Subtopic: Functional requirements, principles of working, construction and operation of manual, animal, tractor and renewable energy operated equipment for tillage, sowing, planting, fertilizer application, inter-cultivation, spraying, mowing, chaff cutting, harvesting and threshing
Question Statement:
Which of the following factors DIRECTLY influence the droplet size spectrum (Volume Median Diameter, VMD) produced by a hydraulic pressure spray nozzle?
Options:
(A) Operating liquid pressure at the nozzle orifice
(B) Orifice diameter and nozzle tip design
(C) Surface tension and viscosity of the spray liquid
(D) Tractor forward gear ratio
Answer Key:
A, B, C
Step-by-Step Solution & Explanation
Droplet atomization in hydraulic nozzles is governed by liquid properties and orifice flow physics:
- Increasing spray pressure decreases droplet size (finer spray).
- Orifice size and internal core/geometry determine sheet thickness and breakup.
- Viscosity and surface tension affect Rayleigh-Taylor and Kelvin-Helmholtz atomization kinetics.
- Forward gear ratio affects field speed and ground application rate (L/ha), but NOT the atomization droplet size exiting the nozzle tip.