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ThesisItem Open Access Thermal modeling and performance evaluation of north wall reflective multi-tray cabinet solar dryer(Punjab Agricultural University, Ludhiana, 2019) Spall, Saloni; Sethi, V.P.In this study, an innovative design of front loaded multi-rack tray (MRT) solar cabinet dryer with north wall reflector (NWR) having two shelves and four trays (of 125 × 75 cm each) is presented for efficient drying operation at domestic and small scale commercial level. The total drying area of the polycarbonate sheet covered MRT solar cabinet dryer is 3.75 m2. Aluminized reflector sheet is used on the north wall of the dryer to enhance the solar radiation capture by utilizing the reflective component of the beam radiation particularly in winter conditions when conventional solar dryers are not able to perform the drying operation due to smaller solar radiation availability at latitudes of 30°N and above. The modified global solar radiation was developed to determine the effect of NWR onto the solar radiation capture by the dryer. A thermal model was also developed by writing energy balance equations for dryer chamber air (Tch) and crop surface temperature (Tc). Mathematical equations were solved using Modified Euler’s method by writing a computer program on FREEMAT software. The experiments were conducted under natural convection as well as under forced convection mode with and without using the NWR during winter and summer conditions in order to ascertain the effect of NWR on the performance of dryer. The validation of predicted results were performed using the experimental data generated in winter and summer conditions at Ludhiana climate (30.56°N latitude), India. Performance parameters such as; total heat loss coefficient, useful heat gain and thermal efficiency of the MRT solar cabinet dryer were also computed and compared with that of conventional dryer without using the NWR during winter as well as in summer. The results obtained showed that by using NWR, 37.5% solar radiation capture is enhanced in January month (at 30.56°N latitude) resulting in 4-7°C and 2-5°C higher chamber air temperature under natural and forced convection modes respectively. The total reduction in drying time for carrot drying was observed as 17.8% and 14.3% under natural and forced convection modes respectively by using NWR. The predicted and experimental values for crop surface and chamber air temperature were successfully validated with RMSE and 2 values ranging between 1.6 to 4.9. The Wang & Singh and Logarithmic drying models showed best adequacy of fit due to maximum value of R2 (0.991 to 0.999) and least value of SEE (0.002 to 0.004).ThesisItem Open Access Performance evaluation and analysis of forced draft paddy straw bale combustor for heating applications(Punjab Agricultural University, Ludhiana, 2018) Biswajeet Singh; Sethi, V.P.In this study, performance evaluation and analysis of predesigned forced draft paddy straw bale combustor (FDPSBC) furnace with intermittent pilot fuel injection system (PFIS) and embedded heat exchanger for generating high temperature flue gas for water heating and utilizing heat of generated flue gas and hot water to heat the greenhouse through the predesigned flue gas heat sink pipe network (FGHSPN) and hot water heat sink pipe network (HWHSPHN) is presented. Complete combustion of compressed bale of 20kg is achieved with the use of PFIS which delivered 1.5ml of diesel after every 3 min to maintain the flame sustainability.Stainless steel heat-exchanger has 62L water holding capacity circulating at the rate of 36 litre per min using the heat of flue gas and has the capacity to heat 1000L of water within three hours. Heat of combustion (>90% combustion efficiency)was utilized to generate flue gas at 350°C and hot water above 65°C applied to 100 m2area greenhouse heating located at Punjab Agricultural University, Ludhiana (30.56°N), Punjab, India by the predesigned two heat sink pipe networks; FGHSPN andHWHSPN laid inside the greenhouse for transfer of heat by radiation and free convection modes. Heat transfer models were developed to carry out the heat transfer analysis of combustor furnace, FGHSPN and HWHSPN. Developed mathematical models showed that insulation provided inside the combustor furnace reduced the heat loss by 91.7% through the combustor furnace wall whereasFGHSPN performed much better as compared to HWHSPN and was able to transfer 9.6 kW (74%) whereas HWHSPN could transfer 3.38 kW (26%) of heat respectively out of the total heat (12.98 kW) generated by both the networks to maintain the greenhouse air temperature 10°C higher than the ambient air temperature after sunset hours as validated by experimental trials conducted on 29 of November,2017 with a RMSE of 3.44.ThesisItem Open Access Development of crop coefficient curve for greenhouse cucumber grown in soilless media(Punjab Agricultural University, Ludhiana, 2018) Goyal, Pooja; Sharda, RakeshThe knowledge of crop coefficients (Kc) is necessary to estimate crop water requirements under the given growing conditions. The lysimeters are the best way for developing local Kc values. A study was undertaken to develop a weighing type lysimeter for cucumber crops grown in soilless media and hence, develop crop coefficients under greenhouse conditions. A precision weighing system based on load cell technology was used as a lysimeter. The crop was raised in growbag containing cocopeat and it was placed on top of the weighing mechanism inside the greenhouse. The irrigation was supplied via drip method and the drained water was collected for each day until the end of the crop growth period. The Actual evapotranspiration (ETc) was measured directly from the weight changes occurring at the lysimeter on a daily basis and the reference evapotranspiration (ETo) was calculated using FAO-56 Penman Monteith Equation (PME) using metrological variables i.e. temperature, relative humidity, wind speed and incident radiation both inside and outside the greenhouse. It was found that the average temperature and relative humidity values inside were greater than that of the outside conditions indicating that the greenhouse gives a greater range of temperatures and is more humid as compared to outside conditions. Also, the incoming radiation values inside the greenhouse were only 24-60% of that of the outside because of the presence of cover and shade net inside the greenhouse. The placement of the lysimeter inside the greenhouse affects the amount of water consumed by the crop. The average ETc from the lysimeters was 405.77mm for entire crop growth period of cucumber. The Kc values for different stages of the crop growth were 0.26 for initial stage (10 days), 0.26- 1.01 for development stage (20 days), 1.01 for mid-stage (40 days) and reduced from 1.01 to 0.69 for the end stage (10 days).ThesisItem Open Access Development of Relationships between Spectral Reflectance Data and Selected Biotic-abiotic Stresses in Cotton Crop(Punjab Agricultural University, Ludhiana, 2018) Soni, Rishabh; Singh, S.K.The present study was conducted to develop the relationships between spectral reflectance data and biotic-abiotic stresses in cotton crop. Four levels of urea application with rate of 225, 275, 325 and 375 kg ha-1 were applied in experimental plots. Row to row spacing for cotton crop were kept as 67.5 and 80 cm for the experiment. All the plots for the experimental field were georeferenced using GPS device. Data was collected at various growth stages of cotton crop using drone mounted cameras and Green Seeker for computation of variations in NDVI at different nitrogen levels. NDVI obtained from different sensors were increasing from vegetative stage (Mean NDVI = 0.454) till bud formation stage (mean NDVI = 0.7089) and decreased at boll opening stage (mean NDVI = 0.5232) till maturity stage (mean NDVI = 0.1432) of cotton crop. It was evident from the regression analysis that NDVI values obtained from NIR+R camera and Green Seeker had a good relationship having R2 = 0.74. Study also revealed that when mean insect population varied from 7.18 to 23.027 mean NDVI values obtained from NIR+ R camera after image processing varied in the range of 0.477 to 0.5441 and mean NDVI obtained from Green Seeker varied from 0.801 to 0.831. It was also found from the spatial maps and drone imagery that part of crop having more vigour, NDVI values in the vegetative stage was most affected by whitefly attack.ThesisItem Open Access Development and evaluation of direct paddy seeder in puddled field(Punjab Agricultural University, Ludhiana, 2018) Manoj Kumar; Dogra, RituPresent research was conducted to evaluate and develop a direct paddy seeder with use of pregerminated paddy seeds. For this three different metering mechanism were selected based on results of different studies performed on paddy sowing. An assembly of these three metering mechanism viz. fluted roller (containing 10 no of flutes on a 5 cm diameter shaft), cell type (10 cells grooved around a circular plate having 13 cm diameter), inclined plate (24 U shaped cells provided on an 18cm diameter plate) was developed and tested under laboratory condition. In the lab testing the metering mechanism assembly was tested for missing index (%), multiple index (%) and seed damage (%). The assembly was tested at three different forward speed viz; 2.5, 3.0 and 3.5 kmh-1 and three pregermination level of seeds viz; 24 hour soaked, 24 hour pregerminated and 36 hour pregerminated paddy seeds. On the basis of data analysis from lab study best suitable set for direct seeding of pregerminated seed in puddled feed was found to be inclined plate metering mechanism operating at 2.5 kmh-1 for 24 hour pre-germinated seeds. Keeping in mind the above suitable set for direct seeding a self-propelled 8 row direct paddy seeding planter was developed and fabricated with recommended row to row and hill to hill spacing. For field evaluation of planter hill to hill spacing, no of plants per square meter and germination count were measured for two different soil (ST1 and ST2) and taking two different hopper fill level as ½ filled hopper(F1) and ¾ filled hopper(F2).ThesisItem Open Access Development and Evaluation of Refraction Based System for Dehydration of Potato(Punjab Agricultural University, Ludhiana, 2018) Zalpouri, Ruchika; Preetinder KaurThe present study was conducted to develop and evaluate a refraction based system for dehydration of potato. Refraction based drying system was developed in Pilot plant, Department of Processing and Food Engineering, Punjab Agricultural University. The potatoes were peeled, cut into quarters, hot water blanched and immersed in 0.2% KMS solution for 15 min. After pretreatment, the potatoes were processed into puree and a known amount of distilled water was added to the puree to achieve desired TSS levels. The potato puree was dried by different drying methods viz. convective tray drying and refraction based drying system. The drying experiments were carried out at different TSS (8, 10 and 12º Brix), different blanching time (3, 4 and 5min) and at varying drying temperature 50, 60 and 70°C in convective tray drying and 70, 80 and 90oC in the refraction based drying system. It was observed that the physical properties of potato flakes were significantly affected by blanching time (p< 0.05). The moisture content ranged from 6.16-1.57% (db) and 7.61-3.46% (db) of potato flakes dried in refraction based drying system and convective tray dryer. Color values varied significantly (p<0.05) with respect to the drying method. Response Surface Methodology was used for optimization of process parameters. For refraction based drying system, the optimum operating conditions for drying temperature, blanching time and TSS were 70.00°C, 5.00 min and 11.54°Brix. At optimum condition, the values of responses were as follows protein content (31.66 mg/g), starch content (144.04 mg/g), reducing sugars (0.75 mg/g) and total sugars (6.25 mg/g) of dried potato flakes. For convective tray drying, optimum operating conditions for drying temperature, blanching time and TSS were 50.00°C, 4.23 min and 12.00°Brix. At optimum condition, the values of responses were as follows protein content (19.40 mg/g), starch content (16.47 mg/g), reducing sugars (0.94 mg/g) and total sugars (6.41 mg/g) of dried potato flakes. After considering all the parameters, it was found that refraction based drying system was more efficient as compared to the convective tray dryer.ThesisItem Open Access Development and evaluation of energy efficient tunnel dryer for chilli(Punjab Agricultural University, Ludhiana, 2018) Harmanpreet Kaur; Sharma, S.R.The study was conducted to develop and evaluate an energy efficient solar tunnel dryer. The dryer had dimensions of 12 X 8 X 4 m made of galvanized steel pipes and covered with 200µ thick polyethylene sheet having anti-mist and anti-drip properties. Three turbine fans were installed at the roof top of the dryer to provide natural ventilation. The performance evaluation of developed dryer was done for drying red chillies (CH-27). The maximum temperature recorded inside the dryer was 78°C which was 60.2 % higher than the corresponding ambient air temperature of 47°C. The corresponding relative humidity was 9.6 % against ambient air relative humidity of 21 %. The drying behaviour of pretreated red chillies was studied and colour of dried chilli was measured. The final moisture content ranged from 2.07% (d.b.) to 8.54% (d.b). In solar tunnel drying technique, the maximum drying time was found to be 31 sunshine hours for control whole chillies against 45 sunshine hours in open sun drying whereas the minimum drying time was found to be 12 sunshine hours for chemically treated chopped chillies against 15 sunshine hours in open sun drying. Also quality of chilli powder after grinding dried chillies was determined in terms of colour, colouring matter, capsaicin content and oleoresin content. Solar tunnel drying technique was much better than open sun drying technique in terms of drying behaviour and quality parameters. Solar tunnel dryer was found to be economical with pay-back period of 2.5 months and cost-benefit ratio greater than 1.ThesisItem Open Access Development of Therapeutic drinks from herbs(Punjab Agricultural University, Ludhiana, 2018) Ekaspreet Kiran; Sachdev, Poonam A.The present study was carried out with the objectives to standardize the process of preparation of therapeutic drinks, to analyze the effects of the developed drinks on human health and to study about the shelf life stability of drinks. The herbs selected for the study were mint leaves, curry leaves, coriander, sweet basil leaves, aloe vera and stevia. The raw herbs had an appreciable phytochemical profiles with mint having the highest values. Herbal extracts were prepared by grinding the herbs with adequate amounts of water ensuring complete extraction. Response Surface Methodology was used for establishing the relationship of responses (Antioxidant activity, Total phenols, Ascorbic acid and Overall acceptability) and design variables (extracts of mint, coriander, curry leaves for mint based drink and extracts of sweet basil, coriander and curry leaves for sweet basil based drink), and to optimize the blends using Box-Behnken design (BBD). The final optimized mint/ sweet basil based drink contained the following proportions: mint/ sweet basil extract (10%), coriander (15%), curry leaves (65%), aloe vera juice (10%) and stevia powder (0.2%). The formulated drinks were successful in maintaining healthy lipid profiles, serum uric acid levels and blood pressure. During storage period, the physicochemical properties (TS, TSS, acidity, and pH) changed non-significantly (p≤0.05), whereas phytochemical parameters and antioxidant activity decreased significantly (p≤0.05). It could be concluded from the research that the herbal based therapeutic drinks were prepared that contained appreciable phytochemicals with high amount of antioxidants.ThesisItem Open Access Delineation of Groundwater Potential Zones in District Ludhiana(Punjab Agricultural University, Ludhiana, 2018) Gurkaranbir Singh; Jain, A.K.With the increased demand for water because of urbanization, agricultural expansion and increasing population, groundwater resources are attaining more attention mainly in semi-arid and arid regions. Integration of geographical information system (GIS) along with other scientific techniques for the exploration of groundwater resources has become a breakthrough in the field of groundwater research, which assists in assessing, monitoring, and conserving groundwater resources. In the present study, the fence diagram of district Ludhiana has been developed using Rockworks software by studying the lithology of 171 boreholes to identify the groundwater bearing zones for future development of groundwater resources. The lithologic sections of the area (district as a whole as well as at block level) revealed two distinct features viz. sand and clay. Few clay layers were depicted intervening the multiple aquifers. The multiparametric data comprising aquifer thickness, aquifer permeability, water levels at different locations, stage of groundwater development, water level elevations and groundwater quality for irrigation purposes was spatially analyzed and integrated on a GIS platform to generate thematic maps. By integrating these maps, four groundwater potential zones have been delineated viz. poor, moderate, good and very good as per the assigned weights. Only 11.6 percent of area within the district was found with water table depth less than 10 m i.e. suitable for use of horizontal centrifugal pumps. It was inferred that around 591.83 km2 (15.7%) of the area in the district falls under the category having good groundwater potential zones whereas about 2916.21 km2 (77.5%) area was categorized as moderate groundwater potential zones and only 251.46 km2 (6.70%) of the area lied in poor groundwater potential zone category, especially in the central part of Ludhiana district. There is a need to reduce the groundwater extraction and encouraging water harvesting and artificial groundwater recharge in addition to crop diversification in poor groundwater potential zones, Based upon the analysis, further increase in extraction of groundwater was not recommended in this area. The study will be helpful in better planning and management of groundwater resources.