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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 Restricted 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 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 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 Restricted Refinement and evaluation of sugarcane trench planter to suit local conditions(Punjab Agricultural University, Ludhiana, 2018) Mohit Kumar; Dogra, BaldevTrench planting of sugarcane is being popularized by PAU as it gives better net returns, requires less water and management to avoid cane lodging is easy. At present, trench planting is practiced by making trenches using tractor operated trencher and remaining operations are done manually involving 200-250 man-h/ha. To reduce labour requirements, no such machine is being utilized by farmers in Punjab for planting sugarcane in trenches. There is shortage of labour Therefore, a sugarcane trench planter, which was commercially available in Uttar Pradesh, was modified according to suit local condition of Punjab to bridge this mechanization gap and thereby increasing the level of mechanization in Punjab. The preliminary evaluation of sugarcane trench planter was carried out at three different cutting rollers peripheral speeds (0.93 m/s, 0.81 m/s and 0.69m/s) and three forward speeds (2.26 km/h, 2.6 km/h and 3.0 km/h) on three varieties of cane (Co118, CoPb93 and CoJ-85). Thereafter, the field evaluation of modified sugarcane trench planter was carried out by selecting one cutting rollers peripheral speed 0.69 m/s and two forward speeds (2.26 km/h and 3 km/h) on same three varieties of cane (Co118, CoPb93 and CoJ-85). The selected dependent variables were cane length, cane diameter, set length, bud damage, set damage, number of set cut, overlap/ gap and germination count. The observed data was statistically analyzed by using statistical software ´SPSS`. The average cane length observed during field evaluation in Co118, CoPb93 and CoJ-85 was 212.33, 193.80 and 173.68 cm respectively. The average cane diameter observed during field evaluation in Co118, CoPb93 and CoJ-85 was 2.65, 2.35 and 2.73 cm respectively. Set length increased with the decrease in diameter of cane and cutting roller peripheral speed. Bud damage increased with the increase in cutting roller peripheral speed. Bud damage in variety Co118 was higher due to relatively more toughness of cane. Number of set cut increased with the increase in cane length and decrease in set length. Average overlapping decreased with the increase in forward speed. Practically no set damage was observed. Germination percentage on left side of trench observed in Co118, CoPb93 and CoJ-85 was 50.71%, 43.00% and 48.50% respectively, whereas, on right side of trench observed was 48.11%, 38.68% and 43.15% respectively. Germination of cane observed by machine planting was more than the conventional planting. There was 20 to 30% reduction in cost of planting and 55 to 60% reduction in labour cost as compared to conventional method.ThesisItem Restricted Modeling and optimization of extrusion process for utilization of vegetable waste(Punjab Agricultural University, Ludhiana, 2018) Choudhary, Kanupriya; Alam, M.S.Investigations were carried out to determine the best blanching pre-treatment and drying method for the development of dried radish leaves and pea pods (vegetable waste; VW) powder. The experiments were conducted using completely randomized design (CRD) by varying the blanching pre-treatments viz. hot water (HB), potassium metabisulphate (KMS), citric acid (CB) and drying methods viz. sun drying , solar drying and convective drying ( 55, 65 and 75°C). All the results were statistically analysed to estimate the significant difference between blanching pre-treatments and drying methods on the basis of physico-chemical quality attributes namely drying time, equilibrium moisture content, amino acid content, lignin content, crude fibre, color change and overall acceptability. The best quality dried vegetable waste powder was utilized in development of vegetable waste incorporated soy-cereal based product. Rice based extruded product were developed by replacing the base material (rice) with vegetable waste (VW)-soy powder (SP) mixed in equal proportion. The vegetable waste i.e. Radish leaves and pea pods powder mixed in equal proportion. Response surface methodology (RSM) was employed for optimization of extrusion process using four factor, three level Box-Behnken design. The extrusion process parameters i.e. VW-SP proportion (%), feed moisture content (% wb), die temperature (°C) and screw speed (rpm) for rice based extrudates were optimized for the responses namely bulk density (BD), specific mechanical energy (SME), expansion ratio (ER), water absorption index (WAI), water solubility index (WSI), protein content (PC), crude fibre (CF), hardness (H), color change (CC) and overall acceptability (OA). In addition to the optimization of extrusion process the modeling of extrusion process variables by using RSM and genetic algorithms (GAs) was done. The developed models were fitted to the extrusion data and their adequacy of fit was investigated. The hot water blanched radish leaves, convectively dried at 65°C was found to be best for utilization in the extruded product. The untreated samples (UT) of pea pods dried convectively at 75°C was found to be best for utilization in the extruded product. For rice based extrudates the optimum values of process parameters obtained by using RSM were: 35% VW-SP (i.e. 65% rice proportion) with 13.17% feed moisture content, 152.29°C die temperature and 360.42 rpm screw speed. Results obtained from RSM and GA were comparable. The vegetable waste and defatted soy flour can be successfully incorporated @ 35% i.e. 17.5% vegetable waste i.e. 8.75% radish leaves powder, 8.75% pea pods powder and 17.5% defatted soy flour powder.ThesisItem Restricted Impact of different irrigation methods on microbial activity in pea and chickpea(Punjab Agricultural University, Ludhiana, 2018) Singhal, Neha; Siag, MukeshField experiment was conducted in winter seasons of 2016-17 and 2017-18 at PAU, Ludhiana to study the impact of different irrigation methods on microbial activity in pea and chickpea. Pea var. PB-89 and chickpea var. PBG-5 were grown under five types of irrigation treatments. The treatments were drip irrigation in crop grown on plain (T1), drip irrigation in crop grown on ridges (T2), flood irrigation (T3), furrow irrigation (T4) and rainfed crop (T5). Growth parameters of plant height and leaf area index were recorded significantly higher under drip irrigation treatments. Symbiotic traits as number of nodules per plant and dry weight of nodules were recorded similar under different irrigation treatments but significantly more than rainfed treatment. However, leghaemoglobin content of nodules was found significantly more under drip irrigation. Microbial population of bacteria and Rhizobia were found non-significant but population of fungi and p-solubilizer bacteria and dehydrogenase activity of soil were significantly higher in drip and furrow irrigation. Significantly higher yields were found in drip irrigation treatments with maximum values under T1 for both the crops in both years and minimum values were observed under T5. A constant moisture regime was maintained in T1 and T2 which resulted in increased microbial activity and yield, while fluctuating moisture content under flood and furrow and deficit moisture content under rainfed treatment adversely affected yields. It may be concluded that drip irrigation positively impacts symbiotic traits and microbial activity which leads to better growth and yield of pea and chickpea crops.ThesisItem Open Access Development and evaluation of an engine operated walk type drop down sprayer for cotton crop(Punjab Agricultural University, Ludhiana, 2018) Dhaliwal, Ranjot Singh; Narang, M.K.An engine operated walk type drop down sprayer was developed for spraying on cotton crop. The developed sprayer had eight nozzles. Boom was developed in T-shape. Six nozzles were attached on vertical part of the boom with three nozzles spraying in left horizontal direction and other three spraying in right horizontal direction. The boom was mounted on a wheel hand vehicle. Nozzle selected for the sprayer was tested under laboratory conditions under different fluid flow pressures (7.5, 10 and 12.5 kg/cm2). The spray width, spray angle and discharge rate of the nozzle were noted. The discharge rate increased from 611.47 ml/min to 829.53 ml/min; Spray angle increased from 75.7 to 83.0 degrees and swath width varied from 85.1 to 99.8 cm with increase in pressure from 7.5 to 12.5 kg/cm2. The sprayer was evaluated in the field at 10 kg/cm2 for three different forward speeds (1.5, 2.0 and 2.5 km/h) and three different plant height of cotton crop (1.0, 1.3 and 1.75 m) at Research Farm of the Department of Farm Machinery and Power Engineering, PAU, Ludhiana The spot size, area covered, droplet density and field capacity were recorded and analyzed. The droplet density varied from 185.67 to 386 drops/cm2 for 1.5 km/h and at forward speed of 2.5 km/h, the droplet density varied from 53.33 to 286 drops/cm2. The maximum field capacity was found to be 0.16 ha/h at forward speed of 2.5 km/h and at plant height of 1.0 m. The bioefficacy of the developed sprayer was also evaluated at Krishi Vigyan Kendra, Goneana and at farmer’s fields in village Goneana, district Shri Muktsar Sahib at three levels of forward speed of 1.5, 2.0 and 2.5 km/h and at three heights of crop i.e. 1.0, 1.3 and 1.75 m and compared with the knapsack sprayer. The population of whitefly was recorded before spray and after three, seven and ten days of spray. The maximum percentage reduction over control was found at forward speed of 2.0 km/h and at plant height of 1.0 and 1.3 m.