A novel method to determine the discharge coefficient of constant section nozzles under compressible dynamic flow conditions

[+] Author and Article Information
Angel Comas

Polytechnic University of Catalonia, Heat Engines Department, Colon 7-11, Terrassa, Spain 08222

Carlos Rio Cano

Polytechnic University of Catalonia, Mechanical Engineering Department, Colon 7-11, Terrassa, Spain 08222

Josep M Bergada

Polytechnic University of Catalonia, Fluid Mechanics Department, Colon 7-11, Terrassa, Spain 08222

1Corresponding author.

ASME doi:10.1115/1.4042374 History: Received April 27, 2018; Revised December 17, 2018


The present paper introduces a novel transient experimental method employed to determine the discharge coefficient of constant section nozzles of small diameters of 1 to 3 mm and with a length/diameter ratio of around one. Flow is considered to be real and compressible; the discharge process was analyzed at relatively high pressures, the fluid used was N2. Based on the experimental data, a generalized expression characterizing the discharge coefficient for nozzles of different diameters, lengths and fluid conditions was developed. In order to check the precision of the analytical equation presented, experimental upstream reservoir pressure decay was compared with the temporal pressure decay obtained using the new analytical equation. Good correlation was achieved for pressure differentials up to 7.6 MPa. Despite the fact that the procedure established can be extended to other gases and nozzle configurations, so far the equation presented to estimate the discharge coefficient, can only be applied to orifices with length to diameter ratios of around one.

Copyright (c) 2018 by ASME
Your Session has timed out. Please sign back in to continue.





Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In