Question

Operating pressure for sprinkler head is considered as most practical ranging from

• A. 1.4 - 4.2 kg/cm$^2$
• B. 0.35 - 1.0 kg/cm$^2$
• C. 3.5 - 7.0 kg/cm$^2$
• D. 5.6 - 8.4 kg/cm$^2$

Hint:

To convert operating pressure:
\[ 1\text{ kg/cm}^2 \approx 10\text{ m of water head} \approx 14.22\text{ psi} \] A practical range of \( 1.4\text{ to }4.2\text{ kg/cm}^2 \) is equivalent to \( 20\text{ to }60\text{ psi} \).

Answer 1

The Correct Option is A

Step 1: Understanding the Concept:
Sprinkler irrigation systems apply water to crops by spraying it through nozzles to mimic natural rainfall.
For a sprinkler system to operate efficiently, it must maintain a specific pressure range at the nozzle head.
This operating pressure ensures proper droplet size distribution and uniform water application across the field.
Detailed Explanation:
Let us evaluate the practical pressure ranges for standard agricultural sprinkler systems:
- If the operating pressure is too low (e.g., \( < 1.0\text{ kg/cm}^2 \)), the water jet will not break up properly, producing large droplets that can damage crops and soil structure while reducing the spray radius and application uniformity.
- If the pressure is too high (e.g., \( > 5.0\text{ kg/cm}^2 \)), the water is atomized into a fine mist that is highly susceptible to wind drift and evaporation losses, requiring higher pumping energy costs.
- For standard, medium-pressure rotating head agricultural sprinklers, the most practical and efficient operating pressure range at the nozzle is \( 1.4\text{ to }4.2\text{ kg/cm}^2 \) (approximately \( 20\text{ to }60\text{ psi} \)). This range balances droplet size, spray radius, and energy consumption.

Step 2: Final Answer:
The most practical operating pressure range for a sprinkler head is \( 1.4\text{ to }4.2\text{ kg/cm}^2 \).