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Desenfans, Philip: Aerodynamics of the Maple Seed. Project. Hamburg : Aircraft Design and Systems Group (AERO), Department of Automotive and Aeronautical Engineering, Hamburg University of Applied Sciences, 2019. URN: https://nbn-resolving.org/urn:nbn:de:gbv:18302-aero2019-06-01.016

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To cite the version in the repository, please use this identifier: https://doi.org/10.15488/9373

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Sum total of downloads: 899




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Purpose - The paper presents a theoretical framework that describes the aerodynamics of a falling maple (Acer pseudoplatanus) seed. --- Methodology - A semi-empirical method is developed that provides a ratio stating how much longer a seed falls in air compared to freefall. The generated lift is calculated by evaluating the integral of two-dimensional airfoil elements using a preliminary falling speed. This allows for the calculation of the definitive falling speed using Blade Element Momentum Theory (BEMT); hereafter, the fall duration in air and in freefall are obtained. Furthermore, the input-variables of the calculation of lift are transformed to require only the length and width of the maple seed. Lastly, the method is applied to two calculation examples as a means of validation. --- Findings - The two example calculations gave percentual errors of 5.5% and 3.7% for the falling speed when compared to measured values. The averaged result is that a maple seed falls 9.9 times longer in air when released from 20 m; however, this result is highly dependent on geo-metrical parameters which can be accounted for using the constructed method. --- Research limitations - Firstly, the coefficient of lift is unknown for the shape of a maple seed. Secondly, the approximated transient state is yet to be verified by measurement. --- Originality / Value - The added value of this report lies in the reduction of simplifications compared to BEMT approaches. In this way a large amount of accuracy is achieved due to the inclusion of many geometrical parameters, even though simplicity is maintained. This has been accomplished through constructing a simple three-step method that is fundamental and essen-tially non-iterative.
License of this version: CC BY-NC-SA 4.0 Unported
Document Type: Book
Publishing status: publishedVersion
Issue Date: 2019
Appears in Collections:Fakultät für Maschinenbau

distribution of downloads over the selected time period:

downloads by country:

pos. country downloads
total perc.
1 image of flag of United States United States 235 26.14%
2 image of flag of Germany Germany 153 17.02%
3 image of flag of United Kingdom United Kingdom 65 7.23%
4 image of flag of India India 61 6.79%
5 image of flag of Korea, Republic of Korea, Republic of 36 4.00%
6 image of flag of Turkey Turkey 29 3.23%
7 image of flag of France France 21 2.34%
8 image of flag of No geo information available No geo information available 20 2.22%
9 image of flag of Chile Chile 20 2.22%
10 image of flag of China China 19 2.11%
    other countries 240 26.70%

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