Dynamics of pneumatic system of ejection system for aircraft models
Authors: Brusov V.A., Merzlikin Yu.Yu.
Published in issue: #12(168)/2025
Category: Aviation and Rocket-Space Engineering | Chapter: Design, Construction, Production, Testing, and Operation of Aircraft
When designing and developing a number of modern aircraft, it is necessary to conduct experimental studies of their similar models during an emergency landing on a water surface. Such experimental studies are conducted on a special ejection system, the main element of which is a pneumatic cylinder. A model of the aircraft is suspended from the cylinder rod and launched on water surface. The main characteristic of aircraft model launches is the launch speed or ejection speed, which is determined by the dynamics of the pneumatic system connected to the cylinder. On the other hand, the ejection speed depends on the mass of the aircraft model being studied. To determine the ejection speed of the model during experimental studies, a mathematical model has been developed that describes the dynamics of the pneumatic system and its output element, the pneumatic cylinder. The mathematical model is a system of differential equations that describe the movement of the actuator, taking into account the laws of pressure changes in the cavities of the actuator, friction forces, and external loads. Calculations studies have shown the possibility of obtaining the specified ejection speeds of models when using the chosen scheme of the pneumatic system.
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References
[1] Aviatsionnyye pravila. Ch. 25: Normy letnoy godnosti samoletov transportnoy kategorii [A viation rules. P.25: Airworthiness standards for transport category aircraft]. Moscow, MAK Publ., 1994.
[2] Goncova L.G. Issledovaniya gidrodinamiki vynuzhdennoi posadki letatelnych apparatov na vodu I razrabotka na ich osnove rekomendaciy po vyboru parametrov LA: Avtoref. dis. … kand. tekhn. nauk [Research on the hydrodynamics of forced water landings of aircraft and the development of recommendations for selecting aircraft parameters based on this research. Abstract of Diss. Cand. Sc. (Eng.)]. Moscow, 2004, 25 p.
[3] Goncova L.G., Shorygin O.P., Belyaevskiy A.N. Gydrodinamika avariynoy posadki na vodu sukhoputnykh samoletov [Hydrodynamics of emergency water landings of land-based aircraft.]. In: Collection of Papers of the IV Scientific Conference on Hydroaviation “Hydroaviasalon 2002”. Moscow, TsAGI Publ., 2002, pp. 327–333.
[4] Sereda V.A. Klassifikatsia zakonov raspredelenia tyagovogo usilia puskovykh nazemnykh ustroistv bespilotnykh letatelnykh apparatov [Classification of the laws of thrust distribution of ground-based launchers for unmanned aerial vehicles]. Aerospace Engineering and Technology, 2010, no. 4 (71), pp. 63–66.
[5] McGeer B.T., von Flotow A.H., Roeseler C. Methods and apparatuses for launching unmanned aircraft, including releasably gripping aircraft during launch and breaking subsequent grip motion: United States Patent No. US 7, 165, 745 B2. Date of Patent: Jan. 23, 2007.
[6] Sereda V.A., Avilov I.S. Optimizatsia dinamicheskikh kharakteristik pnevmaticheskogo puskovogo ustroistva bespilotnogo letatelnogo apparata [Optimization of the dynamic characteristics of an unmanned aerial vehicle’s pneumatic launcher]. Aerospace Engineering and Technology, 2010, no. 6 (73), pp. 23–27.
[7] Sereda V.A. Kompleksno-sopryazhennaya model pnevmogidravlicheskogo nazemnogo puskovogo ustroistva bespilotnogo letatelnogo apparata [Complex-coupled model of a pneumohydraulic ground-based launch device for an unmanned aerial vehicle]. In: Open Information and Computer Integrated Technologies, 2011, no. 50, pp. 17–24.
[8] Rakhmatullin Kh.A., Sagomonyan A.Ya., Bunimovich A.I. Gazovaya dimamika [Gas dynamics]. Moscow, Vysshaya Shkola Publ., 1965, 722 p.
[9] Beknev V.S., Epifanov V.M., Leontiev A.I. Gazovaya dimamika [Gas dynamics]. Moscow, BMSTU-Press., 1997, 445 p.
[10] Herz E.V., Krejnin G.V. Raschet pnevmoprivodov [Calculation of pneumatic actuators]. Moscow, Mashinostroenie Publ., 1975, 267 p.
[11] Egorov I.N., Krejnin G.V., Matusov I.B. Mnogokriterialnaya optimizatsiya slozhnykh technicheskikh sistem ot proektirovaniya do upravleniya [Multi-criteria optimization of complex technical systems from design to management]. Journal of Machinery Manufacture and Reliability, 1998, no. 2, pp. 12–18.
[12] Popov D.N. Dinamika i regulirovanie gidro i pnevmosistem [Dynamics and regulation of hydro- and pneumosystems]. Moscow, Mashinostroenie Publ., 1987, 467 p.
[13] Popov D.N. Mechanika gidro- i pnevmoprivodov [Mechanics of hydraulic and pneumatic actuators]. Moscow, BMSTU-Press, 2002, 320 p.
[14] Krivts I.L., Krejnin G.V. Pneumatic actuating systems for automatic equipment. Structure and design. FL, СRS Press, 2006, 343 p.