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Author: Sandeep Kumar × End date: 2024 × Start date: 2020 × Type: Thesis ×
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    ThesisItemOpen Access
    Experimental investigation of thermo- hydraulic performance of rotating packed bed using air-water System
    (G. B. Pant University of Agriculture and Technology, Pantnagar, 2022-04) Sandeep Kumar; Murthy, D. S.
    Rotating packed bed (RPB) has a great potential for process intensification in thermal systems. However, the available literature is only focused on its mass transfer aspects and no study shows its heat transfer aspects. In rotating packed bed, the water flows outwards from the inner eriphery of a rotating rotor by centrifugal action and air travels inwards from the outer periphery by imposed pressure gradient making a counter current interaction with each other. The rotation of the rotor gives control over the water distribution unlike in conventional columns where gravity is the only driving force. In present work, rotating packed bed (RPB) have been explored for process intensification in thermal systems using air-water as working fluids. The thermo-hydraulic performance of rotating packed was carried out considering the air flow rate range varying from 0.007625 kg/s to 0.020175 kg/s, water flow rate varies from 0.033 kg/s to 0.133 kg/s and rotational speed considered is 0-2000 rpm. The thermal performance parameters such as cooling range, approach, water evaporation rate, heat transfer rate, Merkel number, and effectiveness for the RBP were experimentally evaluated for the given airflow rate, water flow rate and water inlet temperature (35, 40, and 45°C) and rotational speed. The optimum result for all the thermal performance parameters was observed at 1200 rpm. At the optimum condition, the observed value of cooling range was 15 ̊C, the value of approach was 12.2 ̊C, water evaporation rate was 0.000904 kg/s, effectiveness was 0.49 and the Merkel number was 0.426. The results were found to be in agreement with CTI (Cooling Technology Institute) performance curve charts, confirming the feasibility of RPBs to be used as thermal systems.
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    ThesisItemOpen Access
    Comparision of STCR and GRD approach for fertilizer recommendation in maize (Zea mays L.) - wheat (Triticum aestivum L.) crop rotation in North Western India
    (G.B. Pant University of Agriculture and Technology, Pantnagar, District Udham Singh Nagar, Uttarakhand. PIN - 263145, 2022-10) Sandeep Kumar; Shrivastava, Ajaya
    A field experiment was started since 2018-19 in the D7 block of Norman E. Borlaug Crop Research Centre of G. B. Pant University of Agriculture and Technology, Pantnagar. This thesis work is presented for the year 2021-22, on a comparison of soil test crop response and the GRD approach for fertilizer recommendation in maize–wheat crop rotation. For this experiment a hybrid maize variety (P3401) grown in the kharif season of the year 2021 and a wheat variety (HD 2967) grown in the rabi season of the year 2021-22. The experiment was carried out with three replications and nine treatments in a randomized block design and used treatments were control (T1), GRD (T2), STCR target yield (inorganic mode) (T3), STCR INM mode (T4), 75% STCR dose of N (inorganic mode) + green manure (T5), 50% STCR dose of N (inorganic mode) + green manure (T6), 75% RDN + green manure (T7), 50% RDN + green manure (T8) and FYM + green manure + urd intercropping (T9). It was observed that the residual impact of green manure (Sesbania) was seen only on the wheat crop during the kharif season because the crop was grown on-site, cut and incorporated into the soil during this time period only. There was only intercropping of urd between the rows of maize crops. The grain and straw yields for each plot were recorded after harvest. The plants and soil samples were collected at the end of each cropping season and analyzed according to standard methods. The experiments revealed that both inorganic fertilizers and organic manures (FYM and green manure incorporation) had no significant impact on soil pH and EC. STCR-based approach improved the mineralization of nitrogen, the extraction of phosphorus and the extraction of potassium from the soil. There was a variation in the maize yield between 29.33 q ha-1 and 57.47 q ha-1 during kharif 2021. Wheat grain yields ranged from 28.61 q ha-1 to 49.39 q ha-1 during rabi 2021-22. The crop had higher grain yields and nitrogen, phosphorus and potassium uptake after using 100% STCR-based fertilizers with FYM @ 10 t ha-1. A higher percentage of target yield was also achieved under the STCR INM approach than under NPK alone. STCR-based treatment that included STCR INM and 75% STCR dose of N + green manure had improved soil properties. It was concluded from the present experiment that fertilizer recommendations based on the Soil Test Crop Response approach combined with organic manure assist in the management of nutrients and reduce the use of excessive fertilizers, which restores soil fertility, maintains soil health and environmental quality by reducing excessive fertilizer consumption
  • Thumbnail Image
    ThesisItemOpen Access
    Experimental investigation of thermo-hydraulic performance of rotating packed bed using air-water system
    (G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2022-04) Sandeep Kumar; Murthy, D.S.
    Rotating packed bed (RPB) has a great potential for process intensification in thermal systems. However, the available literature is only focused on its mass transfer aspects and no study shows its heat transfer aspects. In rotating packed bed, the water flows outwards from the inner periphery of a rotating rotor by centrifugal action and air travels inwards from the outer periphery by imposed pressure gradient making a counter current interaction with each other. The rotation of the rotor gives control over the water distribution unlike in conventional columns where gravity is the only driving force. In present work, rotating packed bed (RPB) have been explored for process intensification in thermal systems using air-water as working fluids. The thermo-hydraulic performance of rotating packed was carried out considering the air flow rate range varying from 0.007625 kg/s to 0.020175 kg/s, water flow rate varies from 0.033 kg/s to 0.133 kg/s and rotational speed considered is 0-2000 rpm. The thermal performance parameters such as cooling range, approach, water evaporation rate, heat transfer rate, Merkel number, and effectiveness for the RBP were experimentally evaluated for the given airflow rate, water flow rate and water inlet temperature (35, 40, and 45°C) and rotational speed. The optimum result for all the thermal performance parameters was observed at 1200 rpm. At the optimum condition, the observed value of cooling range was 15 ̊C, the value of approach was 12.2 ̊C, water evaporation rate was 0.000904 kg/s, effectiveness was 0.49 and the Merkel number was 0.426. The results were found to be in agreement with CTI (Cooling Technology Institute) performance curve charts, confirming the feasibility of RPBs to be used as thermal systems.