Performance of the cage wheels with perfect chevron and staggered echelons of half-width lugs in wet clay soil | |
| Author | Siswoyo Soekarno |
| Call Number | AIT Diss. no.AE-03-03 |
| Subject(s) | Wheels Clay soils Chevrons |
| Note | A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Engineering, nt, Resources and Development |
| Publisher | Asian Institute of Technology |
| Series Statement | Dissertation ; no. AE-03-03 |
| Abstract | To improve the performance of power tillers in wet clay soils, cage wheels are commonly used. A number of recent studies provide evidences that cage wheels can improve traction and floatation of vehicles in soft soils. The information and understanding about the arrangement of lugs on the cage wheels to generate optimum performance is still inadequate. Furthermore, most studies trying to address these issue in the past were carried out under predetermined constant slip and sinkage which, thus, limits their applicability to simulate the real life situations where sinkage and slip constantly changes. Thus studies with free sinkage of the test wheels were needed. This study was designed to investigate the effect of type of lug arrangement, slip and lug spacing on the performance of cage wheels under free sinkage. The experiments were carried out in a soil bin with clay soil with 51% (dry basis) average soil moisture content and 140 kN average soil cone index. A special frame to test the cage wheels with free sinkage was mounted on a soil bin carriage. Its total weight was set to about half the weight of commonly used power tillers in Asia as only one wheel as used for testing.The lug spacing was varied to 24° and 30°, and wheel slips were varied to 10%, 15%, 25%, 35% and 50%. All tests were conducted at average 20 rpm (3.13 km/h) rotational speed of the wheel. The pull and lift forces produced by the cage wheels were measured by using an octagonal ring transducer, and torque was measured by a torque transducer. The sinkage was measured by the displacement transducer. Data obtained were amplified and recorded an a data logger. The performance of cage wheels with staggered echelons of half-width lugs and cage wheels with perfect chevron arrangement were compared with the performance of normal cage wheels. Normal cage wheel is the wheel with straight lugs (right angle) on the wheel rim. The results revealed that an increase of wheel slip increased the pull and lift forces for all cage wheels tested. Normal cage wheel gave the highest pull forces compared to other cage wheels tested i.e. 0.89 kN, 1.50 kN, 1.52 kN, 1.61 kN and 1.62 kN at 10%, 15%, 15%, 35% and 50% wheel slips, respectively. On the other hand, cage wheel with staggered echelons of half-width lugs at 24° lugs spacing gave the highest lift forces i.e. 1.03 kN, 0.95kN, 1.01 kN, 1.06 kN and 1.91 kN at 10%, 15%, 15%, 35% and 50% wheel slips, respectively. The wheel sinkage of all cage wheels increased with the increase in wheel slip. Cage wheel with perfect chevron arrangement had least sinkage among the three cage wheels tested i.e. 10.5 cm, 12.0 cm, 13.0 cm, 14.3 cm and 15.3 cm at 10%, 15%, 15%, 35% and 50% wheel slips, respectively, while cage wheel with staggered echelons of half-width lugs at 30° lug spacing sank deeper than wheel with perfect chevron arrangement i.e. 11.1 cm, 13.7 cm, 17.0 cm and 18.7 cm at 10%, 15%, 15%, 35% and 50% wheel slips, respectively. Wheel slips significantly affected the drawbar power of all cage wheels. Normal cage wheel required the biggest power viz. 0.69 kW, 1.11 Kw, 0.99 kW, 0.92 kW and 0.71 kW at 10%, 15%, 15%, 35% and 50% wheel slips, respectively. However, in terms of tractive efficiency, the cage wheel with staggered echelons of half-width lugs at 30° lug spacing achieved the highest efficiency i.e. 41.03%, 67.60%, 59.57%, 52.30% and 25.50% at 10%, 15%, 15%, 35% and 50% wheel slips, respectively. This study revealed that the wheel with perfect chevron lugs arrangement gave lesser sinkage and lower traction. Based on the results obtained in this experiment, cage wheel with staggered echelons with half-width lugs at 30° lug spacing gave the best results compared to the other cage wheels tested. It could provide higher floatation and reduced wheel sinkage. This will help efficient use of power tillers in soft paddy fields. |
| Year | 2003 |
| Corresponding Series Added Entry | Asian Institute of Technology. Dissertation ; no. AE-03-03 |
| Type | Dissertation |
| School | School of Environment, Resources, and Development (SERD) |
| Department | Department of Food, Agriculture and Natural Resources (Former title: Department of Food Agriculture, and BioResources (DFAB)) |
| Academic Program/FoS | Agricultural and Food Engineering (AE) |
| Chairperson(s) | Salokhe, Vilas M.; |
| Examination Committee(s) | Singh, Gajendra;Athapol, Noomhorm;Tong, Jin; |
| Scholarship Donor(s) | DUE Project, University of Jember, Jember, Indonesia; |
| Degree | Thesis (Ph.D.) - Asian Institute of Technology, 2003 |