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:
In agricultural crop threshers, the function of the aspirator blower fan is to:
Options:
(A) Cool the bearings of the threshing cylinder
(B) Separate lighter chaff, husk, and dust from clean grain using terminal velocity differences
(C) Crush the straw into smaller bhusa pieces
(D) Convey the grain into the bagging elevator by positive displacement
Answer Key:
B
Step-by-Step Solution & Explanation
An aspirator creates an upward or cross-flow air current that lifts lighter particles (chaff, glumes, fine straw dust) whose terminal velocities are less than the air velocity, leaving the heavier clean grain to fall into the collection hopper.