Warm up of an automotive catalyst substrate by pulsating flow: a single channel modelling approach

Stephen F. Benjamin, Carol A. Roberts

Research output: Contribution to journalArticle

10 Citations (Scopus)

Abstract

Rapid warm up of an automotive catalyst substrate is important for early light off. This work considers the results from a model of warm up in a single channel. The mass flow is pulsating with high amplitude, about 75% of mean flow, but without flow reversal. The flow regime is laminar within the channel. Pulsations occur with frequency in the range 16–100 Hz, and are important in close-coupled systems where the catalyst is located near to the engine and where the rate of rise of gas inlet temperature with time is rapid, about 15 K/s. The use of a single channel model with conjugate heat transfer enables the heat transfer coefficient to be evaluated and compared with results from steady flow simulations. The value of the augmentation factor based on heat flux is found to be less than unity. The value of the augmentation factor based on heat transfer coefficient depends on the method for calculating the mean heat transfer coefficient, but is generally less than unity. The changes caused by pulsations will be small in practical systems. Changes in wall temperature found in the simulations are the result of the cumulative effect of changes in the mass flow rate.
Original languageEnglish
Pages (from-to)717–726
JournalInternational Journal of Heat and Fluid Flow
Volume21
Issue number6
DOIs
Publication statusPublished - 2000

Fingerprint

unsteady flow
heat transfer coefficients
Heat transfer coefficients
catalysts
Catalysts
unity
Substrates
inlet temperature
augmentation
mass flow rate
mass flow
wall temperature
Flow simulation
steady flow
Steady flow
gas temperature
engines
Heat flux
heat flux
simulation

Bibliographical note

The full text of this item is not available from the repository.

Keywords

  • modelling
  • single channel
  • automotive catalyst
  • heat transfer
  • warm up
  • pulsating flow

Cite this

Warm up of an automotive catalyst substrate by pulsating flow: a single channel modelling approach. / Benjamin, Stephen F.; Roberts, Carol A.

In: International Journal of Heat and Fluid Flow, Vol. 21, No. 6, 2000, p. 717–726.

Research output: Contribution to journalArticle

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