03310nas|a2200265 ; 450000500170000000800410001703500150005810000260007324500880009926000520018730000440023949000270028350200580031050001330036852021520050165000360265365000250268970000320271470000430274670000410278970000420283071000480287281000590292085600650297920260817173405.0951012s1994    th  uzm rtt  00|  a1eng d  a.b101514611 aBadiger, Shrinivas M.12aA comparative study of the methods for the design of level basin irrigation systems  aBangkok :bAsian Institute of Technology,c1994  a152 leaves :bill. +e1 online resource1 aThesis ;vno. IR-93-14  aThesis (M.Eng.) - Asian Institute of Technology, 1993  aA thesis submitted m partial fulfillment of the requirement for the degree of Master of Engineering, School of Civil Engineering  aLevel basin irrigation system is one of the oldest and widely used surface irrigation methods. A review of the design procedures for level basins indicates that the analytical design methods could be broadly grouped as volume balance, zero inertia, kinematic-wave and fully dynamic. Most available hydraulic models presently used, consider unit width approach in the design which does not exactly reflect the flow process in level basins. Volume balance models used are simple, but fail to simulate the advance with a reliable accuracy. While, zero inertia models are quite complex and impractical due to the requirements of inputs, and computing facilities at field situations. Small field sizes, low inflows, single turnouts, and irregular field shapes characteristic to Asian irrigation practice limit the use of these models. Theoretically based zero inertia models and volume balance approaches were studied with reference to their applicability to wide, small level basins. Field experiments were conducted considering two basin sizes 780 sq.m and 585 sq.m, and three inflow rates 40, 30 and 20 lps. Kostiakov forms of adjusted infiltration functions performed well, compared to modified Kostiakov, SCS and Philip forms of infiltration functions when used in zero inertia models. Zero inertia models were found better in simulating the advance characteristics, while volume balance approaches performed very well in predicting time of application and percolation losses. An approach using combination of zero inertia and volume balance was suggested wherein advance characteristics derived from zero inertia (Walkers model) for a given set of inflow and soil characteristics may be directly used with volume balance approach (Gupta et al. 1983) for computing the management parameters. The hybrid approach is simple and does not necessarily require computing facilities, while the inaccuracies of volume balance methods were also overcome. An alternative procedure using the technique of dimensional analysis similar to Sharma (1978) was used to derive spread characteristics in level basins, which gave comparable results with the observed. 0aIrrigationxResearchxSri Lanka 0aIrrigationxResearch1 aMurty, V.V.N.,eChairperson1 aKono, Yasuyuki,eExamination committee1 aLoof, Rainer,eExamination Committee1 aMurali, N. S.,eExamination committee2 aThe Government of Japan,eScholarship donor2 aAsian Institute of Technology.tThesis ;vno. IR-93-14  3Full-Textuhttp://203.159.5.9/ait-thesis/detail.php?q=B15973