Grain Cleaning, Winnowing & Specialized Harvesters: Air-Screen Cleaners, Walker Losses, Corn Snappers & Cotton Pickers

• Agricultural Storage and Thermal Processing:
• Janssen's Theory $\to$ (IV) Storage Structure: Foundational theory for calculating lateral and vertical pressure loads in deep grain silos/bins.
• CAP (Cover and Plinth) $\to$ (II) Bag Storage: Outdoor grain storage method in India where bagged grain stacks are placed on raised plinths and covered with polythene tarpaulins.
• Newton's Law of Cooling $\to$ (I) Convection: States that heat loss rate from a solid body is proportional to temperature difference with the surrounding fluid.
• Sensible Heating $\to$ (III) Constant Humidity: Heating air across psychrometric lines at constant absolute/specific humidity without adding or removing moisture.
• Matching Result: (A) - (IV), (B) - (II), (C) - (I), (D) - (III) (Option 4).

Correct option: (4) (A) - (IV), (B) - (I), (C) - (), (D) - (ttl)

• Operational Characteristics of Screw Conveyors:
• screw conveyor consists of a helical auger revolving inside a stationary U-shaped or cylindrical trough.
• Due to continuous rubbing friction between the material, auger flights, and trough wall:
• Power consumption is relatively high compared to belt conveyors or bucket elevators ($2-3$ times higher power).
• Continuous abrasive contact makes screw flights and bearings more susceptible to wear.
• Conclusion: Require relatively high power and are more susceptible to wear (Option 2).

Correct option: (2) Require relatively high power and are more susceptible to wear

• Factors Governing Air-Screen Grain Cleaner Capacity:
• An air-screen grain cleaner separates impurities based on aerodynamic drag (aspirator air duct) and particle dimensions (screens):
• Grain bed depth: Governs screen stratification and air passage.
• Size of screen surface: Width and length define total active screening area ($m^2$).
• Feeding mechanism: Ensures uniform, non-pulsing curtain flow across the full screen width.
• Percentage opening area of screen: Dictates open perforation fraction through which clean grain passes.
• Conclusion: Capacity depends on (A), (B), (C) and (D) (Option 3).

Correct option: (3) (A), (B), (C) and (D).

Arranging the sequence correctly for Physico-mechanical properties of grass and cereal stalks:

The correct chronological order is Option 4: (B), (A), (D), (C), (E)..

Correct option: (4) (B), (A), (D), (C), (E).