DESIGN, CONSTRUCTION AND PERFORMANCE EVALUATION OF AN AXIAL-FLOW MILLET THRESHER

TABLE OF CONTENTS
Title Page
Abstract
Table of Contents

CHAPTER ONE
1.0       Introduction
1.1       Agriculture and World Population
1.2       Growth, Development and Adaptation of Millet
1.3       Economic Importance of Millet
1.4       Classification of Types of Millet
1.5       Problem Statement
1.6       Justification
1.7       Objectives

CHAPTER TWO
2.0       Literature Review
2.1       Species of Millet and its Areas of Production
2.2       Reviews on the Physical Properties
2.3       Trends in Development of Threshers
2.4       Developments in Millet Threshers
2.5       Demerits of Traditional Methods of Threshing
2.6       Factors Affecting the Performance of Threshers
2.7       Essential Components of Threshers
2.8       Types of Mechanical Threshers
2.9       Energy Needs for Threshing of Crops
2.10     Limitations of Existing Threshers

CHAPTER THREE
3.0       Materials and Methods
3.1.0    Determination of physical properties of grains
3.1.1    Determination of densities of millet grains
3.1.2    Determination of angle of repose of grains
3.1.3    Coefficient of friction of grains with different materials
3.2       Design Considerations
3.3       Selection Materials for the Thresher
3.4       Instrumentation and test materials
3.5       Determination of Crop Moisture Content
3.6       Determination of Cylinder Speed
3.7       Determination of Feed Rate
3.8       Concave Clearance and Sieve Size
3.9       Machine Design
3.9.1 Determination of pulley dimensions
3.9.1.1 Determination of the cylinder shaft drive pulley size
3.9.1.2 Determination of the fan shaft driven pulley size
3.9.1.3 Determination of the shaker shaft driven pulley size
3.9.2 Determination of belt lengths
3.9.2.1 Length of cross belt between prime mover and cylinder pulleys
3.9.2.2 Length of open belt between cylinder and fan pulleys
3.9.2.3 Length of open belt between cylinder and reciprocating unit‟s pulleys
3.9.3 Determination of angles of lap of belts on pulley
3.9.4 Determination of belt tensions
3.9.5 Determination of weight of fan
3.9.6 Determination of air discharge rate
3.9.7 Determination of power required in fan and shaker mechanism
3.9.8 Determination of total torque and power in thresher
3.9.9 Determination of tensions in belts
3.9.10 Determination of reactions on bearings supporting the drum
3.9.10.1 Vertical component of reactions on bearings
3.9.10.2 Horizontal component of reactions on bearings
3.9.11 Determination of bending and torsional moments
3.9.12 Determination of cylinder shaft diameter
3.9.13 Determination of diameter of reciprocating mechanism
3.9.14 Determination of diameter of fan shaft
3.10 Cost of Production of the Thresher
3.11 Working Principles and Description of the Thresher
3.12 Performance Evaluation Parameter of the Millet Thresher
3.12.1 Threshing efficiency (TE)
3.12.2 Cleaning efficiency (CE)
3.12. 3 Mechanical grain damage (MD)
3.12.4 Scatter loss (SL)
3.12.5 Throughput capacity (TC)
3.13 Design of Experiment and Analysis of Data

CHAPTER FOUR
4.0       Result and Discussion
4.1       Physical Properties of Pearl Millet
4.1.1    Result of one thousand unit mass and densities of millet grains
4.2       Effect of Feed Rate at Different Moisture Contents on Threshing Efficiency
4.3       Effect of Feed Rate at Different Moisture Contents on Cleaning Efficiency
4.4       Effect of Feed Rate at Different Moisture Contents on Scatter Loss
4.5       Effect of Feed Rate at Various Moisture Contents on Mechanical Grain Damage
4.6       Effect of Feed Rate at Various Moisture Contents on Throughput Capacity
4.7 Effect of Drum Speed at Various Moisture Content on Threshing Efficiency
4.8 Effect of Drum Speed at Various Moisture Content on Cleaning Efficiency
4.9 Effect of Drum Speed at Various Moisture Content on Mechanical Grain Damage
4.10     Effect of Drum Speed at Various Moisture Content on Scatter Loss
4.11     Effect of Drum Speed on Throughput Capacity
4.12     Effect of Threshing Efficiency on Cleaning Efficiency
4.13     Relationship between Scatter Loss and Throughput
4.14     Regression of Throughput on Grain Damage
4.15     Analysis of Variance for Threshing Efficiency of Developed thresher
4.16     Duncan‟s Multiple Range Test for Main Effects on Threshing Efficiency
4.17     Analysis of Variance for Cleaning Efficiency of Developed thresher
4.18     Duncan‟s Multiple Range Test for Main Effects on Cleaning Efficiency
4.19     Analysis of Variance for Mechanical Grain Damage of Developed thresher
4.20     Duncan‟s Multiple Range Test for Main Variables on Mechanical Grains Damage from Developed Thresher
4.21     Analysis of Variance (ANOVA) for Scatter Loss of the Developed Thresher
4.22     Duncan‟s Multiple Range Test for Main Variables on Scatter Loss from Developed Thresher
4.23     Analysis of Variance (ANOVA) for Throughput of Developed Thresher
4.24     Duncan‟s Multiple Range Test for Main Variables on Throughput of          Developed Thresher
4.25     Comparison of other Millet Threshers with the Developed Axial-Flow Thresher

CHAPTER FIVE
5.0       Summary, Conclusion and Recommendation
5.1       Summary
5.2       Conclusion
5.3       Recommendation
REFERENCES

ABSTRACT
Existing millet threshers have not been performing up to expectation. Based on this, the physical properties of pearl millet grains were determined and used to design an axial-flow millet thresher. The length, width, thickness, geometric diameter, sphericity, surface area of the grains were found to decreased with decrease in moisture content of the grains from 11.6 to 7.8 %. The bulk and true densities of the grains were gotten as 0.73 and 1.14 kg m-3 respectively and the coefficient of friction of the grains on sheet metal and aluminium were obtained as 0.35 and 0.36 respectively. The thresher was made from locally available materials and evaluated at 3 levels of crop moisture content of 7.8, 9.7 and 10.3 % (dry basis), 4 levels of manual feed rates of 60, 90, 120 and 150 kg hr-1 and 4 levels of cylinder speeds of 5.5, 7.3, 9.2 and 11.0 ms-1. The collected data were analyzed using analysis of variance and Duncan multiple range test. The thresher had 96.5 % and 95.2 % threshing and cleaning efficiencies respectively. The mechanical grain damage and scatter loss from the thresher were 2.65 % and 27.6 % respectively. The throughput capacity of 60 kg hr-1 was obtained at 9.7 % crop moisture content and 150 kg hr-1 feed rate. The analysis of variance showed that for threshing efficiency, cleaning efficiency, grain mechanical damage, scatter loss and throughput, there was no significant difference at 1 % level of confidence in the interactions of the three independent variables. But the analysis showed that the main effects of crop moisture, cylinder speed and feed rate had high significant differences on each of the performance indices evaluated. The Duncan multiple range test showed that the best crop moisture content for threshing was 7.8 %. It yielded 38kg per hour throughput, 94.8 % threshing efficiency, 94.4 % cleaning efficiency and grains damage of 2.5 %. The highest feed rate (150 kg hr-1) and the two  uppermost speeds gave best results.

CHAPTER ONE
1.0       Introduction
1.1       Agriculture and the World Population
Food is a very important component of human existence. Agriculture plays a vital role in the sustenance and continuous existence of man and his domestic animals. With the world population of seven billion and growing at the rate of 1.1 % per annum (www.worldmeters.org), there is the constant need to increase food production. The continuous increase in the world population would invariably increase the competition on food, land and other resources for agriculture (www.mapsofworld.com). For example, lands that were once used for farming are now used for either residential building or some other non-agricultural based industries. This has led to the need to increase the use of technology in order to feed the ever increasing population and to make maximum use of available resources to feed the population.

Cereals and legumes are some of the essential and most consumed food by man (www.fao.org/docrep). Cereals are widely consumed and utilized by man. They serve as raw materials for food and drug industries. This can be observed by the large metric tonnes of each of them reserved in silos and grains reserves world over (Mckee, 2011). Cereals are also used as animal feed and their stalks are as well useful to man in building temporary fence and as thatch for roofing of mud houses in villages (Mula et al., 2009). Thus the importance of cereals to man cannot be over emphasized.

Millet is a kind of cereals that is widely grown in Africa and India. Millets are extremely important in the semi arid tropics of Africa and produced in 18.50 hectares by 28 countries covering 30 % of the continent (Obilana, 2007). According to DAFF (2011)...

For more Agricultural Engineering Projects click here
================================================================
Item Type: Project Material  |  Attribute: 118 pages  |  Chapters: 1-5
Format: MS Word  |  Price: N3,000  |  Delivery: Within 30Mins.
================================================================

Share:

No comments:

Post a Comment

Select Your Department

Featured Post

Reporting and discussing your findings

This page deals with the central part of the thesis, where you present the data that forms the basis of your investigation, shaped by the...

Followers