Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Computational Study of Velocity Distribution for Designing some Gas Quench Chamber and Furnace Ducts
KTH, School of Engineering Sciences (SCI), Mechanics.
KTH, School of Engineering Sciences (SCI), Aeronautical and Vehicle Engineering.
KTH, School of Engineering Sciences (SCI), Centres, Faxén Laboratory.
2005 (English)In: Journal of Materials Processing Technology, ISSN 0924-0136, E-ISSN 1873-4774, Vol. 155, no Part 2 Sp. Iss. SI, 1727-1733 p.Article in journal (Refereed) Published
Abstract [en]

Gas cooled quenching and many other applications require high-speed uniform-velocity flows, with minimal pressure drop. The flow ducting geometry is often rather complex, with flow splitting, 90-180 degrees bends, and circular-to-rectangular cross-section transition ducts (the latter are used, for example, between the circular blower duct and the rectangular quenching baskets). Similar situations exist in forced convection furnaces. To provide design guidance in the choice of such ducts, and focusing primarily on circular-to-rectangular transition ducts. the flow was modelled and computed, and the results were successfully validated. Sensitivity of the velocity uniformity and pressure drop with respect to the primary geometric parameters, pressure, and Reynolds numbers was examined in the range (1.3) 10(5) # Re # (7.8)10(5), with an ultimate objective to produce optimal designs. For a length-to-diameter ratio AL = L/D < 1.0, flow nonuniformity at the exit plane and pressure drop are increased by 33 and 83%, respectively, as the aspect ratio (rectangular duct width-to-height) AR decreases from 4 to 1. Increasing AR beyond 1.5 leads to linearly increasing nonuniformity and pressure drops. A diverging-contracting duct has proven to lead to lesser nonuniformity, while it did not influence the pressure drop. Increasing the inlet pressure from 1 to 20 bar led to a decrease in flow distortion by 11% at the duct exit planes. At atmospheric pressure, increasing the Reynolds number from (1.3)10(5) to (7.8)10(5) increased distortion by 8%. Some preliminary design recommendations for circular-to-rectangular duct transitions are to try and keep AL > 1 and AR < 1.5.

Place, publisher, year, edition, pages
2005. Vol. 155, no Part 2 Sp. Iss. SI, 1727-1733 p.
Keyword [en]
circular-to-rectangular duct transitions, duct flow, duct bends, quench chamber design, velocity uniformity, furnace design
National Category
Computational Mathematics
Identifiers
URN: urn:nbn:se:kth:diva-5203DOI: 10.1016/j.jmatprotec.2004.04.335ISI: 000225845800096Scopus ID: 2-s2.0-10044221822OAI: oai:DiVA.org:kth-5203DiVA: diva2:8019
Note
QC 20101019 QC 20110920Available from: 2005-05-31 Created: 2005-05-31 Last updated: 2017-12-04Bibliographically approved
In thesis
1. CFD in the design of gas quenching furnace
Open this publication in new window or tab >>CFD in the design of gas quenching furnace
2005 (English)Doctoral thesis, comprehensive summary (Other scientific)
Abstract [en]

This thesis focuses on the numerical and theoretical studies of gas quenching in industrial furnaces. Gas quenching is the rapid cooling of metal pieces, aiming at forcing a phase transformation of the metal structure to improve its mechanical properties. The numerical methodology has been evaluated with respect to the desired accuracy and different aspects of the flow with importance for achieving an optimized process have been investigated. Initially, attention was paid to the flow and heat transfer fields both in an empty furnace and in a furnace loaded with different charges with the objective to study the influence of the charge configuration on the flow and heat transfer uniformity. This study led to the identification of several possible improvements, which are currently being implemented by the industrial partners of this project. As earlier studies had shown the importance of flow uniformity on the quality of the heat treatment, the subsequent work focused substantially on the flow uniformity upstream of the quenching zone resulting in design recommendations for the particular type of furnace under consideration. The dependence of the performance of the coolant medium on its composition was investigated theoretically and an analysis of most important parameters was carried out. Improved knowledge of the effect of gas mixture composition on heat transfer was added to the body of knowledge already available.

Place, publisher, year, edition, pages
Stockholm: KTH, 2005. xii, 47 p.
Series
Trita-MEK, ISSN 0348-467X ; 2005:12
Keyword
Numerical analysis, Gas quenching, modeling, CFD, gas mixtures, uniformity., Numerisk analys
National Category
Computational Mathematics
Identifiers
urn:nbn:se:kth:diva-239 (URN)
Public defence
2005-06-16, D2, D, Lindstedsvägen 5, Stockholm, 10:00
Opponent
Supervisors
Note
QC 20101019Available from: 2005-05-31 Created: 2005-05-31 Last updated: 2010-10-19Bibliographically approved

Open Access in DiVA

No full text

Other links

Publisher's full textScopus

Search in DiVA

By author/editor
Macchion, OlivierRizzi, ArthurLior, Noam
By organisation
MechanicsAeronautical and Vehicle EngineeringFaxén Laboratory
In the same journal
Journal of Materials Processing Technology
Computational Mathematics

Search outside of DiVA

GoogleGoogle Scholar

doi
urn-nbn

Altmetric score

doi
urn-nbn
Total: 95 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf