Achievements

The main goals of the researches are:

  • experimental and theoretical study of all processes and events, occurring during work of the parachute systems of various structure and in different conditions;
  • development, based on these studies, of wide range of mathematic models of parachute system operation, which have various degree of complexity and which allow to conduct deep numeric researches of the operation as well as multiple-choice computations on the design and tests stages;
  • extension of means and methods of experimental studies of parachute systems’ operation and conduction of their tests;
  • extension of range of problems, which can be solved by parachute equipment via increase of its resolution ability on the different parameters of the technical requirements.

Aerodynamics of the parachute systems

The principally new approach to understanding of the interaction of parachute and environment, in which it operates (atmosphere, aqueous media), has been worked out. The interaction should be considered as aeroelastic or hydroelastic process. This approach is now used in development of complex mathematic models, intended for numeric studies of parachute operation on computers.should be considered as aeroelastic or hydroelastic process. This approach is used now in development of complex mathematic models, intended for numeric studies of parachute operation on computers.

All aerodynamic properties of main types of the neutral parachutes, necessary for computation of dynamics of the system “payload-parachute”, are studied for subsonic velocities. The maximum aerodynamic load, occurring during the parachute inflation, and phase of inflation, when it (load) applies, have been studied. Their dependence on area and other parameters of parachute structure as well as on object mass and its trajectory parameters in the moment of the beginning of inflation has been obtained. Besides, the current load on the parachute during all inflation process can be now calculated. The reluctance properties of cluster parachutes and particular features of their inflation have been studied. L/D ratio and other aerodynamic properties are studied for different types of gliding parachute structures. The method of computation of aerodynamic heating of the parachutes on supersonic velocities has been created, it allows to estimate influence of main structural parameters and conditions of deployment on maximal temperature of the parachute material heating. The advanced researches of aerodynamic properties, aeroballistic heating and existence period of various types of models of the parachutes, working on hypersonic velocities (up to Mach number equal to 13).
For parachutes, intended for landing of vehicles in Martian atmosphere (Mach number equal to 4-5), the computational analysis of aerodynamic heating and operability in given modes has been conducted and the recommendations for choice of structural parameters have been given. On the basis of the stated results the methodics have been developed for aerodynamic computation of parachutes of various structure and various purposes.

Parachute systems’ dynamics

So far it has been discovered, that computation of dynamics of putting into operation of the parachute system elements should be conducted on the basis of variable-mass mechanics, oscillation theory and wave dynamics. In the field of dynamics of the system “payload-parachute” it has been discovered that this dynamics is not specified only by aerodynamic, mass, balancing and inertial properties of the object and the parachute. The flexibility of parachute canopy links with the object and their structure significantly affects dynamics. So during mathematic models the system “payload-parachute” should be considered as a system with 12 degrees of freedom. On the basis of these results various methodics and programs, ensuring dynamic computation of parachute system, have been created.

Parachute systems’ strength

The following general statements of computation for strength of any textile element of the parachute system have been worked out:
  • the average workload affecting the element is determined either by methods of strength of materials or by computation of stress-stained state of structure, in which this element is located;
  • strength of the element is obtained taking into account all its work wastes before application of load to the element;
  • safety coefficient is obtained depending on dispersion of load on the element and required reliability for strength.

The corresponding computation methodics and strength standards have been created for practical implementation of these statements relating to parachute systems of various structure and various purposes.

Parachute systems reliability

The methodics of computational estimation of the reliability of the parachute system on functioning and strength and their confirmation by forced tests have been developed. The various methods have been created for the accelerated tests of the parachute system on strength and functioning in stand and flight conditions. The regular analysis of the results of the serial parachute systems usage is organized, it provides feedback between usage and development and its purpose is perfection of parachute systems as well as improvement of their usage conditions.

Joint stock company "Scientific and research institute of parachute design and production" (JSC "NII parachutostroyeniya")
107241, Russian Federation, Moscow, Irkutskaya str., 2 Phone: +7 (495) 462-13-19 Fax: +7 (495) 462-52-33