Investigation of the stability of melt flow in gating systems

Niels Skat Tiedje, Per Larsen

Research output: Contribution to journalJournal articleResearchpeer-review

Abstract

Melt flow in four different gating systems designed for production of brake discs was analysed experimentally and by numerical modelling. In the experiments moulds were fitted with glass fronts and melt flow was recorded on video. The video recordings were compared with modelling of melt flow in the gating systems. Particular emphasis was on analysing local pressure and formation of pressure waves in the gating system. It was possible to compare melt flow patterns in experiments directly to modelled flow patterns. Generally there was good agreement between flow patterns and filling times. However description of free liquid surfaces proved to be incorrect in the numerical model. Modelled pressure fields served to explain how specific parts of the gating systems cause instability and are a good tool to describe the quality of a gating system. The results shows clearly that sharp changes in the geometry of the gating system causes pressure waves to form that eventually lead to defective castings. It is clear that sharp corners and dead ends in gating systems should be avoided, and that more stream lined, organic designs based on fluid dynamic principles will are necessary to design gating systems for production of high quality castings.
Original languageEnglish
JournalMetallurgical and Materials Transactions B - Process Metallurgy and Materials Processing Science
Volume42B
Issue number1
Pages (from-to)189-201
ISSN1073-5615
DOIs
Publication statusPublished - 2011

Keywords

  • Experiments
  • Gating System
  • Hydraulic Jump
  • Modelling
  • Melt Flow
  • Casting

Cite this

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title = "Investigation of the stability of melt flow in gating systems",
abstract = "Melt flow in four different gating systems designed for production of brake discs was analysed experimentally and by numerical modelling. In the experiments moulds were fitted with glass fronts and melt flow was recorded on video. The video recordings were compared with modelling of melt flow in the gating systems. Particular emphasis was on analysing local pressure and formation of pressure waves in the gating system. It was possible to compare melt flow patterns in experiments directly to modelled flow patterns. Generally there was good agreement between flow patterns and filling times. However description of free liquid surfaces proved to be incorrect in the numerical model. Modelled pressure fields served to explain how specific parts of the gating systems cause instability and are a good tool to describe the quality of a gating system. The results shows clearly that sharp changes in the geometry of the gating system causes pressure waves to form that eventually lead to defective castings. It is clear that sharp corners and dead ends in gating systems should be avoided, and that more stream lined, organic designs based on fluid dynamic principles will are necessary to design gating systems for production of high quality castings.",
keywords = "Experiments, Gating System, Hydraulic Jump, Modelling, Melt Flow, Casting",
author = "Tiedje, {Niels Skat} and Per Larsen",
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language = "English",
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pages = "189--201",
journal = "Metallurgical and Materials Transactions B - Process Metallurgy and Materials Processing Science",
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}

Investigation of the stability of melt flow in gating systems. / Tiedje, Niels Skat; Larsen, Per.

In: Metallurgical and Materials Transactions B - Process Metallurgy and Materials Processing Science, Vol. 42B, No. 1, 2011, p. 189-201.

Research output: Contribution to journalJournal articleResearchpeer-review

TY - JOUR

T1 - Investigation of the stability of melt flow in gating systems

AU - Tiedje, Niels Skat

AU - Larsen, Per

PY - 2011

Y1 - 2011

N2 - Melt flow in four different gating systems designed for production of brake discs was analysed experimentally and by numerical modelling. In the experiments moulds were fitted with glass fronts and melt flow was recorded on video. The video recordings were compared with modelling of melt flow in the gating systems. Particular emphasis was on analysing local pressure and formation of pressure waves in the gating system. It was possible to compare melt flow patterns in experiments directly to modelled flow patterns. Generally there was good agreement between flow patterns and filling times. However description of free liquid surfaces proved to be incorrect in the numerical model. Modelled pressure fields served to explain how specific parts of the gating systems cause instability and are a good tool to describe the quality of a gating system. The results shows clearly that sharp changes in the geometry of the gating system causes pressure waves to form that eventually lead to defective castings. It is clear that sharp corners and dead ends in gating systems should be avoided, and that more stream lined, organic designs based on fluid dynamic principles will are necessary to design gating systems for production of high quality castings.

AB - Melt flow in four different gating systems designed for production of brake discs was analysed experimentally and by numerical modelling. In the experiments moulds were fitted with glass fronts and melt flow was recorded on video. The video recordings were compared with modelling of melt flow in the gating systems. Particular emphasis was on analysing local pressure and formation of pressure waves in the gating system. It was possible to compare melt flow patterns in experiments directly to modelled flow patterns. Generally there was good agreement between flow patterns and filling times. However description of free liquid surfaces proved to be incorrect in the numerical model. Modelled pressure fields served to explain how specific parts of the gating systems cause instability and are a good tool to describe the quality of a gating system. The results shows clearly that sharp changes in the geometry of the gating system causes pressure waves to form that eventually lead to defective castings. It is clear that sharp corners and dead ends in gating systems should be avoided, and that more stream lined, organic designs based on fluid dynamic principles will are necessary to design gating systems for production of high quality castings.

KW - Experiments

KW - Gating System

KW - Hydraulic Jump

KW - Modelling

KW - Melt Flow

KW - Casting

U2 - 10.1007/s11663-010-9446-5

DO - 10.1007/s11663-010-9446-5

M3 - Journal article

VL - 42B

SP - 189

EP - 201

JO - Metallurgical and Materials Transactions B - Process Metallurgy and Materials Processing Science

JF - Metallurgical and Materials Transactions B - Process Metallurgy and Materials Processing Science

SN - 1073-5615

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