumka, 1992. 208 pp.
  4. Kovalenko N.D. Gas-dynamics of Supersonic Truncated Nozzles (in Russian) Kiev: Naukova Dumka, 1993. 224 pp..
  5. Strelnikov G.A. Adjustable Short-length Supersonic Nozzles (in Russian) – Dnepropetrovsk: State University, 1993. 30 pp.
  6. Kovalenko N.D. Rocket Engine as an Executive Device of the Rocket Flight Control System (in Russian) – Dnepropetrovsk: Institute of Technical Mechanics of the NASU and the NSAU, 2004. – 412 pp.
  7. Pryadko N.S. Acoustic studies of jet grinding / LAP LAMBERT Academic Publishing. – 2013. – Saarbrucken Germany. – 172 pp.
OFFICE ADDRESS:Institute of Technical Mechanics , 15 Leshko-Popelya St., Dnipro, Ukraine  49005
PHONE NUMBER:+38-056-372-06-45

The “Technical Mechanics” Journal

Frequency: 4 times a year

Languages: Ukrainian, English

Editor-in-Chief: Oleg V. Pylypenko, Academician of the National Academy of Sciences of Ukraine