Further Development of an Advanced Low-NOx Combustion System and its Potential Application to Coal-Fired Utility Boilers

1980 ◽  
Vol 102 (3) ◽  
pp. 684-691 ◽  
Author(s):  
T. M. Sommer ◽  
S. A. Johnson ◽  
G. D. Lindstrom
Keyword(s):  
Kinetic Mechanism ◽  
Design Parameters ◽  
Small Scale ◽  
Prototype System ◽  
Combustion System ◽  
Design Considerations ◽  
Utility Boilers ◽  
Low Nox Combustion ◽  
Further Development ◽  
Initial Results

The Babcock & Wilcox Company (B&W), under contract with the Electric Power Research Institute (EPRI), has designed and tested an advanced staged combustion system on a four million Btu/hr (4.2-million kJ/hr) scale. Results of these tests showed the potential to limit the emission of nitrogen oxides from coal-fired boilers to 100–150 ppm and identified a new kinetic mechanism for NO destruction. Subsequently, the correlations and initial design parameters derived from the small-scale tests were applied to a conceptual commercial system to ensure that this concept was indeed commercially feasible. These design considerations and the favored preliminary arrangement of a low-NOx combustion system will be discussed herein. Before commercializing this concept, however, further research is necessary. Testing on a nominal 50-million Btu/hr (53-million kJ/hr) prototype system is now in progress. Initial results indicate that NOx emission correlations and design parameters will need only slight revisions before the concept is ready for a field demonstration.

scholarly journals Dry Low NOx Combustion System for Utility Gas Turbine

1983 ◽  
Author(s):  
R. M. Washam
Keyword(s):  
Carbon Monoxide ◽  
Gas Turbine ◽  
Performance Standards ◽  
Nox Emissions ◽  
Combustion System ◽  
Load Range ◽  
Stage Combustion ◽  
Low Nox Combustion ◽  
Multimode Operation ◽  
Further Development

A Dry Low NOx combustion system has been developed for a 80 MW gas turbine operating on natural gas and on distillate oil. The system, employing two-stage combustion and multimode operation, meets the New Source Performance Standards (NSPS) for NOx emissions across much of the load range for both fuels. Mid-load smoke, NOx, and carbon monoxide emissions on distillate oil require further development. This paper outlines the emissions performance of the system for Dry Low NOx applications, specifically in terms of NSPS NOx requirements. Machine data, in addition to test stand data, support the conclusions.

Treatment of Rural Domestic Sewage by Solar Ozonic Ecological Sewage Treatment Plant

2014 ◽  
Vol 955-959 ◽  
pp. 3393-3399 ◽  
Author(s):  
Wei Zheng ◽  
Yan Ming Yang ◽  
Yun Long Li ◽  
Jian Qiu Zheng
Keyword(s):  
Municipal Wastewater ◽  
Operating Cost ◽  
Sewage Treatment ◽  
Sewage Treatment Plant ◽  
Treatment Plant ◽  
Domestic Sewage ◽  
Design Parameters ◽  
Small Scale ◽  
Municipal Wastewater Treatment ◽  
Average Percentage

The process technique and design parameters of project of Solar Ozonic Ecological Sewage Treatment Plant (short for SOESTP) which consists of anaerobic reactor, horizontal subsurface flow (HSSF) constructed wetlands(CWs) and the combination of solar power and ozone disinfection are described, the paper further examines the removal efficiency for treating rural domestic sewage, running expense and recycling ability of product water. The results show that the average percentage removal values of CODcr，BOD5，SS，TN，NH3-N，TP range from 95.6% to 98.0%, 96.0% to 98.7%, 93.1% to 96.1%, 97.0% to 98.9%, 96.9% to 99.5%, 98.2% to 99.6%, respectively, the reduction of fecal coliform (FC) reaches 99.9%, the effluent quality meets the first level A criteria specified in Discharge Standard of Pollutants for Municipal Wastewater Treatment Plant（GB18918-2002）. The running cost of SOESTP is 0.063yuan/ m3, saves much more than traditional sewage treatment, and the ozone water obtained from the reservoir will be an ideal choice for disinfection .The system has characteristics of easy manipulation, low operating cost, achieving advanced water, energy conservation and environment protection, is thought to be very suitable for use as the promotion of rural small - scale sewage treatment.

Feasibility Study of Designing a Three Legged Walking Robot: Tribot

1991 ◽  
Author(s):  
Yueh-Jaw Lin ◽  
Aaron Tegland
Keyword(s):  
Feasibility Study ◽  
Legged Robots ◽  
Walking Robots ◽  
Design Parameters ◽  
Optimized Design ◽  
Motion Simulation ◽  
Walking Robot ◽  
Design Considerations ◽  
Simulation Based ◽  
Weight Distributions

Abstract In recent years, walking robot research has become an important robotic research topic because walking robots possess mobility, as oppose to stationary robots. However, current walking robot research has only concentrated on even numbered legged robots. Walking robots with odd numbered legs are still lack of attention. This paper presents the study on an odd numbered legged (three-legged) walking robot — Tribot. The feasibility of three-legged walking is first investigated using computer simulation based on a scaled down tribot model. The computer display of motion simulation shows that a walking robot with three legs is feasible with a periodic gait. During the course of the feasibility study, the general design of the three-legged robot is also analyzed for various weights, weight distributions, and link lengths. In addition, the optimized design parameters and limitations are found for certain knee arrangements. These design considerations and feasibility study using computer display can serve as a general guideline for designing odd numbered legged robots.

Optimizing Perimeter Surveillance Drones to enhance the security system of unmanned aerial vehicles

2021 ◽  
Vol 2 (2) ◽  
pp. 105-115
Author(s):  
Mahmod Al-Bkree
Keyword(s):  
Unmanned Aerial Vehicles ◽  
Security System ◽  
Small Scale ◽  
Security Systems ◽  
Ongoing Research ◽  
Aerial Vehicles ◽  
Aerial Vehicle ◽  
Initial Results

This work is to optimize perimeter surveillance and explore the distribution of ground bases for unmanned aerial vehicles along the Jordanian border and optimize the set of technologies for each aerial vehicle. This model is part of ongoing research on perimeter security systems based on unmanned aerial vehicles. The suggested models give an initial insight about selecting technologies carried by unmanned aerial vehicles based on their priority; it runs for a small scale system that can be expanded, the initial results show the need for at least four ground bases along the length of the border, and a selected set of various technologies for each vehicle.

Mechanisms performance and pressure dependence of hydrogen/air burner-stabilized flames

2018 ◽  
Vol 13 (6) ◽  
pp. 51
Author(s):  
V. Bykov ◽  
V.V. Gubernov ◽  
U. Maas
Keyword(s):  
Chemical Kinetics ◽  
Critical Mass ◽  
Molecular Transport ◽  
Kinetic Mechanism ◽  
Elevated Pressure ◽  
Porous Plug ◽  
Combustion System ◽  
Hydrocarbon Combustion ◽  
Chemical Reaction Mechanisms ◽  
Combustion Processes

The kinetic mechanism of hydrogen combustion is the most investigated combustion system. This is due to extreme importance of the mechanism for combustion processes, i.e. it is present as a sub-mechanism in all mechanisms for hydrocarbon combustion systems. Therefore, detailed aspects of hydrogen flames are still under active investigations, e.g. under elevated pressure, under conditions of different heat losses intensities and local equivalence ratios etc. For this purpose, the burner stabilized flame configuration is an efficient tool to study different aspects of chemical kinetics by varying the stand-off distance, pressure, temperature of the burner and mixture compositions. In the present work, a flat porous plug burner flame configuration is revisited. A hydrogen/air combustion system is considered with detailed molecular transport including thermo-diffusion and with 8 different chemical reaction mechanisms. Detailed numerical investigations are performed to single out the role of chemical kinetics on the loss of stability and on the dynamics of the flame oscillations. As a main outcome, it was found/demonstrated that the results of critical values, e.g. critical mass flow rate, weighted frequency of oscillations and blow-off velocity, with increasing the pressure scatter almost randomly. Thus, these parameters can be considered as independent and can be used to improve and to validate the mechanisms of chemical kinetics for the unsteady dynamics.

scholarly journals Students learning with interactive virtual math: an exploratory study in the classroom

2017 ◽  
Vol 1 (1) ◽  
pp. 80 ◽  
Author(s):  
Sônia Palha
Keyword(s):  
Secondary School ◽  
Secondary School Students ◽  
Tertiary Education ◽  
Learning Experience ◽  
Small Scale ◽  
School Students ◽  
Dynamic Events ◽  
The Subject ◽  
Scale Experiment ◽  
Further Development

Interactive Virtual Math (IVM) is a visualization tool to support secondary school students’ learning of graphs by dynamic events. In the prototype version students construct a graph and try to improve it themselves and with the feedback of the tool. In a small-scale experiment, which involved four classes at secondary and tertiary education and their mathematics teachers we investigated how the students used the tool in the classroom. In this study we focus on the students learning experience and the results are expected to provide knowledge and directions for further development of the tool. The corpus data consists of self-reported questionnaires and lessons observations. One main finding is that students, at different school levels, find the tool useful to construct or improve graphical representations and it can help to get a better understanding of the subject. The tool features that helped students most were the self-construction of the graphs and to get feedback about their own graph at the end. Other findings are that the students can work independently with the tool and we know more about the tool features that are attractive or need to be improved.

scholarly journals An Interdisciplinary Approach to the Sustainability of a Gravity-Fed Water System in the Peruvian Andes

2019 ◽  
Vol 14 (3) ◽  
pp. 49-60
Author(s):  
Riley Orabona Wagner ◽  
Sydney Hsu ◽  
John Nicholas Kick ◽  
Sofia Bisogno ◽  
Camille Heubner ◽  
...  
Keyword(s):  
Water System ◽  
Interdisciplinary Approach ◽  
Design Parameters ◽  
Small Scale ◽  
Development Projects ◽  
Peruvian Andes ◽  
Princeton University ◽  
Future Success ◽  
Local Partnerships ◽  
Engineers Without Borders

This paper analyzes the methods utilized by the Princeton University Chapter of Engineers Without Borders to ensure the sustainability of a gravity-fed water system in rural northwestern Peru. While similar small scale development projects consider sustainability in their design process, some do not recognize the importance of an interdisciplinary approach to sustainability. This team, however, is inherently interdisciplinary in nature due to its unique subteam structure, which subsequently affects its approach to sustainability. By examining the technical, social, and financial considerations of the project conducted by the Princeton University Chapter of Engineers Without Borders, this paper argues for a three-pronged approach to sustainability. As can be seen through thoughtful design parameters, strong local partnerships, and strategic financial mechanisms, the project displays promise of future success with regards to sustainability. The main objective of the Princeton Chapter of Engineers Without Borders in this partnership is to ensure that the community has the knowledge, tools, and resources necessary to maintain the water system in a self-sufficient manner at the completion of the chapter’s involvement.

Small Scale Supercritical CO2 Radial Inflow Turbine Meanline Design Considerations

2018 ◽  
Author(s):  
Tina Unglaube ◽  
Hsiao-Wei D. Chiang
Keyword(s):  
High Velocity ◽  
Gas Turbines ◽  
Velocity Ratio ◽  
Maximum Efficiency ◽  
Design Parameters ◽  
Working Fluid ◽  
Small Scale ◽  
Optimum Velocity ◽  
Set Up ◽  
Very High

In recent years closed loop supercritical carbon dioxide Brayton cycles have drawn the attention of many researchers as they are characterized by a higher theoretic efficiency and smaller turbomachinery size compared to the conventional steam Rankine cycle for power generation. Currently, first prototypes of this emerging technology are under development and thus small scale sCO2 turbomachinery needs to be developed. However, the design of sCO2 turbines faces several new challenges, such as the very high rotational speed and the high power density. Thus, the eligibility of well-established radial inflow gas turbine design principles has to be reviewed regarding their suitability for sCO2 turbines. Therefore, this work reviews different suggestion for optimum velocity ratios for gas turbines and aims to re-establish it for sCO2 turbines. A mean line design procedure is developed to obtain the geometric dimensions for small scale sCO2 radial inflow turbines. By varying the specific speed and the velocity ratio, different turbine configurations are set up. They are compared numerically by means of CFD analysis to conclude on optimum design parameters with regard to maximum total-to-static efficiency. Six sets of simulations with different specific speeds between 0.15 and 0.52 are set up. Higher specific speeds could not be analyzed, as they require very high rotational speeds (more than 140k RPM) for small scale sCO2 turbines (up to 150kWe). For each set of simulations, the velocity ratio that effectuates maximum efficiency is identified and compared to the optimum parameters recommended for radial inflow turbines using subcritical air as the working fluid. It is found that the values for optimum velocity ratios suggested by Rohlik (1968) are rather far away from the optimum values indicated by the conducted simulations. However, the optimum values suggested by Aungier (2005), although also established for subcritical gas turbines, show an approximate agreement with the simulation results for sCO2 turbines. Though, this agreement should be studied for a wider range of specific speeds and a finer resolution of velocity ratios. Furthermore, for high specific speeds in combination with high velocity ratios, the pressure drop of the designed turbines is too high, so that the outlet pressure is beyond the critical point. For low specific speeds in combination with low velocity ratios, the power output of the designed turbines becomes very small. Geometrically, turbines with low specific speeds and high velocity ratios are characterized by very small blade heights, turbines with high specific speeds and small velocity ratios by very small diameters.

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