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ThesisItem Open Access Evaluation of low-cost lining materials for field channels(Department of Land and Water Resources and Conservation Engineering, Kelappaji College of Agricultural Engineering and Technology, Tavanur, 2000) Abdu, Mudesir Issa; KAU; Reema, K PSeepage losses from field channels are too high, making surface irrigation the inefficient method of water application. The high cost of lining hindered the use of most of the common lining materials for lining field channels. With an objective of identifying and testing low cost lining materials for field channels, a study was conducted at K.C.A.E.T., Tavanur. Four low-cost materials were tested in the experiments. The physical property tests on different RHA-cement types showed that the waterpercentages required to attain standard consistency of the RHA-cements ranged between 58.33 to 58.53. The mean initial setting times observed were ranging from 55.67 min, for RHA-20, to 241.39 min., for RHA-40. The final setting times ranged between 397.74 and 600.36 min. The compressive strengths of the RHA-cement made mortars were determined after 3, 7, 14, and 28 days of curing. The two factor analyses of variance revealed that both the days of curing and RHA-cement types were sources of variation. RHA-20 mortars were significantly weaker than RHA-25 and RHA-30 mortars for 7 days of curing, and for 14 and 28 days of curing a significant difference in the compressive strengths ofRHA-20 and RHA-30 was observed. The average seepage rates were obtained as 3.536, 92.786, 356.278, 26.190 and 633.296 Vm2/day for plastic, RHA-30, Kaolinitic clay, Bentonite lined and the unlined channels respectively. The respective steady seepage rates from plastic, RHA-30, Kaolinitic clay, Bentonite lined and the unlined channels were 0.984, 72.283, 260.256, 12.530 and 433.886 Vm2/day. Plastic lining saved 99.774 per cent of the seepage as compared le. ti:,unlined. RHA-20, RHA.:.25, and RHA-40 linings respectively were having steady seepage rates of 150.917,11.959, 101.161 lIm2/day and saved 65.377, 74.315, and 76.792 of the seepage against the control.The RHA-30 lined surface was the smoothest with a roughness coefficient of 0.01853, the same were 0.0236, 0.0255, 0.02497 and 0.0238 respectively for plastic, Kaolinitic clay, Bentonite and unlined surfaces. The total number of weeds grown on plastic, RHA-30, Kaolinitic clay, Bentonite and unlined surfaces respectively were 294, 7, 287, 163,and 547. The initial costs of constructing I Km length of field channel were obtained as Rs.54657.86, 83008.84, 68062.50, 81490.31 and 21000.00 for plastic, RHA-30, Kaolinitic clay, Bentonite and unlined channels respectively. The actual cost required to construct the five 10 m channels with plastic, RHA-30, Kaolinitic clay, Bentonite linings and with out lining respectively were Rs. 548.40, 832.15, 618.45, 1330.08 and 210.00. From the overall compansons of water tightness" surface roughness, weed controlling ability, structural stability, durability and cost RHA-30 lining was found to be the best among the tested lining materials. A combination type lining using plastic and RHA-cement as a cover will probably be an ideal lining, as each can complement the shortcomings of the other.ThesisItem Open Access Optimal water use and cropping pattern for Thrithala regulator-cum-bridge project(Department of Land and Water Resources and Conservation Engineering, Kelappaji College of Agricultural Engineering and Technology, Tavanur, 2001) Saritha, E K; KAU; Sathian, K KReservoir projects involve huge financial investment and hence, every drop of water stored in the reservoir must be utilised very judiciously. Allocation of water in the case of multi-purpose projects among various competing needs such as drinking water, irrigation, pisciculture, downstream flow, etc. is a matter of great concern. Hence, formulation of optimal operational policies for reservoirs has become highly essential to improve their financial viability, social acceptability and overall performance. So a study has been undertaken for a regulator-cum-bridge under construction at Thrithala in Palakkad district of Kerala state in Indian peninsular with the specific objectives of determining the optimum water allocation of the reservoir for meeting various demands on it and obtaining the optimum cropping pattern for the command area. A linear programming model was formulated to optimize the reservoir operation of the multipurpose project with the objectives of Drinking water demand, Irrigation demand, Pisciculture demand, and Downstream flow demand, in the order of priority. The deviations of the allocations from the targets to be achieved were minimized by introducing penalty coefficients to each deviation according to their order of priority. Using the irrigation allocation from this model, another Linear Programming model was formulated to obtain the optimal cropping pattern for the command area. Both models were solved using Excel Solver software package. The optimal operational plan and the optimal cropping. pattern obtained were compared with the operating plan and cropping pattern proposed by the irrigation department. The optimal operation plan with the incorporation of additional objectives was found to be more socially acceptable and economically viable. The optimal cropping pattern showed that there is more than 100% increase both in the net benefit as well as in the net area irrigated.ThesisItem Open Access Optimal number and discharge rate of emitters for coconut palm in sandy loam soil(Department of Irrigation and Drainage Engineering, Kelappaji College of Agricultural Engineering and Technology, Tavanur, 2000) Priya Nair, G; KAU; Suseela, PAgricullurClI productivity is based on the availability of required water at proper time. As water is becoming Cl limited resource its efficient utilization is very essential. The distribution of rainfall in Kcrala is not adequate to meet the total welter requirement of coconut. Coconut in Kerala are mostly grown in sandy soils which has a poor water holding capacity. So drip irrigation is the best method of irriqation for coconut in this soil. The efficient design of drip irrigation system involves the optimal spacing of emitters, correct discharge rate anr' duration of inigc\lion based on the movement of soil moisture front. So the study of moisture distribution pattern under chip irriU(ltion is helpful in deciding optimum number and discharge rate of emitters and duration of irriqation required for coconut palms The study was conducted in the river side coconut gc)rdr.n of the instruclional Farm, I~CAET, TaVilrH1I. The size of the plot was 28x63m. The soil properties viz texture. bulk dcn-itv. infiltration rate, field capacity. hydraulic conductivity and permanent \vi!;JI1q point were observed. The drip system was installed in the fielc! Two different c!ischarge rates (4 and 8lph) and three f combination of number of emitters (3,<'1 & 6) were selected for the study. The maximum vertical and horizontal advance of soil moisture front for both the discharge rates (4 and 8 Iph) were noted. Empirical equations were also developed for both vertical and horizontal advance. The soil moisture contents were determined at different horizontal anc! vertical distances from the emitter, before irriqation, 1 hour, 24 hours and 3 days after irrigation by gravimetric method. The soil moisture contour maps were plotted and the moisture distribution efficiency was calculated for each treatment at all depths. The maximum vertical and horizontal advance was observed for 8 lph emitter compared to 4 Iph emitter. The welting front from a single emitter produced C\ bulb like \Netting pattern for both the discharges. The size of the wetting bulb increased with increase in discharge rate. The study revealed that 4 numbers of 8 Iph emitters give more uniform distribution compared to all the other treatments.ThesisItem Open Access Optimization of greenhouse ventilation for humid tropics(Department of Irrigation and Drainage Engineering, Kelappaji College of Agricultural Engineering and Technology, Tavanur, 2000) Jinu, A; KAU; Abdul Hakkim, V MIn any agricultural sector, the need of the hour is to maximize the yield per unit area to cater the needs of our population, which is exploding at an alarming rate. Protected cultivation or controlled environment agriculture is one of the methods to increase the crop production from unit area. Of the various forms of protected cultivation, greenhouses are most common. Our state falls under humid tropical climatic condition. Greenhouse cooling is to be done during peak hours of daytime under this climatic condition. Ventilation plays an important role in green house cooling. A study was conducted to determine the optimum greenhouse ventilation for humid tropics and to analyze the effect of different cooling methods viz. natural ventilation, fan and pad system, mist system and roof shading on greenhouse cooling. The study showed that natural ventilation could reduce the greenhouse temperature to a great extent. The different percentages of ventilation used for the experiment were 13.8, 11.5, 9.2, 6.9, 4.6 and 2.3. The study was also conducted without ventilation. As percentage ventilation increases, greenhouse cooling increases and inside relative humidity decreases. 13.8 percent ventilation gave maximum greenhouse cooling and this value is taken as the optimum percentage of natural ventilation. But the natural ventilation alone cannot meet the cooling requirement during peak hours. Fan and pad system is found to be not effective for greenhouse cooling in this particular study. Even 2.3 percentage of natural ventilation condition gave better cooling than fan and pad cooling system. Misting is an effective method to lower down the greenhouse temperature within a short period of time. Misting was done along with fans at different percentages of ventilation and the different climatic parameters were studied. The results showed that while misting, the maximum cooling was obtained at 2.3 percent of ventilation. Effect of roof shading on greenhouse cooling was tested with one shade net over the greenhouse. Roof shade has a significant effect on greenhouse cooling. Th inside temperature of the greenhouse was higher than the outside temperature by more than lOoe during peak hours of the day time, when no ventilation was provided and fan and pad system, mist system and shade cover were not used. But when the green house was covered with a shade net, an inside to outside temperature difference of one or two degree was observed. Also, while operating fan and pad system and mist system, shaded condition gave better cooling. Fan and pad system operated without shade cover, could not bring down the greenhouse temperature below ambient temperature. But for the shaded condition, greenhouse temperature could be lowered to a value less than the ambient temperature. Misting under shaded condition at 2.3 percent ventilation gave maximum cooling. Misting inside an unshaded greenhouse at 2.3 percent ventilation could bring down the greenhouse temperature to 32°C, but misting inside a shaded greenhouse at 2.3 percent ventilation lowered the greenhouse temperature to 29°C. Use of two shade net layers did not give any additional cooling, and at this condition the light intensity inside the greenhouse was only 10 percent of the outside light intensity. It only increases the cost of the greenhouse and hence it is not recommended to use two shade net layers for greenhouses.ThesisItem Open Access Simulation of a Reservoir system with multiple objectives(Department of Irrigation and Drainage Engineering, Kelappaji College of Agricultural Engineering and Technology, Tavanur, 2000) Leena, Divakar; KAU; Mary Regina, FDuring the past three decades, the application of the systems approach to reservoir management application has been established as one of the most important advances made in the field of water resources engineering. Water resources planning has become exceedingly complex and is bound to become even more complex in the future considering the various demands. Application of sophisticated techniques for scientific planning and utilisation of the limited available water resources has become highly necessary to meet the growing demands of various types of consumptive and non-consumptive needs. Though India has been endowed with plenty of rainfall, the distribution is uneven both in time and space. A reservoir system simulation model reproduces the hydrologic and in some cases economic performance of a reservoir system for given inflow and operating rules. A computer simulation model for a multipurpose reservoir system was developed and tested for Peechi reservoir of Kerala state in south India. The model was designed for monthly operation with historic inflow of 35 years. The model obtains the monthly releases for various uses. The monthly water requirements for different purposes like drinking, irrigation, pisciculture and recreation are taken as the target to be achieved by the model. Out of the different uses only irrigation demand had monthly variation and the rest were taken as constants along with the dead storage and the maximum capacity for opening of the shutters. The objective of the model is to minimise the deviations of the release from the targets for each demand. The model has been formulated with appropriate priorities, which satisfy the continuity and physical conditions of the system. The priorities of different water demands can be altered at any stage of the operation according to the changing needs of the region The program is written in Visual Basic-6.0 and the results gave the monthly releases and deficits of different demands. One advantage of the model is that even non technical decision makers can comprehend the results obtained from this. The efficiency of the model is such that the solution can be obtained in the quickest time possible and is very user friendly.ThesisItem Open Access Optimal cropping pattern for the better utilization of minor irrigation schemes(Department of Irrigation and Drainage Engineering, Kelappaji College of Agricultural Engineering and Technology, Tavanur, 2000) Bindu, J; KAU; Joby V, PaulA monthly irrigation planning model was formulated for determining the optimal cropping pattern in an existing lift irrigation scheme. The study deals with the use of Linear Programming technique which is a powerful tool in systems analysis for obtaining an optimal cropping pattern from various alternatives for a command area by the conjunctive use of surface water. The optimal cropping pattern was selected for two purposes, i e. to maximise the net economic benefit from the command area for an year and to maximise the net area put under cultivation in an year. Appropriate constraints were also included while formulating the model on total cropping area of each month, cropping area of each crop, surface water availability and monthly crop water requirement etc. The model is found very flexible to alter the constraints . makers decisions from time to time based on socio-economic considerations.ThesisItem Open Access Performance evaluation of hydrocyclone filter(Department of Irrigation and Drainage Engineering, Kelappaji College of Agricultural Engineering and Technology, Tavanur, 2001) Damodhara Rao, M; KAU; John Thomas, Kthe final efficiencies are almost the same irrespective of the concentration of soil suspension. The particle size distribution of underflow material for different concentrations of soil suspension indicates a measure of separation efficiency of the filter. It was found that the percentage finer to coarser particles is almost the same for all the concentrations but for lower concentrations, fine particles have higher percentage of finer. This may indicate the efficient separation of fine particles in the case of lower . concentrations of soil suspensions. For the soil suspension of 300, 600, 900 and 1200mg/1 the percentage of particles finer than 0.075111111 are 0.86, 0.58, 1.96 and 4.05% respectively. The higher value of concentration for 300mg/1 indicates the better separation of finer particles.ThesisItem Open Access Storage studies on preservation of banana and its production(Department of Farm power Machinery and Energy, Kelappaji College of Agricultural Engineering and Technology, Tavanur, 2000) Sindu, Bhaskar; KAU; Ganesan, VThe primary objective of this study was to conduct shelf lite studies like vacuum packing and nitrogen packing on storage of banana and its products and to suggest optimum storage conditions. The study mainly concentrated on development of equipments for optimising the processing and storage conditions. A constant temperature frying pan was developed for optimising the frying temperature, duration and type of oil. The capacity of the constant temperature frying pan is 100 kg of raw banana per day of 8 h. A low cost set up for nitrogen packing was also developed. Vacuum packing as well as nitrogen packing can be done satisfactorily. Raw banana stored under vacuum cum refrigerated packing showed maximum shelf life up to 20 days without any quality deterioration. The chips fried in coconut oil at a temperature 115 QC for a duration 15 min stored under nitrogen packing showed best results followed by chips fried in coconut oil at a temperature 105 QC for 20 min under nitrogen packing. These results were on the basis of organoleptic evaluation. Jaggery coated chips and banana powder stored under nitrogen packing was the best among four treatments after storage of two months. The economic analysis showed the cost of entire operation for the processing of chips was Rs.57.5 per kg of chips. The moisture content of 'taw banana have significant effect on cooking duration therefore the moisture content of banana slices prepared for chips making should be standardised. The peeling and slicing operations are done manually. The speed of the labourers have considerable effect on capacity of constant temperature frying pan.