#22 Solve NaN in submerged conditions

src/macrorugo/macrorugo.ts

@@ -171,7 +171,7 @@ export class MacroRugo extends Nub {
             /** Velocity at the bed §2.3.2 Cassan et al., 2016 */
             this.u0 = Math.sqrt(2 * g * S * D * this.R / (this.calcCd(this.calc_fFr(this.U0)) * C));
             /** turbulent length scale (m) within the blocks layer (alpha_t) */
-            const alpha = uniroot(this.resolveAlpha_t, this, 0, 100);
+            const alpha = uniroot(this.resolveAlpha_t, this, 1E-6, 100);
             /** averaged velocity at the top of blocks (m.s-1) */
             const uk = this.calcUz(alpha);
             /** Equation (13) Cassan et al., 2016 */