The image above represents turbine stiffness.

To compute for turbine stiffness, three essential parameters are needed and these parameters are **Modulus of Elasticity for Tubing (E), Moment of Inertia of Tubing (I) **and **Mean Radius of Tubing (r).**

The formula for calculating turbine stiffness:

σ = ^{EI} / _{r³}

Where:

σ = Turbine Stiffness

E = Modulus of Elasticity for Tubing

I = Moment of Inertia of Tubing

r = Mean Radius of Tubing

Let’s solve an example;

Find the turbine stiffness when the modulus of elasticity for tubing is 12, the moment of inertia of tubing is 10 and the mean radius of tubing is 4.

This implies that;

E = Modulus of Elasticity for Tubing = 12

I = Moment of Inertia of Tubing = 10

r = Mean Radius of Tubing = 4

σ = ^{EI} / _{r³}

σ = ^{(12)(10)} / _{(4)³}

σ = ^{120} / _{64}

σ = 1.875

Therefore, the **turbine stiffness **is **1.875.**

**Calculating for the Modulus of Elasticity for Tubing when the Turbine Stiffness, the Moment of Inertia of Tubing and the Mean Radius of Tubing is Given.**

E = ^{σ x r³} / _{I}

Where;

E = Modulus of Elasticity for Tubing

σ = Turbine Stiffness

I = Moment of Inertia of Tubing

r = Mean Radius of Tubing

Let’s solve an example;

Find the modulus of elasticity for tubing when the turbine stiffness is 20, the moment of inertia of tubing is 10 and the mean radius of tubing is 2.

This implies that;

σ = Turbine Stiffness = 20

I = Moment of Inertia of Tubing = 10

r = Mean Radius of Tubing = 2

E = ^{σ x r³} / _{I}

E = ^{20 x 2³} / _{10}

E = ^{20 x 8} / _{10}

E = ^{160} / _{10}

E = 16

Therefore, the **modulus of elasticity for tubing **is **16.**

Continue reading How to Calculate and Solve for Turbine Stiffness | Irrigation Water Requirement