Industrial projects
Spacecraft engineering [top]
I faced with really challenging projects working with Moscow Aviation Institute. We designed some unique aircraft and spacecraft structures. One of them is sketched below
Usually the fuel is pushed out from the tank by gas pressure. But sometimes the fuel and gas are mixed by dynamics and vibration, especially in the weightless state. To avoid this situation and to separate gas and fuel in the spherical container a new bladder has been created, which was an inversing thin semi-spherical shell under uniform external pressure. The deflection of the shell reached two radiuses of the sphere at the end of the process. The main goal of this design was to provide shell with a given load-displacement diagram and to estimate stress states of this structure.
Another challenging project I participated in at the Moscow Aviation Institute was devoted to studying composite shells under impulsive and acoustic load of high energy.
Civil engineering [top]
Working for years with Dnepropetrovsk Civil Engineering Academy and State University, I participated and managed the following civil and mechanical engineering projects:
  • simulation of metallic oil tanks with corrosion and damages and design of the tank reinforcements
  • investigation of vibrations and stress analysis of concrete plates of a vessel
  • designing a nonlinear damper of vibrations for vehicles featuring reversing thin shells
  • transient response analysis of biodynamic systems and design of special tools for protection of vehicle driver against impact load
Energy absorber for vehicles [top]
Elastic shell structures can be used for design of energy or shock absorbers. The following two figures show the main idea of such a shock absorber. A typical nonlinear force-displacement diagram explains the behavior of it. Energy is absorbed by loading and then unloading the structure (path ABCDEF).
The second figure illustrates the corresponding device, which contains horizontal rigid element, vertical spring and shell of revolution. I am working on the investigation of this structure using asymptotic formulae and on creation of a software for calculation of deflections, energy absorbed and stresses arising in the shell during the cycle of loading.
The result of investigation was published in the International Journal of Vehicle Design, Vol. 34, No 4, pp399-410, 2004: Evkin A, “Asymptotic investigation of vehicle shock absorber with reversing shell of revolution.”
Current project [top]
In 2002 I decided to combine my experience in programming, research, engineering, and teaching establishing my own company “Software for structures”. The company is a software development, research and consulting firm. This is my part time job in edition to teaching math and doing research in the university of Saudi Arabia. Our software goal is to have a website where structural engineers and analysts, educators, and students can find a collection of powerful, useful, and easy to use online calculations and models. Our specialty is analysis of structures: beams, trusses, plates and shells. Our programs include the disciplines of civil, mechanical, spacecraft, aviation, chemical engineering; and science. We provide solutions to very common problems like bending of beams and plates, stress analysis of trusses, as well as complicated problems of nonlinear behavior and stability of thin shells. In our calculations we use the typical methods for simple structures (beams and trusses) providing the clients with all main steps of the solution, which is especially helpful for student training. For solving complex problems, for instance problems of nonlinear shell theory, we apply our know-how approaches based on our previous research. We also provide a very powerful data fitting calculation, whose result is represented by graphs and simple-to-use formulas. The web site will be released soon.