Bioresource and Agricultural Engineering Commons^™

Ground Driven Powered Tillage, Larry G. Wells, E. M. Smith, D. E. Hammett, H. J. Thompson Jr.

Biosystems and Agricultural Engineering Faculty Publications

A ground driven powered tillage device is described which utilizes a passive rolling coulter propelled through the soil by a prime mover. The reaction torque imparted by the soil to the coulter is delivered via a torque transfer unit to a powered tillage blade. The tillage blade rotates counter to the direction of the passive rolling coulter and prepares a tilled furrow of some predetermined depth for seed placement and coverage.

Analysis is presented in which the torque developed by a passive rolling coulter engaging the soil is predicted. A relationship is presented for determining the velocity ratio between the …

Analysis And Testing Of Powered Tillage Blades, Larry G. Wells, E. M. Smith, D. E. Hammett

Biosystems and Agricultural Engineering Faculty Publications

Fundamental design considerations for powered rotary tillage blades are presented and discussed. The relationship between blade angular velocity and the geometric dimensions of cutting edges is specified for tillage blades rotating counter to the direction of travel and assuming a typical forward speed for tillage.

Analyses showed that a powered blade rotated opposite to the direction of travel can be operated at relatively lower angular velocities than can one rotated in the direction of travel to achieve equivalent blade velocity and acceleration relative to the soil. Furthermore, a blade rotated opposite to the direction of travel requires relatively lower power …

Dynamic Simulation Of Animal Growth And Reproduction, Otto J. Loewer Jr., Edward M. Smith, Gerald Benock, Nelson Gay, Thomas C. Bridges, Larry G. Wells

Biosystems and Agricultural Engineering Faculty Publications

A rather unique systems analysis approach has been made to simulate the utilization of dry matter by ruminant animals, and the natural breeding and reproduction process within a herd. Physiological factors occurring over time and the time related effects of these factors are simulated.

Wind Drag On Burley Tobacco Plants, James H. Casada, Linus R. Walton, Larry G. Wells

Biosystems and Agricultural Engineering Faculty Publications

Drag coefficient and center of resistance to wind forces were determined for four varieties of burley tobacco at three stages of growth and using wind velocities ranging from about 3 to 17 m/s. Drag coefficients determined ranged from about 0.024 at the highest velocity to about 0.081 at the lowest velocity. Stage of growth and wind velocity had significant effects on drag coefficient. Variety did not have a significant effect on drag coefficient. Mean center of resistance varied from 42.3 percent of the distance from bottom leaf to top leaf at the early stage of growth to 71.2 percent at …

The Influence Of Harvesting Strategies And Economic Constraints On The Feasibility Of Farm Grain Drying And Storage Facilities, Otto J. Loewer Jr., Thomas C. Bridges, G. M. White, Douglas G. Overhults

Biosystems and Agricultural Engineering Faculty Publications

The economic return to on-the-farm grain drying and storage facilities is influenced by many factors including harvesting strategies, facility management, market conditions, energy considerations, and facility design. This study evaluates the influence of these factors on expected net return.

Economic Comparison Of Alternative Burley Tobacco Harvesting Practices By Computer, Thomas C. Bridges, Larry G. Wells, George A. Duncan, John N. Walker

Biosystems and Agricultural Engineering Faculty Publications

The computer model CATCH (Computer Analysis of Tobacco Cutting and Housing) was developed to provide the individual tobacco producer with management information concerning alternative methods of harvesting burley tobacco. CATCH utilizes specific producer in-puts to analyze 24 alternative burley production systems and presents up to four economic rankings containing costs, equipment and labor for each system. The economic rankings aid the producer in decision making with regard to his own operation.

The Influence Of Harvest Rate And Drying Time On Grain Drying And Storage Facility Selection, Thomas C. Bridges, Otto J. Loewer Jr., Douglas G. Overhults

Biosystems and Agricultural Engineering Faculty Publications

No abstract provided.

Determination Of Strategy For Harvesting Burley Tobacco, Yasuhiko Miyake, Larry G. Wells, George A. Duncan, Jimmie Rankin

Biosystems and Agricultural Engineering Faculty Publications

The decision-making process associated with the scheduling of burley tobacco harvesting operations was formulated as a multi-stage decision process, and solved using a procedure called dynamic programming. The solution of a stochastic dynamic programming model provides a set of optimal decision rules, that is, a strategy. When certain user-specified parameters are provided, the decision model provides information concerning the optimal date to start harvesting, the optimal number of hours to harvest on each day, the optimal date to introduce hired labor, and the optimal number of workers which should be hired.

The solution of the dynamic programming model makes it …

A Computer Model For Evaluating Corn Harvesting, Handling, Drying And Storage Systems, Thomas C. Bridges, Otto J. Loewer Jr., John N. Walker, Douglas G. Overhults

Biosystems and Agricultural Engineering Faculty Publications

No abstract provided.

The Response Of Various Soil Strength Indices To Changing Water Content And Bulk Density, Larry G. Wells, O. Treesuwan

Biosystems and Agricultural Engineering Faculty Publications

Various soil strength parameters were measured in the laboratory using a bevameter and a recording soil cone penetrometer. Measurements were made at various levels of soil bulk density and water content. Results were discussed in terms of similar published analyses. Two dissimilar methods of predicting vehicular tractive performance were compared and evaluated in terms of potential utility with respect to prediction of soil trafficability.

Predicted And Measured Drainable Porosities For Field Soils, R. W. Skaggs, Larry G. Wells, S. R. Ghate

Biosystems and Agricultural Engineering Faculty Publications

Experiments were conducted on large field cores to determine the relationship between drainage volume and water table depth for five soils. The measured drainage volumes were less than predicted from the soil water characteristics for three soils, but were in good agreement for the other two. Drainable porosities were calculated from both theoretical and experimental drainage volume-water table depth relationships by assuming that the unsaturated zone is essentially 'drained to equilibrium, with the water table. The experimental drainable porosities thus obtained were less than predicted.

Drainable porosities for drainage in two-dimensions were calculated from experimental results for one-dimension by assuming …

Vertical Drainage In Field Cores, Larry G. Wells, R. W. Skaggs

Biosystems and Agricultural Engineering Faculty Publications

No abstract provided.

Modeling Soil Water Movement Into Plant Roots, D. C. Slack, C. T. Haan, Larry G. Wells

Biosystems and Agricultural Engineering Faculty Publications

Mathematical model was developed which describes uptake of water by plant roots as a function of leaf and soil water potentials. The model was used to estimate transpiration from corn grown in a controlled environment under soil drying conditions. The model predicted daily transpiration quite well for the period modeled.

Computer Layout And Design Of Grain Storage Facilities, Otto J. Loewer Jr., Thomas C. Bridges, Douglas G. Overhults

Biosystems and Agricultural Engineering Faculty Publications

No abstract provided.

Facility Costs Of Centralized Grain Storage Systems Utilizing Computer Design, Otto J. Loewer Jr., Thomas C. Bridges, Douglas G. Overhults

Biosystems and Agricultural Engineering Faculty Publications

The item considered most often when estimating the cost of a grain storage facility is capacity. Of equal or greater importance is daily harvest rate. Other important considerations include drying method, materials handling equipment, energy cost, facility arrangement, labor requirements, grain quality and management ability. Only through a comparison of facilities which offer similar capacity, capability and convenience can the purchaser obtain his best system.

Large Bale Transporter For Small Tractors, Larry G. Wells

Biosystems and Agricultural Engineering Faculty Publications

No abstract provided.

Upward Water Movement In Field Cores, Larry G. Wells, R. W. Skaggs

Biosystems and Agricultural Engineering Faculty Publications

No abstract provided.

Effect Of Heated Air Drying On Soybean Oil Quality, Douglas G. Overhults, G. M. White, H. E. Hamilton, I. J. Ross, J. D. Fox

Biosystems and Agricultural Engineering Faculty Publications

No abstract provided.

Drying Soybeans With Heated Air, Douglas G. Overhults, G. M. White, H. E. Hamilton, I. J. Ross

Biosystems and Agricultural Engineering Faculty Publications

No abstract provided.