A rotavator has 6 flanges with 4 blades per flange, making a total of 24 blades. It operates at a rotor speed of $210\text{ rpm}$. If the forward travel speed is $3.6\text{ km/h}$ ($1.0\text{ m/s}$), calculate the length of bite (tilled soil slice length $L_b = \frac{v_f}{n \cdot Z}$) in $\text{cm}$, where $Z$ is the number of blades per flange.
Answer Key:
7.14
Step-by-Step Solution & Explanation
Rotor speed in revolutions per second:
$n = \frac{210}{60} = 3.5\text{ rev/s}$
Blades cutting in the same plane per flange $Z = 4$ (or 2 if alternating left/right; here $Z=4$ per flange plane):
Number of cuts per second per flange $= n \times Z = 3.5 \times 4 = 14\text{ cuts/s}$.
Bite length:
$L_b = \frac{v_f}{n \times Z} = \frac{1.0\text{ m/s}}{14\text{ cuts/s}} = 0.07143\text{ m} = 7.14\text{ cm}$