A METHOD OF ACCOUNTING FOR THE COMPRESSIBILITY OF AIR IN CALCULATING THE FLOW ELEMENTS OF PNEUMATIC INSTRUMENTS,

Abstract

A new form of Bernoulli's equation is proposed to account for the compressibility of a gas with any degree of accuracy in designing the flow elements of pneumatic devices. The compressibility is given in fractions of the velocity head expressed in terms of dimensionless compressibility ratios. The proposed form of the equation may also be used to account for hydraulic resistances in the flow elements and to determine the effect of compressibility and hydraulic drag on gas pressures and velocities. Both elements in which the flow undergoes sudden expansion and those in which the gas is suddenly constricted are considered. When the proposed form of Bernoulli's equation is used, the effect of correcting for accuracy is always less than when the special form of the equation corresponding to 'zero' input velocity of the flow is used.

Document Details

Document Type
Technical Report
Publication Date
Sep 08, 1969
Accession Number
AD0696228

Entities

People

  • O. B. Balakshin

Organizations

  • National Air and Space Intelligence Center

Tags

DTIC Thesaurus Topics

  • Accounting
  • Accuracy
  • Automation
  • Compressive Properties
  • Equations
  • Physical Properties
  • Pneumatic Equipment
  • Precision
  • Resistance

Readers

  • Finite Element Method (FEM) for solving Partial Differential Equations (PDEs)
  • Fluid Mechanics and Fluid Dynamics.
  • Systems Analysis and Design