Capelli C, Rosa G, Butti F, Ferretti G, Veicsteinas A, di Prampero P E
Dipartimento di Scienze e Tecnologie Biomediche, Sezione di Fisiologia, Udine, Italy.
Eur J Appl Physiol Occup Physiol. 1993;67(2):144-9. doi: 10.1007/BF00376658.
Traction resistance (Rt) was determined by towing two cyclists in fully dropped posture on bicycles with an aerodynamic frame with lenticular wheels (AL), an aerodynamic frame with traditional wheels (AT), or a traditional frame with lenticular wheels (TL) in calm air on a flat wooden track at constant speed (8.6-14.6 m.s-1). Under all experimental conditions, Rt increased linearly with the square of air velocity (v2a); r2 equal to greater than 0.89. The constant k = delta Rt/delta v2a was about 15% lower for AL and AT (0.157 and 0.155 N.s2 x m-2) than for TL bicycles (0.184 N.s2 x m-2). These data show firstly, that in terms of mechanical energy savings, the role of lenticular wheels is negligible and, secondly, that for TL bicycles, the value of k was essentially equal to that found by others for bicycles with a traditional frame and traditional wheels (TT). The energy cost of cycling per unit distance (Cc, J.m-1) was also measured for AT and TT bicycles from the ratio of the O2 consumption above resting to speed, in the speed range from 4.7 to 11.1 m.s-1. The Cc also increased linearly with v2a, as described by: Cc = 30.8 + 0.558 v2a and Cc = 29.6 + 0.606 v2a for AT and TT bicycles. Thus from our study it would seem that AT bicycles are only about 5% more economical than TT at 12.5 m.s-1 the economy tending to increase slightly with the speed.(ABSTRACT TRUNCATED AT 250 WORDS)
通过在平坦的木质跑道上，在平静空气中以恒定速度（8.6 - 14.6米/秒）牵引两名处于完全俯身姿势的骑行者，来测定牵引阻力（Rt）。骑行者分别骑在带有双凸透镜形车轮的空气动力学车架自行车（AL）、带有传统车轮的空气动力学车架自行车（AT）或带有双凸透镜形车轮的传统车架自行车（TL）上。在所有实验条件下，Rt随空气流速的平方（v2a）呈线性增加；r2大于或等于0.89。与TL自行车（0.184 N·s2·m-2）相比，AL和AT自行车的常数k = ΔRt/Δv2a约低15%（分别为0.157和0.155 N·s2·m-2）。这些数据首先表明，就机械能节省而言，双凸透镜形车轮的作用可忽略不计；其次表明，对于TL自行车，k值基本上与其他带有传统车架和传统车轮的自行车（TT）所测得的值相等。还在4.7至11.1米/秒的速度范围内，通过静息时以上的耗氧量与速度之比，测量了AT和TT自行车每单位距离的骑行能量消耗（Cc，焦耳/米）。Cc也随v2a呈线性增加，AT和TT自行车的表达式分别为：Cc = 30.8 + 0.558 v2a和Cc = 29.6 + 0.606 v2a。因此，从我们的研究来看，在12.5米/秒的速度下，AT自行车似乎仅比TT自行车经济约5%，经济性随速度略有增加。（摘要截选至250字）
