**10. Verification & validation**

One can compare the Cp obtained with that predicted by the one-dimensional momentum theory. The induction factor for a Cp (maximum) of **0.421** is **0.121869**

$$C\_p = 4a(1 - a)^2 = 0.3759\tag{27}$$

Substituting the induction factor below,

$$C\_t = 4a(1 - a) = 0.428068 \tag{28}$$

The actual torque coefficient was calculated assuming the net blade length of 35 m to account for tip/hub losses. The computed value below is indeed very close, verifying our solution.

$$C\_t = \frac{T\_{out}}{0.5 \rho u^2 A} = \frac{165373}{339261.3} = 0.487450234\tag{29}$$



*a 1/3rd of total torque generated as the simulation was performed for a single blade.*

#### **Table 3.**

*Pitch, TSR vs Torque (in N-m), Net Power (in W), and Cp.*

Now, let us finally compare our solution with QBlade and XFoils. Below is the Cp vs TSR Curve (**Figure 15**). We can see some deviation from the QBlade data and CFD. This deviation is probably due to extra turbulence caused by the rotor hub, which was accounted for in CFD but was left empty in QBlade. The energy dissipation and turbulence cause a lower figure to appear in CFD.
