Loading...
Theses
Browse
8 results
Search Results
ThesisItem Open Access Development of an automatic cleaning mechanism for roof water harvesting(Department of Land and Water Resources and Conservation Engineering, Kelappaji College of Agricultural Engineering and Technology, Tavanur, 2016) Lakshminarayana, S V; KAU; Sathian, K KOne of the easiest and efficient way of water conservation to solve drinking water scarcity is rooftop water harvesting. However, the technology has some limitations with regard to its purification system. The commonly used sand and gravel filter is very prone to clogging and its cleaning is not an easy job. At the same time, the alternative upward flow mesh filter needs further improvement in cleaning efficiency and some hassle free drain cum back washing mechanism. Hence, a study has been taken up on the upward flow filter system to improve its filtration efficiency and incorporate an automated drain cum back washing mechanism. The study also included the performance evaluation of a first flush system when attached to the inlet side of the micro mesh filter. To evaluate the performance of the filter and first flush, inflow and outflow of the rooftop water samples were analysed for pH, EC, TDS, SAL and TSS parameters. In general, the PH, electrical conductivity, and TDS of the roof water samples were within the drinking water standards and the filter system was found to reduce TDS values. In the case of TSS, mostly the impurities were organic in nature and concentration varied between 220 to 280 mg/l, a level much higher than WHO and BIS standards. The 3 micron mesh filter is removing 100% of the organic TSS impurities. The filtration rate of this filter is about 0.37 lps at a hydraulic head of 1.5 m and hence suites to rooftop rain water harvesting. First flush system showed better cleaning efficiency when attached to the inlet side of the coarser micro mesh filters. Automatic flush developed for the removal of stagnant water with impurities were performing well by removing all the stagnant water and about 92 % of the impurities. It can be concluded that 3 micron mesh filter with automatic flush can function as a near fool proof mechanism for filtering rooftop rain wateThesisItem Open Access Soil water balance studies in subsurface drip irrigation for amaranthus(Department of Land and Water Resources and Conservation Engineering, Kelappaji College of Agricultural Engineering and Technology, Tavanur, 2016) Neetha Shaju; KAU; Priya, G NairSubsurface drip irrigation (SDI) is advanced drip irrigation where the tubing and emitters are buried beneath the soil surface. Field experiment was done at the instructional farm, KCAET, Tavanur. Experiment was aimed to optimize the depth of installation of laterals and spacing between laterals under subsurface drip system. This study also computed deep percolation from different layers with different lateral depths. Soil moisture was taken from different depths and horizontal distance and soil moisture contour maps were plotted. Results showed that moisture content increased with depth from the surface due to less evaporation loss. Also, amount of moisture was found to be decreased with time. Moisture content at the surface layer for 10 cm lateral was 14.5 per cent whereas the same for 20 cm lateral was 11.6 per cent due to surfacing. Moisture distribution pattern was uniform for lateral with 15 cm depth. Maximum values of yield were observed for the treatment T4, and then T1 (which have 15 cm and 10 cm lateral depth respectively). Highest water use efficiency was for treatment T4 with a value of 37.96 kg/ha-mm followed by treatment T1 with 34.6 kg/ha-mm. In statistical analysis, it was observed that, there were significant variations between treatments. Number of leaves was influenced by both spacing between laterals and depth of laterals. Stem girth was varied significantly by spacing between laterals. Both spacing between laterals and lateral depth had remarkable effect on crop height. Deep percolation was relatively less from the surface layers than from the deeper layers in higher lateral depths (i.e., 20 cm lateral depth). From this study, it is evident that treatment T4 (lateral spacing = 95 cm, lateral depth= 15 cm) has showed maximum response while considering moisture distribution, crop yield, biometric properties and deep percolation.ThesisItem Open Access Modification and evaluation of automated drip irrigation system(Department of Land & Water Resources and Conservation Engineering, Kelappaji College of Agricultural Engineering and Technology, Tavanur, 2016) Arjun Prakash, K V; KAU; Sajeena, SWater is the most valuable resource in the world and is playing a crucial role in daily activities of living beings on the earth. To meet the ever increasing demand, conservation and management of water resource is very important. Conventional methods of irrigation, like surface and subsurface flooding leads to scarcity of water, which can be reduced by adopting drip or trickle irrigation. Drip irrigation system can be controlled through different automation techniques. The present study was focused on the modification and evaluation of the existing cost effective automated drip irrigation system. In this study, calibration of capacitor type and conductive type moisture sensors were carried out in different soil types viz. black soil, coastal alluvium, forest loam, laterite soil and riverine alluvium. Field study was carried out with Hilton FI variety of salad cucumber under different irrigation and fertigation levels using solenoid valves and GSM modem technique. The automated drip irrigation system consists of two capacitor type and two conductive type soil moisture sensors, solenoid valves and water flow sensors. Total yield and crop growth parameters showed better performance under 100 per cent fertigation when compared with 70 per cent fertigation. Combination of 100per cent fertigation with 70 per cent irrigation also showed good results, whereas production was less in the case of 70 per cent fertigation with 70 per cent irrigation. The modified automated drip irrigation system is cost effective, portable, durable and can perform betterThesisItem Open Access Improvement of purification system for roof water harvesting(Department of Land and Water Resources and Conservation Engineering, Kelappaji College of Agricultural Engineering and Technology, Tavanur, 2015) Swatha, V S; KAU; Sathian, K KThe severity of water scarcity and the need of water conservation, appropriate to the situation, are well understood facts and do not require any further elaboration. Knowing the potential of rooftop rainwater harvesting in Kerala state, the government has introduced legistation making rooftop rainwater harvesting mandatory for all newly constructed residential and commercial buildings. However, the roof water harvesting techniques is crippled with the inefficiency of the commonly employed sand and gravel purification system. The major deficiency of the system lies in the difficulty in cleaning of the filter media. Though studies have been initiated with alternative purification methods, it warrants further modification and improvisation. Keeping this in mind, this M.Tech research work has been taken up to find solutions to the purification issues of rooftop rainwater. The major focus of the work was to develop more efficient micro mesh filter in combination with a first flush system. To evaluate the performance of the filter and first flush, inflow and outflow of the roof water samples were analysed for pH, electrical conductivity, TDS, TSS, metal concentration and microbial parameters. In general, the pH, electrical conductivity and TDS of the roof water samples were within the drinking water standards for the different types of roofs tested. Micromesh purification reduced these quality parameters to further lower levels (10 to 20 percentage). Major TSS load was organic and its concentration was far beyond the permissible limit. Filtration with first flush system could reduce 88 percentage of the organic impurities. Metal and microbial concentrations of the roof water were within the permissible limits, the micromesh filtration could reduce their presence further by about 10 to15 percentage. There is further scope for improving the efficiency of mesh filters by adopting mesh sizes lower than 25 micron for which the discharge of the filter would not be a constraint, as has been revealed by the study.ThesisItem Open Access Comparative evaluation of naturally ventilated polyhouse and rainshelter on the performance of cowpea(Department of Land and Water Resources and Conservation Engineering, Kelappaji College of Agricultural Engineering and Technology, Tavanur, 2015) Ajay Gokul, A J; KAU; Abdul Hakkim, V MA study was conducted in the Instructional Farm of KCAET, Tavanur, Kerala, during the period from August to December 2014 to compare the performance of cowpea grown under polyhouse and rainshelter in relation to open field cultivation. Cowpea variety Vellayani Jyothika, a trailing type legume released by KAU, was used for the study. Fertilizers were applied through drip irrigation system using venturi assembly. The variation of weather parameters such as maximum and minimum temperature, relative humidity, soil temperature and rainfall during the crop growth period was studied. Mean monthly values of temperature, relative humidity and soil temperature inside the polyhouse was higher than that in rainshelter and open field throughout the growth period. The maximum rainfall (360.7 mm) was recorded in the month of October and minimum rainfall (6.3 mm) was recorded in the month of December. Crop growth parameters such as plant height, internodal length, number of branches and time taken for flower initiation were noted during various crop growth stages for all the treatments. During all growth stages, the plant height and internodal length were significantly higher inside the polyhouse followed by rainshelter and open field. Among the different treatments, early flower initiation (39 days) was noted in the polyhouse. Yield parameters such as number of pods per plant, average length of pods and total yield per plant for each treatment were noted during various crop growth stages. The number of pods per plant was significantly higher in open field. Average length of pods inside polyhouse and inside rainshelter was higher than that in the open field. There was no significant difference in total yield of cowpea harvested from the observation plants under the three treatments. The maximum Benefit Cost ratio of 1.73 was obtained in the open field cultivation. Benefit Cost ratio of polyhouse and rainshelter were 1.06 and 1.34 respectively. Incidence of pests and diseases were also comparatively low inside the rainshelter and higher incidence of pests and diseases were noticed in the open field. From the results of the study it was evident that growing cowpea (Vellayani Jyothika) inside the rainshelter is more profitable than growing it inside naturally ventilated polyhouse.ThesisItem Open Access Design, development and evaluation of an automated drip irrigation system(Department of Land and Water Resources and Conservation Engineering, Kelappaji College of Agricultural Engineering and technology, Tavanur, 2014) Navneet, Sharma; KAU; Abdul Hakkim, V MThe present study was conducted to design, develop and evaluate an automated drip irrigation system working on the basis of soil moisture deficit and to establish the relationship between soil moisture content, electrical conductivity. The study involved fabrication of a soil moisture deficit based automation system and testing of the system under laboratory and field conditions. The system was tested and calibrated for automatic irrigation scheduling. As the soil started drying up, water content decreased and the conductivity reading in the data logger decreased. When the sensor readings reach the preset threshold level, the system gets automatically switched on. The irrigation setup was operated until the moisture reached the preset level of field capacity. Conversely, an increase the soil water content increased the conductivity. In this way, automation system continuously recorded fluctuations in soil moisture content under varying field conditions. Laboratory tests were conducted to evaluate the performance of the drip automation system in salt solution, sandy loam and laterite soils to develop the calibration curves. It was observed that there existed a significant correlation between the soil moisture content and electrical conductivity of sensors. Soil moisture sensors were evaluated with respect to the moisture content of sandy loam and laterite soils. In sandy loam soil, the values of maximum and minimum sensor output values were 17.5 to 3.3 mS/m and for laterite soil it was 15.1 to 2.4 mS/m. In the field evaluation using amaranths crop, the moisture distribution was more or less uniform near the soil surface soon after irrigation. The developed electrical conductivity based soil moisture sensors performed well in the laboratory study using sandy loam and laterite soils, but during field evaluation in sandy loam soil its performance was not satisfactory. In case of capacitor type soil moisture sensor, the performance was satisfactory in both conditions. Capacitor type soil moisture sensor performed well in sandy loam soil in the field evaluation. From the results of this study it can be concluded that capacitor type soil moisture sensor can perform better than electrical conductivity based soil moisture sensor for field use. The drip automation system developed was simple, precise, sensitive, light weight, cost effective in construction and fast responding. The speed of measurement, cheapness and portability are the key advantages and the system is easily adaptable for use with automatic logging equipment. There is scope for further studies on optimization of the electrode geometry and evaluation of electrical conductivity based soil moisture sensors with different fertilizer and chemical application.ThesisItem Open Access Development and evaluation of a solar powered automated fertigation system(Department of Land and Water Resources Conservation Engineering, Kelappaji College of Agricultural Engineering and Technology, 2016) Anjaly C, Sunny; KAU; Abdul Hakkim, V MAutomated fertigation system is a highly advanced system for water and fertilizer administration in irrigated agriculture. It promises the application of water in right quantity along with right fertilizer at right time, thereby reducing fertilizer loss and labour resulting in saving of money with the help of an automated mechanism. The present study was undertaken to develop a timer based automated fertigation system using an FIP and to evaluate the performance of the system. Field evaluation of the developed automated fertigation system was carried out by growing salad cucumber variety ‘Saniya’ in grow bags inside a poly house located at Agricultural Research Station, Anakkayam. A comparative evaluation was carried out between biometric observations and yield parameters of the two sets of crop grown inside the polyhouse, one fertigated automatically with the developed system and the other one with manual fertilizer application and a third group of plants grown in the open field with manual fertilizer application. Data collected was subjected to statistical scrutiny viz., ANOVA (Analysis of Variance) and Student-t test. The main crop growth parameters like height of the plant, days to first flowering, days to 50 percentage flowering, days to initial budding, days to first harvest and leaf area index were observed. Yield parameters viz. size of the fruit, number of fruits harvested per plant and average yield were recorded during the study. Values of all these parameters were found to be better for the crops grown inside the polyhouse with automated fertigation compared to the other two. The developed system operates using solar panel generating a power of 250 W on an average along with a battery, which makes the system operations possible up to 4.4 days without sunshine. Hence it can be concluded that the developed automated fertigation system can ensure better yield for salad cucumber variety ‘Saniya’ grown inside the polyhouse.ThesisItem Open Access Ground water resources modelling of a watershed using mudflow(Department of land and water resources & Conservation engineering, Kelappaji college of agricultural engineering & Technology, Tavanur, 2016) Sajeena, S; KAU; Kurien, E K
