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LUND UNIVERSITY LIBRARIES

Teoretisk verifiering av kubisk blandningstank

Sjöholm, Mikael (2007) MMK820
Innovation
Abstract
The purpose of this work has been to perform numerical calculations on the cubical
mixing tank the QB mixer, to be able to verify its strength and try to improve it. The
QB mixer is produced by the company QB FoodTech AB.
Firstly a CAD model was made from drawings of the mixer. Then the structure was
analysed in aspects of pressure load, thermal loads and gravitational load. A modal
analysis to get the natural frequencies was also made. All the analyses were
performed in a FEM-program. The results of the analysis of the pressure load was
verified using strain gauge technique. Unfortunately there was no opportunity to
verify the thermal loads. Since some simplifications and limitations were made, the
results of the thermal loads... (More)
The purpose of this work has been to perform numerical calculations on the cubical
mixing tank the QB mixer, to be able to verify its strength and try to improve it. The
QB mixer is produced by the company QB FoodTech AB.
Firstly a CAD model was made from drawings of the mixer. Then the structure was
analysed in aspects of pressure load, thermal loads and gravitational load. A modal
analysis to get the natural frequencies was also made. All the analyses were
performed in a FEM-program. The results of the analysis of the pressure load was
verified using strain gauge technique. Unfortunately there was no opportunity to
verify the thermal loads. Since some simplifications and limitations were made, the
results of the thermal loads are not totally reliable.
Based on the results from the analysis of the actual design some changes were
analysed in a similar way. A strengthening system around the cylinder was added, the
position of the legs moved and the plate thicknesses of some parts were altered in
order to make the design lighter. Two types of strengthening systems were tested, one
circular and one hexagon shaped. Also rounds were added that makes the
strengthening beams follow the contour of the inner tank. This meant to eliminate
stress concentrations there.
The results showed that most of the changes improved the mixer in different ways.
Some eliminated high stresses and some decreased the weight with allowable stress
levels. The thickness of the sheet metal of the inner tank and the thickness of the
strengthening beams should probably be maintained though. It did not matter which
type of strengthening system around the cylinder was used, cylindrical or hexagon
shaped, the cheapest to produce should be chosen.
Since some simplifications were made one should be careful using especially the
thermal results of this thesis. To get more exact thermal results one should use a CFD
program to be able to analyze the heat flow processes more thoroughly. Before this is
done one can try to verify the thermal analysis with strain gauge technique though. (Less)
Please use this url to cite or link to this publication:
author
Sjöholm, Mikael
supervisor
organization
course
MMK820
year
type
H2 - Master's Degree (Two Years)
subject
keywords
mixer, tank, cubical, strain gauge, design analysis
language
English
id
1502700
date added to LUP
2009-11-24 15:35:08
date last changed
2010-02-01 14:40:04
@misc{1502700,
  abstract     = {{The purpose of this work has been to perform numerical calculations on the cubical
mixing tank the QB mixer, to be able to verify its strength and try to improve it. The
QB mixer is produced by the company QB FoodTech AB.
Firstly a CAD model was made from drawings of the mixer. Then the structure was
analysed in aspects of pressure load, thermal loads and gravitational load. A modal
analysis to get the natural frequencies was also made. All the analyses were
performed in a FEM-program. The results of the analysis of the pressure load was
verified using strain gauge technique. Unfortunately there was no opportunity to
verify the thermal loads. Since some simplifications and limitations were made, the
results of the thermal loads are not totally reliable.
Based on the results from the analysis of the actual design some changes were
analysed in a similar way. A strengthening system around the cylinder was added, the
position of the legs moved and the plate thicknesses of some parts were altered in
order to make the design lighter. Two types of strengthening systems were tested, one
circular and one hexagon shaped. Also rounds were added that makes the
strengthening beams follow the contour of the inner tank. This meant to eliminate
stress concentrations there.
The results showed that most of the changes improved the mixer in different ways.
Some eliminated high stresses and some decreased the weight with allowable stress
levels. The thickness of the sheet metal of the inner tank and the thickness of the
strengthening beams should probably be maintained though. It did not matter which
type of strengthening system around the cylinder was used, cylindrical or hexagon
shaped, the cheapest to produce should be chosen.
Since some simplifications were made one should be careful using especially the
thermal results of this thesis. To get more exact thermal results one should use a CFD
program to be able to analyze the heat flow processes more thoroughly. Before this is
done one can try to verify the thermal analysis with strain gauge technique though.}},
  author       = {{Sjöholm, Mikael}},
  language     = {{eng}},
  note         = {{Student Paper}},
  title        = {{Teoretisk verifiering av kubisk blandningstank}},
  year         = {{2007}},
}