The effects of air channel construction and design elements on heat transfer characteristics of bicycle helmets for commuters
(2015) 4th International Cycling Safety Conference- Abstract
- The earlier studies in this measurement series defined the limits and aims for design process to create better ventilating helmets [1], and tested the insulation [2] and evaporative characteristics [3] of the designed mock-ups. In addition some of the tested mock-ups were modified to study more closely the factors that were expected to improve heat transfer from the bicycle helmets. The present paper covers making a new prototype that allowed modifications of the air channels and in- and outlet openings. In total 2 new helmet design concept mock-ups were created and tested with 13 modifications in comparison with 6 selected helmets from the previous studies including the modified versions. The mock-ups were tested at the Thermal... (More)
- The earlier studies in this measurement series defined the limits and aims for design process to create better ventilating helmets [1], and tested the insulation [2] and evaporative characteristics [3] of the designed mock-ups. In addition some of the tested mock-ups were modified to study more closely the factors that were expected to improve heat transfer from the bicycle helmets. The present paper covers making a new prototype that allowed modifications of the air channels and in- and outlet openings. In total 2 new helmet design concept mock-ups were created and tested with 13 modifications in comparison with 6 selected helmets from the previous studies including the modified versions. The mock-ups were tested at the Thermal Environment Laboratory, Lund University for insulation and evaporative resistance. Dry tests for insulation were carried on at 20 °C temperature in a wind tunnel on a thermal head manikin at the chosen air velocities of 1.6 m/s on a bald head and 1.6 m/s and 6 m/s with the wig in order to simulate the effect of hair. Wet tests were carried out with textile skin on the head manikin, using the air velocity 1.6 m/s with and without the wig. As the main result it was concluded that a well ventilating helmet is characterized by less contact with the head, and proper air channels with strategically placed air inlets and outlets. Large openings worked much better than a several small ones, yet, the care has to be taken as too large openings reduce the helmet protective capabilities. The shape and other design related modifications of the air inlets and outlets had minimal effect on ventilation. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/7866943
- author
- Aljaste, Helena ; Kuklane, Kalev LU and Heidmets, Sixten Sebastian
- organization
- publishing date
- 2015
- type
- Chapter in Book/Report/Conference proceeding
- publication status
- published
- subject
- keywords
- bicycle helmets insulation ventilation evaporative resistance design
- host publication
- International Cycling Safety Conference 2015
- editor
- Otte, Dietmar
- pages
- 8 pages
- publisher
- Medizinische Hochschule Hannover, Germany
- conference name
- 4th International Cycling Safety Conference
- conference location
- Medizinische Hochschule Hannover, Germany
- conference dates
- 2015-09-15 - 2015-09-16
- language
- English
- LU publication?
- yes
- id
- 67c67fae-7173-43f6-99ba-bf8a2eccd684 (old id 7866943)
- date added to LUP
- 2016-04-04 10:06:57
- date last changed
- 2018-11-21 20:56:50
@inproceedings{67c67fae-7173-43f6-99ba-bf8a2eccd684,
abstract = {{The earlier studies in this measurement series defined the limits and aims for design process to create better ventilating helmets [1], and tested the insulation [2] and evaporative characteristics [3] of the designed mock-ups. In addition some of the tested mock-ups were modified to study more closely the factors that were expected to improve heat transfer from the bicycle helmets. The present paper covers making a new prototype that allowed modifications of the air channels and in- and outlet openings. In total 2 new helmet design concept mock-ups were created and tested with 13 modifications in comparison with 6 selected helmets from the previous studies including the modified versions. The mock-ups were tested at the Thermal Environment Laboratory, Lund University for insulation and evaporative resistance. Dry tests for insulation were carried on at 20 °C temperature in a wind tunnel on a thermal head manikin at the chosen air velocities of 1.6 m/s on a bald head and 1.6 m/s and 6 m/s with the wig in order to simulate the effect of hair. Wet tests were carried out with textile skin on the head manikin, using the air velocity 1.6 m/s with and without the wig. As the main result it was concluded that a well ventilating helmet is characterized by less contact with the head, and proper air channels with strategically placed air inlets and outlets. Large openings worked much better than a several small ones, yet, the care has to be taken as too large openings reduce the helmet protective capabilities. The shape and other design related modifications of the air inlets and outlets had minimal effect on ventilation.}},
author = {{Aljaste, Helena and Kuklane, Kalev and Heidmets, Sixten Sebastian}},
booktitle = {{International Cycling Safety Conference 2015}},
editor = {{Otte, Dietmar}},
keywords = {{bicycle helmets insulation ventilation evaporative resistance design}},
language = {{eng}},
publisher = {{Medizinische Hochschule Hannover, Germany}},
title = {{The effects of air channel construction and design elements on heat transfer characteristics of bicycle helmets for commuters}},
url = {{https://lup.lub.lu.se/search/files/5464732/7866945.pdf}},
year = {{2015}},
}