How to model Fertilizer Spreader with the Discrete Element Method (DEM)
Altair EmployeeA fertilizer spreader is a piece of agricultural equipment designed to evenly distribute fertilizer or other materials onto a field. The spreader typically consists of a hopper for holding the material, a spreading mechanism, and wheels or an attachment to be pulled by a tractor or other vehicle.
EDEM Simulation Files used in this example can be downloaded here:
One of the primary issues with fertilizer spreaders is the potential for uneven distribution of the material. Uneven distribution can lead to some parts of the field being over-fertilized, while others being under-fertilized. This can have negative effects on crop growth, yield, and quality, and can also lead to environmental problems, such as pollution of waterways due to excess fertilizer runoff.
Other issues with fertilizer spreaders can include problems with the spreading mechanism, such as clogs or damage to the distribution system, as well as issues related to calibration, such as incorrect settings or incorrect application rates.
Altair® EDEMTM helps understand these issues early on, during the designing phase, and lead to a better design development process.
Attached you can find a fertilizer spreader model setup in EDEM. The key steps to setup a fertilizer spreader simulation are:
Step 1 - Define particle shape
Appropriate particle shape must be chosen that is representative of the physical particle shape.
Step 2 - Material Calibration
Materials should be calibrated or use existing material models:
Step 3 - Import equipment from CAD
EDEM supports many file types such as STL, STEP, IGES. Geometries are imported to EDEM via the Creator > Geometries > Import Geometry section. You can choose either the default mesh which is optimised to capture the geometry shape while minimising the mesh elements, or choose a manual mesh size. You may want to manually select the mesh if your analysis includes any forces on the equipment itself, as these forces are calculated per triangular mesh element.
Step 4 - Introduce material
Create a factory (a geometry from which materials are introduced into the system) on a virtual plane and place it above the hopper. You can then introduce material from the plane into the hopper.
Step 5 - Assign Kinematics
You can assign different types of motion to the geometries as shown here. The blades have a Linear Rotational Kinematic applied which rotates the blade geometry around the specified axis.
More complex motions such as sinusoidal or force control is also available.
These steps are outlined in our EDEM Tutorials:
For a more advanced model, you can also couple it with a CFD solver like AcuSolve to understand the effects of air on the distribution pattern.
Altair EDEM provides analysis allowing designers to:
- Understand the effects of air on the distribution pattern
- Predict bulk material behavior identifying the distribution patterns, and analysing the variation with design changes
- Virtually test designs for a wide range of materials with different properties (different kinds of seeds/fertilizers)
- Get key insight into the full design space and operating conditions like the blade speed
- Reduce the need for physical prototypes
- Design for increased reliability and equipment uptime
- Accelerate the design process