Next Article in Journal
Comparison of Power Requirements: Flapping vs. Fixed Wing Vehicles
Previous Article in Journal
Improved Separation of Tone and Broadband Noise Components from Open Rotor Acoustic Data
Article Menu

Export Article

Open AccessArticle
Aerospace 2016, 3(4), 30; doi:10.3390/aerospace3040030

Numerical Study of Transition of an Annular Lift Fan Aircraft

UAV Research Institute, Northwestern Polytechnical University, 127 West Youyi Road, Xi’an 710072, China
*
Author to whom correspondence should be addressed.
Academic Editor: Robert Spall
Received: 14 August 2016 / Revised: 12 September 2016 / Accepted: 17 September 2016 / Published: 23 September 2016
View Full-Text   |   Download PDF [9954 KB, uploaded 23 September 2016]   |  

Abstract

The present study aimed at studying the transition of annular lift fan aircraft through computational fluid dynamics (CFD) simulations. The oscillations of lift and drag, the optimization for the figure of merit, and the characteristics of drag, yawing, rolling and pitching moments in transition are studied. The results show that a two-stage upper and lower fan lift system can generate oscillations of lift and drag in transition, while a single-stage inner and outer fan lift system can eliminate the oscillations. The characteristics of momentum drag of the single-stage fans in transition are similar to that of the two-stage fans, but with the peak of drag lowered from 0.63 to 0.4 of the aircraft weight. The strategy to start transition from a negative angle of attack −21° further reduces the peak of drag to 0.29 of the weight. The strategy also reduces the peak of pitching torque, which needs upward extra thrusts of 0.39 of the weight to eliminate. The peak of rolling moment in transition needs differential upward thrusts of 0.04 of the weight to eliminate. The requirements for extra thrusts in transition lead to a total thrust–weight ratio of 0.7, which makes the aircraft more efficient for high speed cruise flight (higher than 0.7 Ma). View Full-Text
Keywords: VTOL; annular duct; lift fan; aircraft; transition VTOL; annular duct; lift fan; aircraft; transition
Figures

This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. (CC BY 4.0).

Scifeed alert for new publications

Never miss any articles matching your research from any publisher
  • Get alerts for new papers matching your research
  • Find out the new papers from selected authors
  • Updated daily for 49'000+ journals and 6000+ publishers
  • Define your Scifeed now

SciFeed Share & Cite This Article

MDPI and ACS Style

Jiang, Y.; Zhang, B. Numerical Study of Transition of an Annular Lift Fan Aircraft. Aerospace 2016, 3, 30.

Show more citation formats Show less citations formats

Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Related Articles

Article Metrics

Article Access Statistics

1

Comments

[Return to top]
Aerospace EISSN 2226-4310 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top