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  • ThesisItemOpen Access
    Design, fabrication and testing of a power operated jab type paddy dibbler
    (Department of Farm Power Machinery and Energy, Kelappaji College of Agricultural Engineering and Technology, Tavanur, 1997) Maji Krishnan, G; KAU; Jippu, Jacob
    A power operated jab type paddy dibbler developed and tested at K.C.A.E.T, Tavanur is described. A cup feed type metering mechanism, discharged the seeds into the distribution wheel. Rotation of this wheel caused the transfer of seeds from the distribution wheel to the seed tubes. The to and fro motion of the plungers inside the five seed tubes closed and opened the port between the seed tran9fer tube and seed tube at predetermined intervals. A cam and follower arrangement fitted on the main shaft regulated the to and fro motion of the plungers. In operation, the rotation of the dibbler wheel caused the tip of seed tubes to make holes in the soil. At the time of penetration the plunger occupied a position farthest to the main shaft thus keeping the tip of seed tube closed. This prevented the entry of soil into the seed tube. After the seed tube has reached the maximum depth the plunger is moved up quickly transferring the seeds into the holes. The dibbler gave seed rates of 87.1, 74.6, 68.0, and 61.1 kg/ha at the speeds 0.788, 1.152, 1.530 and 1.778 km/h respectively in the field. It placed at an average 3-6 seeds in a hill at a depth of 4-4.2 cm. The number of seeds mechanically damaged was only 0.89 per cent and loss of viability due to mechanical damage was only 3.77 per cent. The average power required was 0.093 hp. Labour requirement was 60.68 man-h/ha. Cost of operation of this dibbler was Rs 86.0/h including the cost of power source. The jab type dibbler is convenient for use by both men and women.
  • ThesisItemOpen Access
    Developing and testing of a collector-cum-storage types solar water heater for domestic use
    (Department of Farm Power Machinery and Energy, Kelappaji College of Agricultural Engineering and Technology, Tavanur, 2000) Bijukumar, K; KAU; Mohammad, C P
    The present study was undertaken to desi~n and develop a collector-cum-storage type solar water heater of 30 litre capacity to supply hot water for domestic use. Five solar water heaters with different absorber plate positions were constructed. The storage tanks with dimensions of 67 xIl7 x 10 cm were made by using fibre glass, and the top of these storage tanks were covered using single plain glass plates of 71 x 51 x 0.4 cm size. The position of the absorber plate was varied by changing the width of the spacers (4 nos. at an angle of 400 with the side aluminium sheet), which connects bottom aluminium plate and top absorber plate. The absorber plate was of 65 x 45 cm size. The top face of the absorber plate was painted black to absorb maximum solar. radiation. The absorber plate positions were lcm, 3cm, 5cm, 7cm and 9cm from the top glass cover plate and were designated as SWHl 0, SWH30, SWH5.0, SWH7.0 and SWH9.0 respectively. The absorber plate position was optimized by testing the solar water heaters under two different test conditions. Solar water heater II (SWH3.0) outperforms other solar water heaters under the two test conditions. Maximum outlet temperature of 64°C af 3pm and maximum efficiency of 55.72% also at 3pm were observed in solar water heater 11. So it is optimized that the position of the absorber plate should be at 3cm from . the top glass plate. The solar warer heater can easily be handled by a single person since the weight is only 9.5kg. The operating cost per unit of thermal energy obtained withthe solar water heater was found to be 25 paise per kWh.
  • ThesisItemOpen Access
    Development of low cost electrostatic spray-charging system for liquid formulations
    (Department of Farm Power Machinery and Energy, Kelappaji College of Agricultural Engineering and Technology, Tavanur, 2016) Dipak Khatawkar, S; KAU; Dhalin, D
    The introduction of electrically charged sprays in agricultural application has become inevitable for better control on droplet transference with reduced drift and increase in application efficiency with less spray chemical requirements. In the present study was under taken to develop an electrostatic induction spray charging system as attachment to powered knapsack mist-blower. A high voltage generator was fabricated on the basis of Cockcroft-Walton voltage multiplier principle with input of 6 V DC battery to provide high voltage required at the developed charging electrode assembly (Model III, Model IV and Model V) for inducing electrostatic charge on spray droplets. As the existing (Model I) and redesigned (Model II) nozzle failed to give fine atomization, a self-atomizing hydraulic nozzle was developed for delivering the droplet spectrum required for effective electrostatic charge induction. The three working models (III, IV and V) were evaluated for charge to mass ratio (mC.kg-1) at five electrode potentials (1 kV, 2 kV, 3 kV, 4 kV and 5 kV), four electrode placement positions (0 mm, 5 mm, 10 mm and 15 mm) and five distances (50 cm, 100cm, 150 cm, 200 cm and 250 cm) from the nozzle. Model V with electrode voltage potential at 5 kV and EPP at 5 mm shown the maximum CMR value (1.088 mC.kg-1), followed by Model III (0.888 mC.kg-1) and Model IV (0.777 mC.kg-1) with same combination of variables. In contrast with commercial system (ESS-MBP90) it was observed that except at 50 cm distance from nozzle, Model V (at 4 kV and 5 kV) surpassed commercial system in CMR from 100 cm to 250 cm distance. To avoid air blast injury of plant, the nozzle has to be 100 cm to 150 cm away from the plant. The droplet spectrum of the developed system was analysed and observed that the size of droplets were 100 to 200 μm. The deposition efficiency of the developed system was on par with that commercial unit, and was within the range of 60 to 70 per cent. The developed system found to be cost effective and significantly consistent than the commercial system.
  • ThesisItemOpen Access
    Evaluation of physiological cost and subjective assessment of existing coconut climbing devices
    (Department of Farm Power Machinery and Energy, Kelappaji College of Agricultural Engineering and Technology, Tavanur, 2015) Hameeda Bindu, Vahab; KAU; Bini, Sam
    At present there are different models of coconut climbing devices available in the market. Most of the climbing devices safety and efficiency aspects are not being studied and needs to be comparatively evaluated and modified. In this study five coconut climbing devices were selected, those are Sit and climb type (TNAU model), Standing type (Chemberi model), KAU coconut palm climber (developed at KCAET), Kerasureksha (Model developed at ARS, Mannuthy) and CPCRI model coconut climbing device. Pertinent anthropometric dimensions of human subjects with reference to the dimensions and positions of the functional components of coconut climbing devices was identified and 35 different body dimensions useful for the design or redesign of coconut climbing devices were recorded by following standard anthropometric procedure. Ten subjects (five each for men and women) were selected, conforming to statistical requirements of anthropometric dimensions. The selected ten subjects were screened for normal health through medical and bio-clinical investigations which includes Electro Cardio Graph (ECG), blood pressure and bio-clinical analysis. Selected ten subjects were calibrated in the laboratory by indirect assessment of oxygen uptake. The relationship between the heart rate and oxygen consumption of the subjects was found to be linear for all the subjects. Then energy cost of operation of the selected coconut climbing devices were computed by multiplying the oxygen consumed by the subject during the trial period with the calorific value of oxygen as 20.88 kJ lit-1. Energy cost is comparatively less for KAU coconut palm climber with other models. Mean energy cost of male subjects during the operation of KAU coconut palm climber is 23.16 kJ min-1 and female shows 25.73 kJ min-1. Variation of heart rate and energy cost of both male and female for selected five models were statistically analyzed. Female subjects are significantly differed in both heart rate and energy cost on different coconut climbing devices and all the female subjects showed minimum heart rate while operating KAU coconut palm climbing device. But male subjects are shown any significant difference for both heart rate and energy cost. But they shows comparatively less heart rate for KAU coconut palm climbing device. The oxygen uptake in terms of VO2 max was minimum for KAU coconut palm climber (58.53 per cent) while it was 65.22 per cent for Sit and climb type (TNAU model) for male operators. Similarly for female subjects, minimum for KAU coconut palm climber (74.30 per cent). Sit and climb type (TNAU model) is difficult in operation compared with other devices. Major discomfort was happened in left thigh, right thigh, left foot and right foot. Based on these results it was found that KAU coconut palm climber and Kerasuraksha coconut climbing device were identified as more suitable for climbers than other climbing devices. Seating unit of Kerasuraksha coconut climbing device and pedal unit of KAU coconut palm climber were ergonomically comfortable for the climbing operator and developed a new model by incorporating the constructional behavior of both KAU coconut palm climber and Kerasuraksha coconut climbing device. Energy expenditure of new model for male is decreased by the rate of 10.8per cent when compared to Sit and climb type (TNAU model and with KAU coconut palm climber it is comparable. In the case of female subjects, Energy cost of new model was decreased by 7.8 per cent with Kerasuraksha coconut climbing device and 6.2 per cent with Sit and climb type (TNAU model) and it is comparable with KAU coconut palm climber. Mean VO2, VO2 max and work pulse of new model is 1.10, 58.16 per cent and 69.70 beats min-1 for male and for female it is 1.22, 73.45 per cent and 81.10 beats min-1 respectively. These values are comparatively less than value of other five models. The time required for climbing new model was 65.01 sec for male subjects which are less than other five selected coconut climbing devices and same trend for female also. The setting time of the new model was 65 sec while for KAU coconut palm climber it was 150 sec. Time was reduced by 56.67 per cent compare to KAU coconut palm climber
  • ThesisItemOpen Access
    Development of powertiller operated paddy reaper windrower
    (Department of Farm Power Machinery and Energy, Kelappaji College of Agricultural Engineering and Technology, Tavanur, 1997) Shiny, Lukose; KAU; Sivaswami, S
    A vertical conveyor reaper-windrower suitable for mounting on KAMCO 9hp powertiller was developed Kerala for the first time. After considering the maneuvrability, weight distribution, field capacity and power transmission, the 1.6m width vertical reaper was selected for the KAMCO powertiller and was locally fabricated. The complete rotavator unit was dismantled and a newly designed power transmission unit was fitted on the KAMCO powertiller. The handle was kept at an ergonomically suitable height of 1m. A combination frame was developed inorder to accommodate both the engine and the reaper at the most appropriate location to achieve the static and dynamic balancing during field operation after the removal of rotavator. The centre of gravity of the engine at the new location was 50mm in front of the wheel axle and at a height of 180mm from its original position. Field evaluation of the reaper was carried out during November and December, 1996 at Tavanur. The front mounted reaper- windrower was evaluated to find out the optimum engine speed and forward speed to achieve better harvesting and windrowing pattern, maximum field capacity and field efficiency with less harvesting losses were found out. For the recommended engine speed of 1200 to 1400rpm at low first and low second gears a forward speed of 0.53 to O. 94m per sec. was obtained in the field. The actual cutting width was 1.5m. The maximum field efficiency of 85 per cent was obtained for first gear when the engine rpm was 1200. Actual field capacity for this speed was 0.224ha per hr. It was seen that for the recommended engine speed between 1200 to 1400rpm a normal forward speed of (.53 to 0. 94m/sec was obtained with an average actual field capacity of 0.25 ha/hr and an average total grain loss of 1.9 per cent in the field. Downward handle reaction for this recommended speeds varied between 9 to 14 kgf at the time releasing the clutch or using the accelarator. By the use of powertiller reaper a labour saving of 82.5 per cent was obtained. The owner would get a monitory benefit of Rs.1210/ha while the farmer hiring the reaper would get a saving of Rs.830/ha compared to manual harvesting. The initial invest of the owner would be paid back within 2 years if he could hire it out for 1000hrs per year. The total weight of the unit is 451kg which is 34kg less than the original weight the powertiller with rotavator unit. Its overall dimensions are L:279S x W: 1650 x h: 1510mm and the total cost is Rs.1,16,500.
  • ThesisItemOpen Access
    Design fabrication and testing of an arecanut dehusker
    (Department of Farm Power Machinery and Energy, Kelappaji College of Agricultural Engineering and Technology,Tavanur, 1993) Febi Varghese; KAU; Jippu Jacob
    A power operated arecanut dehusker is designed, developed and its performance evaluated. The major parts are the hopper, feeder, lead plate, cutting blade, shearing roller, friction plate and scraper. The feeder receives the graded fruit from the hopper and delivers it on the lead plate. The fruit is compressed between the rotating shearing roller and the lead plate. The teeth on the roller peel off the husk and the kernel is ejected out through the slot on the lead plate and the husk removed. A single phase 0.5 hp motor operates the machine. From the studies, the optimum set - up of the machine for deriving maximum dehusking efficiency and Iower percentage of the number kernels damaged is at a speed of 35 rpm, blade angle of 600 and slot angle of 1400. At this set - up the machine gives an output of 9.0 kg dried fruit/h, with 84.5 per cent dehusking efficiency.
  • ThesisItemOpen Access
    Evaluation and modification of powertiller operated paddy reaper
    (Department of Farm Power Machinery and Energy, Kelappaji College of Agricultural Engineering and Technology, Tavanur, 1995) Selvan, P; KAU; Sivaswami, N
    The study on power tiller operated paddy reaper-windrower was taken up solve the problems of labour scarcity and uneconomic cost of cultivation of paddy. The 1.6 m vertical conveyer reaper-windrower was fabricated and was mounted with commercially available 8-10 hp air cooled Mistubishi power tiller. Improvements and modifications were carried out to make the unit suitable for harvesting of paddy in Kerala. The original engine chasis of the power tiller was replaced with a newly fabricated chasis on which both the engine and paddy harvester were mounted. Difficulties were experienced in starting and in operating the harvester when the drive was taken directly from the engine pulley to the cutterbar. Initialy the unit was operated with rotovator at the rear side. It was found difficulty in crossing the bunds, hence rotovator was removed. After detailed studies, an auxiliary gear box was designed and fabricated for transmitting power to reaper from the rotovator gear assembly. The rear rotovator was dismantled and the auxiliary gear box was assembled. For balancing, a counter weight of 35 kg was added in between the handles. The crop is cut by the reciprocating knife while passing through crop dividers, star wheels, pressure springs and is conveyed by a pair of lugged conveyer belts and is discharged as a neat windrow. Improvements and modifications were carriedout on most of the reaper components. Field evaluation of paddy harvester was carried out at KCAET Tavanur for two seasons. It was found that harvester has an effective cutting width of 1.55 m and an average field capacity of 0.02036 ha/hr. The pre harvest loss, sickle loss, shattering loss and total cutter bar loss were found to be 0.005 per cent, 2.43 per cent and 0.026 per cent respectively. The power tiller operated reaper-windower was found suitable for harvesting paddy both in wet as well as dry fields except the fully lodged crops. It is an appropriate machinery for harvesting paddy and is found economically and technically suitable for Kerala conditions. It was calculated that manual harvesting needs Rs. 1625/ha whereas power tiller operated reaper needs only Rs. 348/ha and thus achieved a saving of amount of Rs. 1277/ha. The savings of 186 man-hrs/ha achieved by the introduction of power tiller operated paddy reaper is a promising solution for the crisis of labour scarcity and the high cost of labour input in the paddy cultivation.
  • ThesisItemOpen Access
    Ergonomic investigations on hand arm vibration of brush cutter for the development of a vibration reducing aid
    (Department of Farm Power Machinery and Energy, Kelappaji College of Agricultural Engineering and Technology, Tavanur, 2016) Aswathi, K; KAU; Sureshkumar, P K
    Brush cutters are widely used in Kerala for weeding and clearing fields. While operating brush cutters, certain amount of vibration is transmitted to human body.Extended exposure to mechanical vibration can induce degeneration of the vascular and sensio-neural systems in the hand called hand-arm vibration syndrome (HAVS).The hand-arm vibration syndrome (HAVS) is a complex condition associated with vibration exposure and the use of hand-held vibrating machines. The vibration exposure of worker can be decreased by proper selection and maintenance of tool. To study the ergonomic aspects and hand transmitted vibrations of brush cutters, six subjects (3 male & 3 female) were selected who arehaving experience in operation of brush cutter.A suitable vibration reducing aid for brush cutters is designed and fabricated keeping the view that it should be capable of transmitting at least a part of the vibration produced at cutter head to the ground.It should be easily attached or detached from the brush cutters shaft.The material used for the vibration reduction aid should be light in weight and sturdy, so that it could be raised along with the cutter head by the operator. According to the conceptual design, a vibration reduction aid is developed and field tested. It consists of parts viz. curved arms, fixture to arms, quick fixing locks, ground rollers, rollers fixture and rubber grip. The brush cutter and vibration reducing aid is evaluated in the field with different cutter heads viz. nylon rope, 2 blade, 3 blade and circular blade. The experiment is repeated for 2-stroke and 4-stroke models of brush cutters operated by male and female subjects. The energy expenditure for brush cutter operation is calculated for two models of brush cutter for all subjects and compared. A statistical analysis is conducted using MSTAT software and found that the developed vibration reducing aid, blade and type of internal combustion engine have significant effect on vibration excitation in both right and left handles of brush cutters selected. The proposed method of evaluating occupational risk related to mechanical vibration exposure while working with brush cutter makes it possible to account the effect of attachment, cutter head and type of internal combustion engine. Subjective ratings like ODR, OER, OSR and BPDS also indicated significant effect of reducing vibration due to the vibration reducing aid.
  • ThesisItemOpen Access
    Modification and testing of a coleus harvester
    (Department of Farm Power Machinery and Energy, Kelappaji College of Agricultural Engineering and Technology, Tavanur, 2015) Younus, A; KAU; Jayan, P R
    Coleus (Solenostemon rotundifolius) commonly known as Chinese potato, is a major tuber crop of Kerala used for vegetable purpuse, raised purely as a rain fed crop from June to December. Manual harvesting of coleus is done by using spade, which is very tedious and time consuming, bruises and injuries. To overcome these problems and decreasing the cost of harvesting operation, a self propelled coleus harvester was modified and field tested. The developed coleus harvester was an attachment to a mini tiller, which consists of a prime mover, a digger, rotary blade, and driven wheels. As and when the tiller moves, digger pierced into the soil at a depth of 10-15 cm to digout the rhizomes that lie inside the soil. The uprooted coleus were then pushed out by means of the rotary splasher. The scattered coleus lying in the raised bed were collected easily and hence the harvesting becomes easier and faster. The rotary slasher are the rotating blades attached to the rear side of the tiller which was modified in such a way that they were removed and rubber flaps of 75 x 75 x 0.3 mm were fastened to the shank of the rotary blade. A set of larger wheels were designed and fabricated separately with diameter of 80 cm. The performance of the modified coleus harvester was compared with respect to time, fuel consumption, capacity and percentage of damage of coleus separately with flat and angular tynes. The performance on time taken (s) to dig out coleus with 6- tyne and 10 - tyne flat and angular digger revealed that while using 6 - tynes, the time taken and fuel consumption (ml) were highest in beds of 70 x 30 cm, whereas minimum were in the bed size of 50 x 30 cm The capacity of coleus harvester with 6 -tyne and 10 - tyne flat and angular diggers were determined. It is noted that the uprooted was the highest in beds of 50 x 20 cm, whereas minimum weight uprooted was in the bed size of 50 x 40 cm when operated with 6 flat tynes. When 10 angular tynes were used, it is noted that the weight (kg) of coleus uprooted was the highest in beds of 70 x 30 cm and minimum weight uprooted was in the bed size of 50 x 20 cm. Thus the average capacity of the harvester was observed as 1069 kg.h -1.The percentage of damage of coleus observed was the highest in beds of 70 x 30 cm, whereas minimum was in the bed size of 70 x 40 cm while using 6 - tynes. Performance analysis of a commercial harvester (TNAU ginger harvester) indicated that the vibrating mechanism provided was useful to obtain the coleus in clumps after harvest. In field operation it was not possible for uprooting coleus in the beds having more than 30 cm height. The field capacity of the modified coleus harvester is 0.057 ha.h-1. At the present wage rate of Rs 500 per day, the total cost of operation by manual method is about Rs 31,250 per ha. Whereas harvesting by the harvester, the total cost of operation is Rs 7680 per ha. Hence the savings over conventional method is Rs 24,470 per ha. The field efficiency of the harvester was calculated as 95 %. The performance of the machine was tested with two types of tynes - flat and angular with 6 - tyne and 10 - tynes. Time to harvest one bed of crop, fuel consumed for harvesting one bed, capacity of the harvester and percentage of damaged tubers were calculated. Among two types of flat tynes, the minimum time for harvesting one bed was achieved using 6 - tynes (21.66 min) and its fuel consumption was also less compared with 10 - of tynes. The average capacity of the machine was obtained as 1061 kg h-1.Percentage of damaged tubers was 5% corresponding to 6 - tynes. In the case of angular tynes, the shortest time for harvesting was achieved with 10 - tynes and the corresponding fuel consumption was 19 m1. The percentage of damaged tubers was 8% with 10 - tynes and was little high compared with 6 - tynes.