The effect of rowing headgear on forced convective heat loss and radiant heat gain on a thermal manikin headform

Abstract

Both radiant and forced convective heat flow were measured for a prototype rowing headgear and white and black cotton caps. The measurements were performed on a thermal manikin headform at a wind speed of 4.0 m · s⁻¹ (s = 0.1) in a climate chamber at 22.0°C (s = 0.05), with and without radiant heat flow from a heat lamp, coming from either directly above (90°) or from above at an angle of 55°. The effects of hair were studied by repeating selected measurements with a wig. All headgear reduced the radiant heat gain compared with the nude headform: about 80% for the caps and 95% for the prototype rowing headgear (P < 0.01). Forced convective heat loss was reduced more by the caps (36%) than by the prototype rowing headgear (9%) (P < 0.01). The radiant heat gain contributed maximally 13% to the net heat transfer, with or without headgear, showing that forced convective heat loss is the dominant heat transfer parameter under the chosen conditions. The results of the headgear – wig combinations were qualitatively similar, with lower absolute heat transfer.

Keywords:

• Sports headgear
• rowing
• forced convective heat loss
• radiant heat gain

Acknowledgements

The authors would like to thank H. A. M. Daanen, A. Psikuta, M. Rothmaier, M. Weder, and an anonymous referee for their useful comments, and wish to express their gratitude to TNO Science and Industry for providing access to the prototype rowing headgear.