Experimental Study of Turbulent Mixing and Selectivity of Competing Reactions

Abstract

Many industrial chemical reactors are inherently limited by imperfect mixing. The flow fields of such reactors are so complex that traditional turbulence models based on the Navier-Stokes and component continuity equations are impractical, particularly when complex reactions are involved. This work evaluates five mechanistic models of mixing and chemical reaction in terms of their ability to predict the selectivity of competing reactions. Experiments were conducted in a highly segregated but well characterized turbulent plug flow reactor to obtain data for competing reactions. The azo-coupling of 1-naphthol with diazotised sulfanilic acid (Bourne reactions) was used as the reaction system. Concentration of reaction products was measured by absorption spectrophotometry with a fiber-optic probe. Turbulence measurements in the reactor were obtained with a pulsed Doppler Ultrasound Velocimeter. These measurements indicated that the mean velocity profile was nearly flat and the turbulence nearly homogeneous. Mechanistic Models with a Turbulence Analogy; Coalescence-Redispersion Model; Slab Diffusion and Related Models; Interaction by Exchange with the Mean Model; The Three Environment Model; and The Four- Environment Model.

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Document Details

Document Type
Technical Report
Publication Date
Jul 01, 1988
Accession Number
ADA197775

Entities

People

  • Rajendrakumar V. Mehta

Organizations

  • Pennsylvania State University

Tags

Communities of Interest

  • Biomedical
  • Energy and Power Technologies
  • Ground and Sea Platforms
  • Weapons Technologies

DTIC Thesaurus Topics

  • Boundary Layer
  • Chemical Engineering
  • Chemical Reactions
  • Chemical Reactors
  • Chemistry
  • Computational Fluid Dynamics
  • Computational Science
  • Continuous Chemical Reactors
  • Differential Equations
  • Doppler Effect
  • Flow Fields
  • Fluid Flow
  • Fluid Mechanics
  • Measurement
  • Mixing
  • Turbulent Flow
  • Turbulent Mixing

Fields of Study

  • Environmental science

Readers

  • Fluid Mechanics and Fluid Dynamics.
  • Organic Chemistry
  • Systems Analysis and Design