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Abstract In this article, a novel analytical approach (named as zero bus load flow (ZBLF)) is proposed for DG placement to the distribution network under the scenario of known power injection from the utility/substation. The study is carried out for deferent load levels and for two different distribution networks (viz. 33- and 69-bus distribution networks). In this work, biomass (working at the power factor same as that of the load power factor) is considered as the DG source. From this study, it may be noticed that, by placing the DG at the selected bus, the active power loss of the network may be reduced even when the power supply from the utility grid is zero. In this paper, a combined approach of ZBLF and symbiotic organism search (SOS) has been proposed for the placement of multiple numbers of DGs for the scenario when the power supply from the utility/substation is known. Both the technical as well as the economic aspects of the DG placement for both the distribution networks are studied and presented in this research paper. DG placement using the proposed method also founds to be economical to the utility.

Abstract The roles of integrated decentralized energy production and distribution systems are considered. System analysis is needed to construct scenarios for long-term energy development in selected rural clusters. Here, we define an energy plan for the Fatehpur village cluster to the year 2001 using a generally applicable methodology.

Abstract The present work reports studies on the fluidization of mixtures of biomass and sands. The biomass materials used are rice husk, sawdust and groundnut shell powder, and the sands employed are of two different densities and particle sizes. Experiments are carried out in a 5 cm ID fluidized bed column to determine the minimum fluidization velocities. The percentage of biomass materials in the mixtures studied are 2, 5, 10 and 15% by weight. Equations are developed for predicting the U mf values of these mixtures. The equations are also tested for their validity against the data in current literature on U mf values of mixtures of biomass and sands and also mixtures of particles of different sizes only. It is found that the proposed equations quite satisfactorily predict the U mf values for mixtures of different particle densities and sizes.

Abstract We have investigated a fin-type air heater, both experimentally and theoretically. In the experimental set-up, the fins are integrated with the upper plate of the conventional duct-type air heater with single glazing. The experiments were performed on two clear days for two different mass-flow rates. A transient model is then developed to study the performance of the finned air heater and, by adjusting heat-transfer coefficients, the theoretical data are fitted to the experimental results. Agreement between theoretical predictions and experimental values is found to be good. We have used the resulting values of the heat-transfer coefficient to predict the performance of the system when the fins are placed in the lower metallic plate or in both the upper and lower plates. The dependence of efficiency on fin density has been studied.

Abstract The temperature dependence of the overall heat-loss coefficient for flat-plate collectors has been studied by using stagnation measurements made with different configurations, viz., tilt 45 °s with single and double glazing and tilt 0 ° with single glazing. Comparisons have been made with theoretical results. The agreement between the calculated and experimental results is found to be quite good.

We apply an analytical expression to the plants and enclosed air in a greenhouse for various design parameters and a given climatic condition. A numerical method has been used to validate an analytical expression for the plant temperature. Our analysis is based on energy-balance equations for different components of the greenhouse. Numerical computations have been carried out for a typical summer day in Delhi. The effects of parameters such as the rate and duration of ventilation, movable insulation, etc. have been studied. Our model may be used to standardize a greenhouse for any climatic conditions.

Abstract Highly intermittent power, generated by wind energy in an isolated hybrid power system (IHPS), results in severe frequency and power fluctuation. The aim of this paper is to carry out a comparative study of scaling factor (SF) based fuzzy logic controller (FLC) (SF-FLC), SF-FLC with proportional-integral (PI) (SF-FLC-PI) controller, SF-FLC with proportional-derivative (PD) (SF-FLC-PD) controller and SF-FLC with proportional-integral-derivative (PID) (SF-FLC-PID) controller for deviation in frequency and power of an IHPS model. The undertaken model of IHPS for this study embraces a diesel engine generator, a wind turbine generator and an energy storage device (for instance, capacitive energy storage). Optimal tuning of the different tunable parameters considered for suppressing the deviation in frequency and power of IHPS model owing to alteration in load demand has been carried out by quasi-oppositional harmony search (QOHS) algorithm. The obtained results demonstrate minimum deviation in frequency and power may be realized by practicing the proposed SF-FLC-PID controller for the considered IHPS model. Robustness and non-linearity investigation have been also executed for the proposed SF-FLC-PID controller based configuration of the studied IHPS model. It is revealed that the proposed SF-FLC-PID controller is very much robust in nature and takes care of non-linearity very well while QOHS algorithm is adopted.

Abstract The increasing demand for cryogenic fluids is acquiring the research attention to develop efficient machines to produce cryogenic temperature such as turboexpander based system. The expansion turbine and nozzle of a turboexpander are the critical components of such systems, and its performance has a significant effect on the overall efficiency of the system. In this paper, the effective design methodology of a radial inflow turbine by considering different loss models is presented. The methodology consists of one-dimensional modeling to describe the geometrical parameters of the nozzle and turbine. The optimal range of important non-dimensional variables such as blade speed, pressure ratio, ratio of hub and shroud radius to turbine inlet radius are predicted using artificial intelligence techniques for better performance of the turbine. This approach improves the turbine efficiency and power output by 4 % and 18.9 % respectively as compared to the existing model. The three-dimensional numerical investigation is carried out to visualize the fluid flow and thermal characteristics of the designed turbine and nozzle. The study also focuses on to identify the flow separation zone, tip leakage flow, vortex formation, secondary losses and its reasons at different spanwise locations of the turbine. Additionally, Sobol sensitivity analysis method is used to distinguish the significance of different assumed constants on the total losses and non-dimensional design variables on total-to-static efficiency. Finally, the numerical results are validated with experimental data of a case study. The study highlights the importance of the design methodology, the prediction capability of artificial intelligence method, Sobol sensitivity analysis, the experimental techniques and benchmarking model for numerical analysis at different cryogenic temperature.

Abstract Methane generation from waste landfills is one of the biggest contributors to global warming. The purpose of this study was twofold: (i) to investigate methane concentration from Municipal Solid Waste (MSW) at three landfills in Dhanbad city, India and (ii) to evaluate the amount of energy that could be recovered based on the MSW characteristics if it were to be incinerated. The waste samples were collected and analysed for composition, energy content, and methane concentration. Results from MSW characterisation revealed that the main component of Dhanbad MSW is organic waste, which made up to 75% of the waste by weight. Methane concentration and moisture content from Railway station (site 1) and Memco-more (site 2 and site 3) measured as 140.53, 18.18 and 20.28 ppm methane/g waste and 25.49, 3.40 and 2.96% dry weight respectively. The calorific value for the waste samples ranged between 10.7 and 13.0 MJ/kg. These findings confirm that the methane generated at the sites can be used for energy recovery. Additionally, the energy content of the MSW suggests that it is a suitable feedstock that can be utilized for electricity generation through combustion.