The Measurement, Modeling and Improvement of Product Flow Evenness off of Meter Rollers
Date
2016-07-26
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
ORCID
0000-0001-9768-6050
Type
Thesis
Degree Level
Masters
Abstract
In agricultural seeding operations the metering system, typically containing a meter roller, is the heart of the operation as it dispenses product into an airstream where it is distributed across a seeding implement and placed in the soil. Accurate and even metering of product into the airstream translates into better distribution and increased benefits for the farmer. Development of a test method and design tool (empirical model) for meter roller optimization is the main goal of this study.
A test method, called the continuous test method, to measure the metering performance was developed using an imaging apparatus to capture data of the product flow coming off of a meter roller by a measure called the product flow coefficient of variation (CV). The lower the product flow CV is the more even the product flow is. There are three main settings to note; first, defining a frame-per-flute (fPFL) ratio of 10 or more must be used to ensure the camera is capturing at or above a minimum rate. Second, a constant frame height captured by the camera must be maintained throughout all testing. Third, there was minimal to no effect due to oversampling of particles and occlusion from product overlap in the range of meter speeds used (<65 RPM).
Parameterization of a meter roller in such a way that the overall design parameters can be controlled and utilized in a model for optimization is required. Two minor parameters and four major parameters define a meter roller. With these parameters, a test set of meter rollers was designed and prototyped to be tested using the continuous test method.
Analysis of the data showed that pitch ratio (PR), the number of flutes (F), and meter roller speed (ωm) were the most significant explanatory variables for predicting product flow CV. Applying a stepwise regression technique in Matlab and a polynomial expansion of the variables, the general model form was determined. Training and testing of the raw data yielded a model fit with a RMSE of 1.94. This model predicted a meter roller with 6 flutes, a PR of 1.25, and a speed of 53 RPM to yield a predicted CV of 4.30.
Description
Keywords
Meter Roller, Metering, product flow, test method, seeding, metering performance.
Citation
Degree
Master of Science (M.Sc.)
Department
Agricultural and Bioresource Engineering
Program
Agricultural and Bioresource Engineering