Performance Of Single Stage Research Articles

Investigation on the Performance of Single Stage Multistring Inverter for Grid Connected Photovoltaic System

Investigation on the Performance of Single Stage Multistring Inverter for Grid Connected Photovoltaic System

Numerical model-based prediction of performance of single stage traveling wave thermo-acoustic engines

In the recent past, attraction towards the new power generation technologies and thermal energy recovery have become exponentially increasing due to the environmental and economic concerns. Thermo-acoustic generation has been identified as an attractive novel technology for low-grade energy recovery and power generation. Only moving component of the thermo-acoustic generation system is the linear alternator, which is used to convert acoustic energy into electrical energy, and hence, it leads to increase the reliability of thermo-acoustic systems with comparative to the other power generation technologies. Traveling wave thermo-acoustic generators have higher efficiencies with respective to its counterpart, standing-wave thermo-acoustic generators. Traveling wave thermo-acoustic generators are much economical and less complex as it can be operated with ambient air at atmospheric pressure conditions as the working fluid. During this study, a single stage traveling-wave​ thermo-acoustic engine was modeled and validated using available test results in the literature. The validated model was used to predict the optimum working conditions for a traveling wave thermo-acoustic engine to obtain the maximum efficiency from the engine. Results show that the increment of temperature in hot heat exchanger tends to increase the efficiency of the system.

Design and Performance of Single Stage Three Phase Solar Photo Voltaic using CTF-UPQC

An algorithm is necessary for high performance, reliable and secure control in three phase solar photovoltaic cell. Three phase single stage solar photovoltaic is designed and analysed in this paper by using control triangular function unified power quality conditioner (PV-CTFUPQC) technique. By using PV-CTFUPQC technique, the functioning of three-phase single stage solar photovoltaic can be improved. To produce fundamental output, PV-CTFUPQC maintains Root mean square (RMS) but in the proposed control RMS block is not needed. By using MATLAB/Simulink platform, three phase solar photo voltaic is designed and simulated. The proposed system function is validated on developed laboratory model. The generation of clean energy and enhancement in quality power are provided by proposed system.

Performance evaluation of attached biofilm reactors for the treatment of wastewater contaminated with aromatic hydrocarbons and phenolic compounds

The present study investigated the performance of single stage moving bed biological reactor (MBBR) and submerged aerated biological filter (SABF) for the treatment of wastewater contaminated with heterocyclic and homocyclic aromatic hydrocarbons along with phenolic compounds commonly discharged from coal and biomass gasification plants. Performance evaluation of both the bioreactors was carried out by varying hydraulic and organic loading rates (OLR). Removal efficiencies (R.E) of 90.4±0.78% and 85.8±1.96% were achieved in MBBR and SABF, respectively at HRT of 24h and OLR of 2.45kg/m3/day. Increasing the OLR to 4.77kg/m3/day resulted in the reduction of R.E of MBBR and SABF to 86±0.96% and 77.8±1.45%, respectively. MBBR showed better stability against hydraulic and organic shock loads in comparison to SABF. The effect of co-contaminants such as phenol and cresol on overall reactor performance was also investigated. The coexistence of phenol (300mg/L) and cresol (100mg/L) affected the removal of other hydrocarbons and resulted in accumulation of the metabolic intermediates. TOC R.E was 86.8% and 84.9% while reduction in toxicity was 61% and 57% in MBBR and SABF during simultaneous treatment of mixed hydrocarbons and phenolic compounds (OLR=3.43kg/m3/day, HRT=24h). Modified Stover- Kincannon model was incorporated to elucidate the substrate utilization kinetics. Characterization of attached biofilm on the carrier elements showed a significant variation in extracellular polymeric constituents with different pollutant concentrations.

Performance Comparison of QPSK Based Single and Double Stage Digital Interpolators

In this paper, the performance of single stage and double stage digital interpolators has been compared and has been showed that by using multi stage interpolation system the reliability of any communication system increases drastically. Digital signal interpolation systems can be implemented in a variety of ways. The basic interpolator for up-sampling can be a combination of an expander unit with an interpolation low-pass lter in cascade. Complicated implementations can be done by connecting multiple expander and low-pass lter pairs in cascade. This paper presents the e cient implementation of digital interpolation systems for up-sampling of single stage and double stage digital interpolators by using quadrature phase shift keying technique. Comparison is done in terms of spectrum of generated signal, envelope power, modulated signal trajectory, input and output constellation and noise performance.

Experimental investigations on single stage, two stage and three stage conventional Savonius rotor

The performance of single stage (rotor aspect ratio of 1.0), two stage Savonius rotor with rotor aspect ratios of 1.0 and 2.0 (stage aspect ratios of 0.50 and 1.0) and three stage Savonius rotor with rotor aspect ratios of 1.0 and 3.0 (stage aspect ratios of 0.33 and 1.0) are studied at different Reynolds numbers and compared at the same Reynolds number. The results show that the coefficient of power and the coefficient of torque increase with the increase in the Reynolds numbers for all the rotors tested. The coefficient of static torque is independent of the Reynolds number for all the rotors tested. The performance of two stage and three stage rotors remains the same even after increasing the stage aspect ratio and the rotor aspect ratio by a factor of two and three, respectively. For the same rotor aspect ratio of 1.0, by increasing the number of stages (stage aspect ratio decreases), the performance deteriorates in terms Cp and Ct. However, at the same stage aspect ratio of 1.0 and same Reynolds number, two and three stage rotors show the same performance in terms of coefficient of power and coefficient of torque. The variation in coefficient of static torque is lower for a three stage rotor when compared with the variation of coefficient of static torque for two stage or single stage rotor. Copyright © 2008 John Wiley & Sons, Ltd.

Optimising expansion deflection nozzles for vacuum thrust

AbstractWhile expansion deflection (ED) nozzles have traditionally been considered primarily for use as altitude compensating devices to improve the performance of single stage to orbit vehicles, they also offer the potential for enhancing high altitude propulsion systems. If intended to only operate in near vacuum conditions, the complexity of analysis and inherent risks involved in the ED concept are greatly reduced. An integrated approach to the design and performance analysis of such nozzles is presented, comprising a mixture of computational fluid dynamics, the method of characteristics, and a semi-empirical model to allow full analysis of the closed wake flow-field of an ED nozzle. While it is demonstrated that the influence of the parameters used to define the throat region is critical to the successful application of the ED nozzle, it is also shown that with careful design the weight savings possible are significant. The analysis method itself is flexible and rapid, and lends itself well to incremental improvements in accuracy as the flow under consideration becomes better understood.

Theoretical comparison of single stage and advanced absorption heat transformers operating with water/lithium bromide and water/Carrol mixtures

A thermodynamic analysis was carried out to compare the theoretical performance of single stage, two stage and double-absorption heat transformers operating with the water/lithium bromide and the water/Carrol mixtures, where Carrol is a mixture of lithium bromide and ethylene glycol [(CH2OH)2] in the ratio 1:4·5 by weight. A mathematical model to predict the theoretical performance of single stage and the advanced heat transformers is also described. Coefficients of performance and gross temperature lifts are compared for the different heat transformers and plotted against the main temperatures of the system for both mixtures. The water/Carrol mixture showed in general to have a better performance than the water/lithium bromide mixture. © 1998 John Wiley & Sons, Ltd.

Theoretical comparison of single stage and advanced absorption heat transformers operating with water/lithium bromide and water/Carrol mixtures

A thermodynamic analysis was carried out to compare the theoretical performance of single stage, two stage and double-absorption heat transformers operating with the water/lithium bromide and the water/Carrol mixtures, where Carrol is a mixture of lithium bromide and ethylene glycol [(CH2OH)2] in the ratio 1:4·5 by weight. A mathematical model to predict the theoretical performance of single stage and the advanced heat transformers is also described. Coefficients of performance and gross temperature lifts are compared for the different heat transformers and plotted against the main temperatures of the system for both mixtures. The water/Carrol mixture showed in general to have a better performance than the water/lithium bromide mixture. © 1998 John Wiley & Sons, Ltd.