Experimental Validation for Globally Optimized  Tractor-Trailer Base Flaps

Jacob Andrew Freeman; Mark Franklin Reeder; Anna Christine Demoret

doi:doi:10.11648/j.ajtte.20190404.11

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Experimental Validation for Globally Optimized Tractor-Trailer Base Flaps

Jacob Andrew Freeman, Mark Franklin Reeder, Anna Christine Demoret

Published in American Journal of Traffic and Transportation Engineering (Volume 4, Issue 4)

Received: 2 July 2019 Accepted: 25 July 2019 Published: 13 August 2019

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Abstract

Using wind-tunnel testing, this study validates a design that was globally optimized under uncertainty and used computational fluid dynamics. The computational study determined a design for a 3-D tractor-trailer base (back-end) drag-reduction device that reduces the wind-averaged drag coefficient by 41% at 57 mph (92 km/h). The wind-tunnel testing applies the same method of including some uncertainties, such that the design is relatively insensitive to variation in wind speed and direction, elevation, and installation accuracy. The validation testing shows a 20.1% reduction in wind-averaged drag coefficient, or 1.3% better than a non-optimized commercial design, and is conducted on a 1/24-scale model of the simplified tractor trailer at a trailer-width-based Reynolds number (Re_W) of 4.9x10⁵. Test data include both force and pressure measurements on the simplified tractor trailer, as well as pressure measurements on the tunnel wall. Measurements are taken at static side-slip angles to enable wind-averaged calculations. Since the original computations are conducted for a full-scale tractor-trailer at Re_W = 4.4x10⁶, this study does not fully validate the computational design due to the wind tunnel limitations and resulting inability to match the Re_W; however, the results show qualitative and quantitative improvement over the non-optimized design.

Published in	American Journal of Traffic and Transportation Engineering (Volume 4, Issue 4)
DOI	10.11648/j.ajtte.20190404.11
Page(s)	103-117
Creative Commons	This is an Open Access article, distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution and reproduction in any medium or format, provided the original work is properly cited.
Copyright	Copyright © The Author(s), 2019. Published by Science Publishing Group

Keywords

Experimental Validation in Low-Speed Wind Tunnel, Optimization Under Uncertainty, Uncertainty Quantification, Aerodynamic Shape Optimization, Drag Reduction

References

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[5]	Freeman JA, Roy CJ. Provisional Patent, “A Shape-Optimized Base Flap Geometry for Reducing Aerodynamic Drag of Tractor-Trailers,” 2014, US Provisional Patent No. 61/992,970.
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APA Style

Jacob Andrew Freeman, Mark Franklin Reeder, Anna Christine Demoret. (2019). Experimental Validation for Globally Optimized Tractor-Trailer Base Flaps. American Journal of Traffic and Transportation Engineering, 4(4), 103-117. https://doi.org/10.11648/j.ajtte.20190404.11

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ACS Style

Jacob Andrew Freeman; Mark Franklin Reeder; Anna Christine Demoret. Experimental Validation for Globally Optimized Tractor-Trailer Base Flaps. Am. J. Traffic Transp. Eng. 2019, 4(4), 103-117. doi: 10.11648/j.ajtte.20190404.11

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AMA Style

Jacob Andrew Freeman, Mark Franklin Reeder, Anna Christine Demoret. Experimental Validation for Globally Optimized Tractor-Trailer Base Flaps. Am J Traffic Transp Eng. 2019;4(4):103-117. doi: 10.11648/j.ajtte.20190404.11

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@article{10.11648/j.ajtte.20190404.11,
  author = {Jacob Andrew Freeman and Mark Franklin Reeder and Anna Christine Demoret},
  title = {Experimental Validation for Globally Optimized  Tractor-Trailer Base Flaps},
  journal = {American Journal of Traffic and Transportation Engineering},
  volume = {4},
  number = {4},
  pages = {103-117},
  doi = {10.11648/j.ajtte.20190404.11},
  url = {https://doi.org/10.11648/j.ajtte.20190404.11},
  eprint = {https://article.sciencepublishinggroup.com/pdf/10.11648.j.ajtte.20190404.11},
  abstract = {Using wind-tunnel testing, this study validates a design that was globally optimized under uncertainty and used computational fluid dynamics. The computational study determined a design for a 3-D tractor-trailer base (back-end) drag-reduction device that reduces the wind-averaged drag coefficient by 41% at 57 mph (92 km/h). The wind-tunnel testing applies the same method of including some uncertainties, such that the design is relatively insensitive to variation in wind speed and direction, elevation, and installation accuracy. The validation testing shows a 20.1% reduction in wind-averaged drag coefficient, or 1.3% better than a non-optimized commercial design, and is conducted on a 1/24-scale model of the simplified tractor trailer at a trailer-width-based Reynolds number (ReW) of 4.9x105. Test data include both force and pressure measurements on the simplified tractor trailer, as well as pressure measurements on the tunnel wall. Measurements are taken at static side-slip angles to enable wind-averaged calculations. Since the original computations are conducted for a full-scale tractor-trailer at ReW = 4.4x106, this study does not fully validate the computational design due to the wind tunnel limitations and resulting inability to match the ReW; however, the results show qualitative and quantitative improvement over the non-optimized design.},
 year = {2019}
}

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TY  - JOUR
T1  - Experimental Validation for Globally Optimized  Tractor-Trailer Base Flaps
AU  - Jacob Andrew Freeman
AU  - Mark Franklin Reeder
AU  - Anna Christine Demoret
Y1  - 2019/08/13
PY  - 2019
N1  - https://doi.org/10.11648/j.ajtte.20190404.11
DO  - 10.11648/j.ajtte.20190404.11
T2  - American Journal of Traffic and Transportation Engineering
JF  - American Journal of Traffic and Transportation Engineering
JO  - American Journal of Traffic and Transportation Engineering
SP  - 103
EP  - 117
PB  - Science Publishing Group
SN  - 2578-8604
UR  - https://doi.org/10.11648/j.ajtte.20190404.11
AB  - Using wind-tunnel testing, this study validates a design that was globally optimized under uncertainty and used computational fluid dynamics. The computational study determined a design for a 3-D tractor-trailer base (back-end) drag-reduction device that reduces the wind-averaged drag coefficient by 41% at 57 mph (92 km/h). The wind-tunnel testing applies the same method of including some uncertainties, such that the design is relatively insensitive to variation in wind speed and direction, elevation, and installation accuracy. The validation testing shows a 20.1% reduction in wind-averaged drag coefficient, or 1.3% better than a non-optimized commercial design, and is conducted on a 1/24-scale model of the simplified tractor trailer at a trailer-width-based Reynolds number (ReW) of 4.9x105. Test data include both force and pressure measurements on the simplified tractor trailer, as well as pressure measurements on the tunnel wall. Measurements are taken at static side-slip angles to enable wind-averaged calculations. Since the original computations are conducted for a full-scale tractor-trailer at ReW = 4.4x106, this study does not fully validate the computational design due to the wind tunnel limitations and resulting inability to match the ReW; however, the results show qualitative and quantitative improvement over the non-optimized design.
VL  - 4
IS  - 4
ER  -

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Author Information

Jacob Andrew Freeman

Department of Aeronautics and Astronautics, Air Force Institute of Technology, Wright-Patterson Air Force Base, Ohio, USA
Mark Franklin Reeder

Department of Aeronautics and Astronautics, Air Force Institute of Technology, Wright-Patterson Air Force Base, Ohio, USA
Anna Christine Demoret

Department of Aeronautics and Astronautics, Air Force Institute of Technology, Wright-Patterson Air Force Base, Ohio, USA

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Plain Text BibTeX RIS

APA Style

Jacob Andrew Freeman, Mark Franklin Reeder, Anna Christine Demoret. (2019). Experimental Validation for Globally Optimized Tractor-Trailer Base Flaps. American Journal of Traffic and Transportation Engineering, 4(4), 103-117. https://doi.org/10.11648/j.ajtte.20190404.11

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ACS Style

Jacob Andrew Freeman; Mark Franklin Reeder; Anna Christine Demoret. Experimental Validation for Globally Optimized Tractor-Trailer Base Flaps. Am. J. Traffic Transp. Eng. 2019, 4(4), 103-117. doi: 10.11648/j.ajtte.20190404.11

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AMA Style

Jacob Andrew Freeman, Mark Franklin Reeder, Anna Christine Demoret. Experimental Validation for Globally Optimized Tractor-Trailer Base Flaps. Am J Traffic Transp Eng. 2019;4(4):103-117. doi: 10.11648/j.ajtte.20190404.11

Copy | Download

@article{10.11648/j.ajtte.20190404.11,
  author = {Jacob Andrew Freeman and Mark Franklin Reeder and Anna Christine Demoret},
  title = {Experimental Validation for Globally Optimized  Tractor-Trailer Base Flaps},
  journal = {American Journal of Traffic and Transportation Engineering},
  volume = {4},
  number = {4},
  pages = {103-117},
  doi = {10.11648/j.ajtte.20190404.11},
  url = {https://doi.org/10.11648/j.ajtte.20190404.11},
  eprint = {https://article.sciencepublishinggroup.com/pdf/10.11648.j.ajtte.20190404.11},
  abstract = {Using wind-tunnel testing, this study validates a design that was globally optimized under uncertainty and used computational fluid dynamics. The computational study determined a design for a 3-D tractor-trailer base (back-end) drag-reduction device that reduces the wind-averaged drag coefficient by 41% at 57 mph (92 km/h). The wind-tunnel testing applies the same method of including some uncertainties, such that the design is relatively insensitive to variation in wind speed and direction, elevation, and installation accuracy. The validation testing shows a 20.1% reduction in wind-averaged drag coefficient, or 1.3% better than a non-optimized commercial design, and is conducted on a 1/24-scale model of the simplified tractor trailer at a trailer-width-based Reynolds number (ReW) of 4.9x105. Test data include both force and pressure measurements on the simplified tractor trailer, as well as pressure measurements on the tunnel wall. Measurements are taken at static side-slip angles to enable wind-averaged calculations. Since the original computations are conducted for a full-scale tractor-trailer at ReW = 4.4x106, this study does not fully validate the computational design due to the wind tunnel limitations and resulting inability to match the ReW; however, the results show qualitative and quantitative improvement over the non-optimized design.},
 year = {2019}
}

Copy | Download

TY  - JOUR
T1  - Experimental Validation for Globally Optimized  Tractor-Trailer Base Flaps
AU  - Jacob Andrew Freeman
AU  - Mark Franklin Reeder
AU  - Anna Christine Demoret
Y1  - 2019/08/13
PY  - 2019
N1  - https://doi.org/10.11648/j.ajtte.20190404.11
DO  - 10.11648/j.ajtte.20190404.11
T2  - American Journal of Traffic and Transportation Engineering
JF  - American Journal of Traffic and Transportation Engineering
JO  - American Journal of Traffic and Transportation Engineering
SP  - 103
EP  - 117
PB  - Science Publishing Group
SN  - 2578-8604
UR  - https://doi.org/10.11648/j.ajtte.20190404.11
AB  - Using wind-tunnel testing, this study validates a design that was globally optimized under uncertainty and used computational fluid dynamics. The computational study determined a design for a 3-D tractor-trailer base (back-end) drag-reduction device that reduces the wind-averaged drag coefficient by 41% at 57 mph (92 km/h). The wind-tunnel testing applies the same method of including some uncertainties, such that the design is relatively insensitive to variation in wind speed and direction, elevation, and installation accuracy. The validation testing shows a 20.1% reduction in wind-averaged drag coefficient, or 1.3% better than a non-optimized commercial design, and is conducted on a 1/24-scale model of the simplified tractor trailer at a trailer-width-based Reynolds number (ReW) of 4.9x105. Test data include both force and pressure measurements on the simplified tractor trailer, as well as pressure measurements on the tunnel wall. Measurements are taken at static side-slip angles to enable wind-averaged calculations. Since the original computations are conducted for a full-scale tractor-trailer at ReW = 4.4x106, this study does not fully validate the computational design due to the wind tunnel limitations and resulting inability to match the ReW; however, the results show qualitative and quantitative improvement over the non-optimized design.
VL  - 4
IS  - 4
ER  -

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