Repository logo
  • Log In
    Log in via Symplectic to deposit your publication(s).
Repository logo
  • Communities & Collections
  • Research Outputs
  • Statistics
  • Log In
    Log in via Symplectic to deposit your publication(s).
  1. Home
  2. Faculty of Engineering
  3. Mechanical Engineering
  4. Mechanical Engineering
  5. Electrostatic fields for the control of evaporating charged fuel sprays
 
  • Details
Electrostatic fields for the control of evaporating charged fuel sprays
File(s)
1-s2.0-S0301932222002725-main.pdf (3.8 MB)
Published version
Author(s)
Fredrich, Daniel
Weiand, Erik
Giusti, Andrea
Type
Journal Article
Abstract
The current socio-economic shift towards electrification of the transport sector and development of hybrid thermal–electric propulsion systems provides new opportunities for the development of ‘clean’ aviation technologies. In this work, the use of electrostatic fields to control the location of electrically charged fuel droplets is proposed as a novel technology to enhance pre-evaporation of liquid sprays in confined spaces. An electrospray in cross-flow is numerically investigated using large-eddy simulations for a range of flow and droplet conditions in order to study the feasibility of the approach. A deterministic model is further introduced to compute the trajectory of single droplets in a steady cross-flow. This enables a separation of the effects of turbulence, droplet repulsion and evaporation through comparison with data obtained from the large-eddy simulations, and at the same time provides a cheap computational tool to explore a wider range of operating conditions. It is shown that external electrostatic fields below the breakdown threshold of air can significantly change the trajectory of charged droplets at moderate flow velocities. Moreover, electrostatic forces acting in the opposite direction of the mean cross-flow can potentially be used to stabilise the spray position within a confined region, hence allowing for an increase of the residence time available for full evaporation. The application and modulation of such electrostatic forces is envisioned as a new paradigm to achieve ‘targeted evaporation’ in next-generation hybrid thermal–electric aero-engines and to improve the fuel-oxidiser mixing quality. The electrical power associated with the external electrostatic field to achieve droplet stabilisation is negligible compared to the thermal power released by complete combustion of the injected fuel. In addition, it is shown that stabilisation of the droplets enhances the evaporation rate (by more than 30%) and mixing quality due to an increase of the relative velocity between the droplets and the gas flow, as well as the turbulence induced by the stagnating spray cloud. The results of this work offer new insights for the development of advanced fuel injection strategies based on electrohydrodynamics.
Date Issued
2023-03
Date Acceptance
2022-10-26
Citation
International Journal of Multiphase Flow, 2023, 160, pp.1-8
URI
http://hdl.handle.net/10044/1/101662
URL
https://www.sciencedirect.com/science/article/pii/S0301932222002725?via%3Dihub
DOI
https://www.dx.doi.org/10.1016/j.ijmultiphaseflow.2022.104312
ISSN
0301-9322
Publisher
Elsevier BV
Start Page
1
End Page
8
Journal / Book Title
International Journal of Multiphase Flow
Volume
160
Copyright Statement
© 2022 The Author(s). Published by Elsevier Ltd. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).
License URL
http://creativecommons.org/licenses/by/4.0/
Identifier
https://www.sciencedirect.com/science/article/pii/S0301932222002725?via%3Dihub
Publication Status
Published
Article Number
104312
Date Publish Online
2022-11-02
About
Spiral Depositing with Spiral Publishing with Spiral Symplectic
Contact us
Open access team Report an issue
Other Services
Scholarly Communications Library Services
logo

Imperial College London

South Kensington Campus

London SW7 2AZ, UK

tel: +44 (0)20 7589 5111

Accessibility Modern slavery statement Cookie Policy

Built with DSpace-CRIS software - Extension maintained and optimized by 4Science

  • Cookie settings
  • Privacy policy
  • End User Agreement
  • Send Feedback