Department of aerogas dynamics and technical systems dynamics

Head of department – Corresponding Member of the National Academy of Sciences of Ukraine,
D.Sc., Professor 
Valerii I. Tymoshenko

Valerii I. Tymoshenko

Fields of research :

aerogasdynamics of launch vehicles, descent vehicles, hypersonic ramjet engines, and thrusters; theoretical and experimental study of jet flows; launch vehicle takeoff gas-dynamics;

mathematical models, methods and algorithms for the study of the functioning processes of promising and modernized controlled dynamic systems (CDS) in various operating conditions using objective data on monitoring their current state by on-board means; ways to increase target CDS;

heat and mass transfer in process apparatuses – mathematical simulation of gas-dynamic processes, heat and mass transfer, including studies of high-temperature equilibrium and nonequilibrium physicochemical, gas-phase and heterogeneous processes in the elements of technological devices in power engineering, metallurgy, mechanical engineering and other industries.

Main results of fundamental research


Aerogasdynamics of space rocket systems

  • supersonic and hypersonic flow around isolated bodies and full configurations of launch vehicles, equipped with wings, controls and stabilization. A zonal method has been proposed to calculate the distributed and integral aerodynamic characteristics of elongated bodies with control and stabilizing devices at supersonic Mach numbers. Methods and software have been created to make it possible to interactively calculate the supersonic flow around aerodynamic configurations with the arbitrary configuration of controls and stabilizing devices on the body;
  • hypersonic flow about descent vehicles under conditions of thermochemical destruction of the heat-resistant coating. The results of studies of the effect of destruction of the heat-resistant coating on the flow around aircraft.


Improving the efficiency of using the resources of a controlled dynamic system (CDS) based on its active movement control using objective data on monitoring the current state of the CDS using on-board means:

  • algorithm synthesis for actively suppressing flexural vibrations of the CDS housing in the output section based on a mathematical simulation of flexural vibrations, which describes the reaction of the CDS housing to a set of external disturbances and is formed by reconstructing the current shape of the flexible axial line of the housing from measurements;
  • algorithm synthesis for active control of the current hydrodynamic situation in fuel tanks on the content of free gas inclusions at the inlet of primary LPRE using the results of measurements of the current values of the real pressure field parameters with subsequent identification of the hydrodynamic conditions in the fuel tanks by the content and movement of the free gas inclusions.


  • methods and programs to calculate duct flows in the air intake devices of a ramjet. The influence of the duct geometric shape, the Reynolds number, and the flow regime (laminar or turbulent) on the pattern of flow deceleration has been studied.
  • fuel mixing and combustion in a cocurrent air flow in combustion chambers of a ramjet. Rational mathematical simulations, algorithms of their numerical implementation and the corresponding simulation software have been formulated. By using this software the possibility has been investigated to reduce the area of the fuel ignition and combustion due to the choice of rational parameters of the fuel jet flow.
  • design and methods have been developed and created for conducting operational complex calculations of thermogasdynamic processes in ramjet elements integrated with the aircraft body, in a two-dimensional approximation by marching methods.


  • interaction of subsonic and supersonic jet flows with a cocurrent supersonic and subsonic flow. Formulations of the corresponding problems as viscous interaction problems have been proposed and effective algorithms for their solution have been developed. Software and methods have been created to simulate afterburning rocket engine combustion products in atmospheric oxygen and water supply on jet parameters. The basic regularities of the influence of water supply, its evaporation, mixing and afterburning of combustion products in oxygen on the air flow structure and gas-dynamic and thermophysical parameters of the jet flow have been revealed;
  • flow in a block jet flow formed as a result of jet flow interaction of a multi-nozzle jet propulsion system. Based on the created software, the research can be conducted to study jet flows in the block jets for propulsion systems of different layouts.


  • mathematical simulations have been formulated, algorithms and software have been created to select and justify the design parameters of branched hydraulic fuel systems of liquid-propellant jet engines control units. This software and methods makes it possible to determine the design parameters taking into account the structural features of the hydraulic paths and hydraulic resistance of the lead pipelines, control and control valves; the degree of gas saturation of the fuel components, the dynamics of electro- or pneumatically controlled valves, thermodynamic processes at the outlet of the system;

The created software and methods are used at “Yuzhnoye” State Design Office to support the bench tryout of liquid-jet system (LJS) of motion control of the 3rd stage space rocket “Cyclone-4”, taking into account gassing and disturbance from the main engine’s work.

The design support and substantiation of the sufficiency of types and amounts of ground bench tryout of motion control of the launch vehicle upper stage motion control system to simulate flight conditions has been performed.

Scientific methods and software of the tryout of technological processes:

The software and methods, created to provide the development and operation of space hardware have been widely used to calculate the substantiation of the parameters of various technological processes: combustion of dry and water-saturated coal particles, flame spraying, heating and cooling of steel in a bell furnace. The effectiveness of methods and software is confirmed by their practical use in the development of new technical objects for various purposes.

  • Dry and water-saturated particles of coal combustion in gas-dispersed flow.

It is indicated that the ignition and burning times of a wet particle are reduced when volumetric temperature changes in a coal particle are taken into account.

  • A set of Two_Phase programs has been created for studying the heating and melting of particles from refractory materials in the gas-dynamic paths of gas-flame spraying devices.

Based on parametric calculations, methods for organizing the process of acceleration, heating and melting of particles from refractory materials (such as zirconium dioxide ZrO2 and tungsten carbide WC), the melting temperature of which reaches 3000 K, are reasonable, which is comparable with the temperature of the products of combustion of high-energy fuels.

  • Scientific and methodological support for the microclimate systems creation has been developed.

Technical proposals and scientific and methodological support for design and calculation work on the creation of a microclimate system for agricultural machines based on low-pressure air vortex tubes, which is characterized by high technical, economic, ergonomic and environmental characteristics. New technical solutions have been proposed for the formation of a rational structure of the system, the type and composition of its units; experimentally substantiated methods of calculation and selection of design, operational and structural parameters of units and system nodes.

Major publications:

  1. Timoshenko V. I. The technology of numerical solution of problems in gas dynamics by using the electronic computer (in Russian) / V. I. Timoshenko, A. V. Limanskiy – Kiev : Naukova dumka, 1985. – 231 p.
  2. Timoshenko V. I. Computer technology of solving problems in gasdinamics / V. I. Timoshenko – New York : Begell house inc. Publishers, 1998. – 247 p.
  3. Timoshenko V. I. The supersonic flows of viscous gas (in Russian) / V. I. Timoshenko – Kiev : Naukova dumka, 1987. – 183 p.
  4. Timoshenko V. I. Gas dynamics of high-temperature technological processes (in Russian) / V. I. Timoshenko – Dnipopetrovsk : ITM of the NASU and NSAU, 2003. – 460 p.
  5. Timoshenko V. I. Theoretical foundations of the technical gas dynamics (in Russian) //Kiev : Naukova dumka, 2013. 426p
  6. Timoshenko V. I. Problems of providing completeness of the methane-containing block-jet combustion in a rocket ramjet engine’s combustion chamber / V. I. Timoshenko, I. S. Belotserkovets, V. P. Gusinin // Acta Astronautica. – 2009. -V.65, ? 9 -10, P. -1231 -1237.
  7. Gorbuntsov V. V., Zavoloka A. N., Sviridenko N. F. Improving the target efficiency for space purpose midrange rocket: promising directions of modernization (in Russian) // Tekhnicheskaya Mekhanika. – 2016. – #4. – Pp. 50-61.
  8. Sviridenko N.F. Calculation and selection of key operating and design parameters of low pressure vortex tube of air refrigerating plant (in Russian) / N. F. Sviridenko, V. S. Senkin, G. I. Ilyin // Tekhnicheskaya Mekhanika. – 2013. – #2. – Pp. 89 – 98.
  9. Ukrainian Patent for Invention No. 102987, IC B 64 C 13/00. Method and control device of perturbed motion of elastically deformed launch vehicle around the center of mass (in Ukrainian) / Gorbuntsov V. V., Zavoloka O. M., Sviridenko M. F.; applicant and patent holder is the Institute of Technical Mechanics of the NASU and SSAU. – U201209134 : applied on 25.07.2012; published on 27.08.2013, Bul. No 16.
  10. Ukrainian Patent for Invention No. 104841, IC F 02 K 9/42. Method and device to ensure the engine operation stability of the launch vehicle with the use of gas-saturated liquid fuel components (in Ukrainian) / Gorbuntsov V. V., Zavoloka O. M., Sviridenko M. F.; applicant and patent holder is the Institute of Technical Mechanics of the NASU and SSAU. – U201209694 : applied on 10.08.2012; published on 11.03.2014, Bul. No 6.
  11. Ukrainian patent for Invention No. 108530, IPC F 02 K 9/42. Method and device to pressurize the boost tank of the launch vehicle with high-temperature gas generated in the interior space / Gorbuntsov V.V., Zavoloka O.M., Sviridenko M.F., Nikolaev O.D., Mitikov Yu.O .; the applicant and patent holder is the Institute of Technical Mechanics of the NASU and SSAU. – a201309278: claimed 07/23/2013; publ. 05/12/2015, Bull. Number 9.
  12. Ukrainian Patent for Invention No. 15309/ZU/14, IC B 64 H 1/00. Plant to regulate the air supplied to the vehicle cabin (in Ukrainian) / Gorbuntsov V. V., Zavoloka O. M., Sviridenko M. F.; applicant and patent holder is the Institute of Technical Mechanics of the NASU and SSAU. – U201404262 : applied on 22.04.2014; published on 24.07.2014, Bul. No 6.
OFFICE ADDRESS:Institute of Technical Mechanics , 15 Leshko-Popelya St., Dnipro, Ukraine, 49005
PHONE NUMBER:+38-056-372-06-41

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