Soviet Mining

, Volume 3, Issue 2, pp 165–168 | Cite as

Signs of rotating aerodynamic breakaway in axial pit ventilator fans

  • A. A. Dzidziguri
  • T. I. Matikashvili
Brief Communications
  • 16 Downloads

Summary

  1. 1.

    In aerodynamic tests on fans, either in test beds with input bends simulating pit installations or in pit conditions, rotating aerodynamic breakaway may cause variations in the fan's output, which can be heard as characteristic changes in the fan noise. These variations are usually very weak, but if there is an accidental resonance in the acoustic system formed by the fan and internal test-bed cavity, they may become stronger and appear similar to “pumpage.”

     
  2. 2.

    This undesirable effect can be avoided by appropriate choice of the test-bed chamber volume or the fan rotation speed. The acoustic mass of the ventilator and the resonance frequency can be calculated from Eqs. (1) and (3).

     
  3. 3.

    Equation (4) for the relative rotation speed of the breakaway zone, derived for axial compresors at the TsAGI[Central Aerodynamics] Institute, also gives good agreement with the experimental results for mine ventilator fans.

     
  4. 4.

    By measuring the pressure in a hole in the fan casing in front of the rotor by means of an inertialess device, we found that there are warning signs of the onset of breakaway, and these can be used in the construction of automatic anti-breakaway devices.

     

Keywords

Pressure Characteristic Pumpage Frequency Acoustic System Explosion Physics Aerodynamic Test 

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

Literature Cited

  1. 1.
    A. A. Dzidziguri and T. L. Matikashvili, Unstable Behavior of Fans and Methods of Preventing It [in Russian], Moscow, Nauka (1965).Google Scholar
  2. 2.
    G. A. Borisov, E. A. Lokshtanov, and L. E. Ol'shtein, Rotating Breakaway in an Axial Compressor, Promyshlennaya Aerodinamika, No. 24 (1962).Google Scholar
  3. 3.
    Specifications for Main Ventilation Fans in Mines for 1962–1965 [in Russian], TsBTI (1962).Google Scholar
  4. 4.
    K. A. Ushakov, I. V. Brusilovskii and A. R. Bushel, Aerodynamics of Axial Fans and Their Constructional Elements [in Russian], Moscow, Gosgortekhizdat (1960).Google Scholar
  5. 5.
    G. S. Samoilovich, Investigation of Transient Phenomena in Axial Compressors, Izv. Vuzov, Mashinostroenie, No. 2 (1960).Google Scholar
  6. 6.
    A. A. Dzidziguri, T. L. Matikashvili, and N. Sh. Durmishidze, Transient Phenomena in Aerodynamic Tests on Ventilator Fans, In Symposium: Mining Mechanics and Ventilation [in Russian], Tbilisi, Izd. AN GSSR (1965).Google Scholar

Copyright information

© Consultants Bureau 1967

Authors and Affiliations

  • A. A. Dzidziguri
  • T. I. Matikashvili

There are no affiliations available

Personalised recommendations