Pneumatic actuators with "bouncing" air-jet - part 2: Flow field in the cascade

• Autorzy: Tesar V. , Peszyński K.
• Języki publikacji: EN

Abstrakty

EN

Unusual actuators generating a fluid force action on a small body by issuing an air jet "reflecting" or "bounding back" from an impact on a wall were described in previous publication (Tesar and Peszynski, 2010). The seemingly impossible return from the wall is based on the unusual effect of the wall provided with perforations that allow a part of the jet to pass through. Upon the impingement, the jet is split in two parts, both having to change their directions. It is the part that remains above the wall, the "reflected" jet, that is of interest for the actuation. In particular, the phenomenon was used in shuttle-less loom to prevent the inserted weft from contact with the reed. The details of the flowfield inside the reed - or cascade of foils with passages between them play a critical role in the phenomenon. This was investigated by flow visualisation discussed in the second part of the paper.

Słowa kluczowe

EN

jet; impinging jet; momentum balance; flow visualisation

PL

bilans pędu; wizualizacja przepływu

• Wydawca: Oficyna Wydawnicza Uniwersytetu Zielonogórskiego
• Czasopismo: International Journal of Applied Mechanics and Engineering
• Rocznik: 2010
• Tom: Vol. 15, no 3
• Strony: 867--874
• Opis fizyczny: Bibliogr. 10 poz., rys., wykr.

Twórcy

autor

Tesar V.

autor

Peszyński K.

• Institute of Thermomechanics Academy of Sciences of the Czech Republic Prague, CZECH REPUBLIC,

Bibliografia

• Adanur S. (2000): Handbook of weaving. – Textile Institute, Manchester, ISBN: 1587160137.
• Scholz N. (1965): Aerodynamik der Schauffelgitter. – (Aerodynamcs of Cascades - in German), Braun, Karlsruhe.
• Talukdar M.K., Sriramulu P.K. and Ajgaonkar D.B. (2004): Weaving Machines, Mechanisms, Management. – Mahajan Publishers, Ahmedabad, India, ISBN: 8185401160.
• Tesař V. (1990): “Reflection” of a fluid jet from a (perforated) wall: A flow visualization study. – New York: Flow Visualization V, editor R. Řezníček, Hemisphere Publ. Co., ISSN 0-89116-887-7.
• Tesař V. (1994): Aerodynamic investigations of the weaving reed. – Proc. of WORKSHOP ČVUT 94, Part A, section Fluid Mechanics, Prague, Czech Republic, pp.167.
• Tesař V. (1995): Two-equation turbulence model solution of the plane turbulent jet. – Acta Polytechnica, vol. 35, No.2, pp.19.
• Tesař V. (2001): Reynolds-number dependent flow turning by a fixed cascade. – Proc. of RECURKULACJA - Proc. of XI. International Conference, ISSN 0137-9682, Bydgoszcz, Poland. pp.265.
• Tesař V (2009) Odraz proudu od paprsku. – (Jet Bouncing from Weaving Reed. – in Czech), Conf. Topical Problems of Fluid Mechanics, Prague, Czech Republic, Institute of Thermomechanics AS ČR, v. v. i. ( editors: Příhoda, J.; Kozel, K.), ISBN 978-80-87012-19-2, pp.103-106.
• Tesař V. and Peszynski K. (2010), Pneumatic Actuators with “Bouncing” Air Jet, Part I: Numerical solutions. – Int. J. of Applied Mechanics and Engineering, in Print.
• Tollmien W. (1926): Berechnung Turbulenter Ausbreitungsvorgänge. – Zetschrift für Angewandte Mathematik und Mechanik, Bd.6, Berlin, Germany, p.68.