2021 course offerings:
- March 9 – April 14
Course Description: This course focuses on the design and operation of aeration systems for dry grain storage structures with flat, hopper and V-bottoms in corrugated steel bins, concrete silos, large diameter tanks, horizontal storage structures and outdoor piles/bunkers. The relationship between air and grain properties will be reviewed and the selection and sizing of fans and their operational management for conditioning and cooling grains will be thoroughly discussed. Ideally, students should take GEAPS 520: Quality Grain Management before taking this course, but it is not a requirement.
Course Goals: The goal of the course is to teach students the basic principles of designing and operating grain aeration systems to successfully maintain grain quality during storage. Students will understand the overall purpose of grain aeration and aeration system components as well as how to calculate and develop strategies for aeration system design and fan operational management. By the end of each lecture students will be able to answer study questions and by the end of the course students will be able to complete a case study on selecting and operating aeration control equipment.
Target Audience: GEAPS 521 is designed for people with responsibilities relating to preservation of grain quality, as well as aeration-equipment operation, design, selection and purchasing. It is intended for facility and systems designers, aeration systems vendors, facility owners and operators, elevator superintendents, location or regional managers, and anyone with a professional need to learn more about aeration system design and efficient fan operation management.
Instructors:
Dr. Dirk Maier, Professor, Iowa State University | Show Bio
Dr. Kenneth Hellevang, Professor, North Dakota State University | Show Bio
Dr. Ron Noyes, Retired Professor, Oklahoma State University | Show Bio
Dr. Ricardo Bartosik, Researcher and Extension Engineer, National Institute of Agricultural Technologies | Show Bio
The Course of Study
Week 1
Lecture 1 – Objectives of Aeration and Aeration System Components
The aim of this lecture is to show students the importance of aeration for the purpose of cooling and conditioning stored grains and to review key system components, including fans, transitions, ducts, floors, vents and controls. This lecture will include the following topics: cooling of grain to maintain grain quality and suppress insects, mites and molds; fan types; ideal air velocities; supply and transition ducts, manifolds and elbows; calculating airflow volume through ducts; roof vents; perforated flooring and fan controllers.
Lecturer: Dr. Dirk Maier
Lecture 2 – Relationship Between Air and Grain Properties
This lecture reviews the relationship between air properties (psychrometrics) and grain properties (equilibrium moisture content). It will cover the following topics: basic air properties and psychrometric relationships, grain equilibrium moisture content relationships, determining safe storage moisture contents and using psychrometrics to analyze local and historic weather data.
Lecturer: Dr. Dirk Maier; Contributor, Dr. Ricardo Bartosik
Week 2
Lecture 3 – Airflow Rates, Resistance to Airflow and Air Distribution Patterns
This lecture focuses on the relationship between airflow rates and resistance to airflow that occurs with different grain types and depths, and reviews distribution of airflow through peaked, leveled, cored and inverted grain held in storage-structure configurations with flat, hopper and V-bottoms. The lecture will also include the following topics: airflow rates required for cooling and conditioning, airflow cycle time, principles of Shedd’s Equation, the concept of frictional resistance, estimating static pressure drop through grain, estimating pressure drop through aeration system components, pressure patterns, fine material concentration and non-uniform airflow in grain.
Lecturer: Dr. Dirk Maier; Contributor: Dr. Ricardo Bartosik
Lecture 4 – Fan Sizing and Selection
This lecture will discuss the importance of proper fan sizing and selection to achieve desired operational effects. It will have two main topics for discussion: the principles of fan sizing and selection and fan performance characteristics. The lecture will also touch on fan types, sizing, and selection; direction of airflow; fan performance characteristics; and the FANS program. It will utilize the FANS program from the Post-Harvest Handling of Crops website from the University of Minnesota to better understand the FANS program.
Lecturer: Dr. Dirk Maier
Week 3
Lecture 5 – Design of Bin/Silo Aeration
This lecture will familiarize students with the engineering calculations and design considerations involved in sizing and implementing the simplest aeration systems. It will discuss aeration floor layouts and system designs for flat and hopper bottom round bins, silos, and tanks; inlet and exhaust roof venting; vent types and characteristics; and vent positioning and supporting.
Lecturer: Dr. Ron Noyes
Lecture 6 – Selecting Ambient Air for the Operation of Aeration Systems
In this lecture students will become familiar with the relationship between ambient air and aeration systems, including the importance of weather analysis. The lecture will cover equilibrium moisture content, fan control strategies, how to evaluate local and historic weather conditions and the effect of weather patterns on aeration effectiveness.
Lecturer: Dr. Dirk Maier
Week 4
Lecture 7 – Design and Layout of Aeration Systems: Flat Storage Aeration
This lecture will cover horizontal (flat) storage aeration design criteria, duct length limitations and number of ducts needed. It will also provide examples of each layout and design component of the horizontal storage system.
Lecturer: Dr. Kenneth Hellevang
Lecture 8 – Strategies for Fan Operation to Condition and Aerate Grain
This lecture will go over the considerations involved in operating aeration systems under various climatic conditions. It will review the different operational strategies used to cool and condition grain. It will contain the following topics: operational settings for aeration control systems, aeration cooling to prevent mold development and self-heating, aeration cooling to prevent insect infestation and development, aeration to condition moisture content of stored grain, aeration in upright versus horizontal structures, aeration of outdoor piles and bunkers and warming of winter-cooled grain.
Lecturer: Dr. Dirk Maier
Week 5
Lecture 9 – Design and Layout of Aeration Systems in Outdoor Piles and Bunkers
In this lecture students will be familiarized with the engineering calculations and design considerations involved in sizing and laying out the most complex aeration systems. The main topics include: storage types and design criteria, duct length limitations, duct airflow uniformity and placement, grain pile management and bunker design examples.
Lecturer: Dr. Kenneth Hellevang
Lecture 10 – Selecting and Utilizing Aeration Control Equipment
This lecture is designed to acquaint students with the advantages and disadvantages of various aeration controllers. It will cover several topics including: control system components, simple mechanical controllers, complex electromechanical controllers, microprocessor and computer-based controllers, selecting aeration controllers and predicting aeration system performance. It will include a case study on India.
Lecturers: Dr. Dirk Maier, Dr. Ron Noyes
