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The Delft Sand, Clay & Rock Cutting Model, 2019a

The Delft Sand, Clay & Rock Cutting Model, 2019a

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<strong>Rock</strong> <strong>Cutting</strong>: Atmospheric Conditions.<br />

<br />

cos cos sin sin 0<br />

<br />

cos 2 0<br />

<br />

(8-48)<br />

Resulting in:<br />

1 <br />

<br />

2<br />

<br />

2<br />

<br />

4 2<br />

(8-49)<br />

With:<br />

1<br />

sin <br />

sin cos <br />

(8-50)<br />

2<br />

This gives for the horizontal cutting force:<br />

<br />

<br />

2sin <br />

F h w h w <br />

1<br />

sin <br />

c T i T i HT<br />

<br />

<br />

(8-51)<br />

For each side of the wedge the normal force is now (the total normal/vertical force is zero):<br />

<br />

<br />

<br />

<br />

cos <br />

F h w h w <br />

1<br />

sin <br />

n T i T i VT<br />

(8-52)<br />

Evans Brittle Horizontal Force Coefficient λ HT vs. Blade Angle α<br />

φ=00°<br />

Brittle Horizontal Force Coefficient λ HT (-)<br />

100<br />

10<br />

φ=05°<br />

φ=10°<br />

φ=15°<br />

φ=20°<br />

φ=25°<br />

φ=30°<br />

φ=35°<br />

φ=40°<br />

© S.A.M.<br />

1<br />

15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100<br />

Blade Angle α (Degrees)<br />

Figure 8-20: <strong>The</strong> brittle-tear horizontal force coefficient λHT (Evans).<br />

φ=45°<br />

Copyright © Dr.ir. S.A. Miedema TOC Page 263 of 454

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