Publication detail

Selection of model liquid with refractive index matching for visualization of internal flow in a scaled atomizer model

SAPÍK, M. MALÝ, M. JEDELSKÝ, J. WIGLEY, G. CEJPEK, O.

Original Title

Selection of model liquid with refractive index matching for visualization of internal flow in a scaled atomizer model

English Title

Selection of model liquid with refractive index matching for visualization of internal flow in a scaled atomizer model

Type

conference paper

Language

en

Original Abstract

A scaled transparent modular model of pressure-swirl (PS) atomizer was prepared from cast PMMA (Poly(methyl methacrylate), Perspex™, Plexiglas™) with the aim to achieve a better understanding of internal flow and subsequent spray formation. Because of use of high-speed imaging and Laser Doppler Anemometry (LDA) the working liquid had to be selected with respect of a refractive index matching (RIM) with the atomizer material. The liquid should be colourless and chemically non-aggressive to the model material with suitable viscosity to achieve the Reynolds number of the internal flow of the original atomizer. Froude number should be high enough to neglect the influence of gravity on the flow. An extensive search for transparent liquids and materials of enlarged models was made with a focus on RIM in performed experiments. Several liquids were chosen, and their chemical effect on PMMA was tested. Despite the successful tests that proved the liquid suit the case, the model material was damaged and the tests proved to be insufficient. For this reason, the tests were modified to better involve the stress of the bolted model. It turned out that a force effect (bolt in the thread, pre-stressed bolt connection) on the material has a significant influence on the acceleration of the chemical effect. The internal flow was examined using a high-speed camera with several liquids.

English abstract

A scaled transparent modular model of pressure-swirl (PS) atomizer was prepared from cast PMMA (Poly(methyl methacrylate), Perspex™, Plexiglas™) with the aim to achieve a better understanding of internal flow and subsequent spray formation. Because of use of high-speed imaging and Laser Doppler Anemometry (LDA) the working liquid had to be selected with respect of a refractive index matching (RIM) with the atomizer material. The liquid should be colourless and chemically non-aggressive to the model material with suitable viscosity to achieve the Reynolds number of the internal flow of the original atomizer. Froude number should be high enough to neglect the influence of gravity on the flow. An extensive search for transparent liquids and materials of enlarged models was made with a focus on RIM in performed experiments. Several liquids were chosen, and their chemical effect on PMMA was tested. Despite the successful tests that proved the liquid suit the case, the model material was damaged and the tests proved to be insufficient. For this reason, the tests were modified to better involve the stress of the bolted model. It turned out that a force effect (bolt in the thread, pre-stressed bolt connection) on the material has a significant influence on the acceleration of the chemical effect. The internal flow was examined using a high-speed camera with several liquids.

Keywords

Atomization, Nozzle, PMMA, Refractive Index

Released

28.06.2019

Publisher

EDP Sciences

Pages from

1

Pages to

6

Pages count

6

URL

Full text in the Digital Library

Documents

BibTex


@inproceedings{BUT151981,
  author="Marcel {Sapík} and Milan {Malý} and Jan {Jedelský} and Graham {Wigley} and Ondřej {Cejpek}",
  title="Selection of model liquid with refractive index matching for visualization of internal flow in a scaled atomizer model",
  annote="A scaled transparent modular model of pressure-swirl (PS) atomizer was prepared from cast PMMA (Poly(methyl methacrylate), Perspex™, Plexiglas™) with the aim to achieve a better understanding of internal flow and subsequent spray formation. Because of use of high-speed imaging and Laser Doppler Anemometry (LDA) the working liquid had to be selected with respect of a refractive index matching (RIM) with the atomizer material. The liquid should be colourless and chemically non-aggressive to the model material with suitable viscosity to achieve the Reynolds number of the internal flow of the original atomizer. Froude number should be high enough to neglect the influence of gravity on the flow. An extensive search for transparent liquids and materials of enlarged models was made with a focus on RIM in performed experiments. Several liquids were chosen, and their chemical effect on PMMA was tested. Despite the successful tests that proved the liquid suit the case, the model material was damaged and the tests proved to be insufficient. For this reason, the tests were modified to better involve the stress of the bolted model. It turned out that a force effect (bolt in the thread, pre-stressed bolt connection) on the material has a significant influence on the acceleration of the chemical effect. The internal flow was examined using a high-speed camera with several liquids.",
  address="EDP Sciences",
  booktitle="EXPERIMENTAL FLUID MECHANICS 2018 (EFM18)",
  chapter="151981",
  doi="10.1051/epjconf/201921302070",
  howpublished="online",
  institution="EDP Sciences",
  number="1",
  year="2019",
  month="june",
  pages="1--6",
  publisher="EDP Sciences",
  type="conference paper"
}