boundary-drag coefficient

例句：

1. 1. The boundary drag coefficient is a critical factor in determining the efficiency of a vehicle's engine.
   边界阻力系数是决定车辆发动机效率的关键因素。
2. 2. The study of boundary drag coefficient has significant implications for the design of aircraft wings.
   边界阻力系数的研究对于飞机机翼的设计具有重要意义。
3. 3. The boundary drag coefficient can be influenced by various factors, including air density and temperature gradients.
   边界阻力系数可以受到多种因素的影响，如空气密度和温度梯度。