Study on the Operational Window of a Swirl Stabilized Syngas Burner Under Atmospheric and High Pressure Conditions

Providing better fuel flexibility for future gas turbine generations is a challenge as the fuel range is expected to become significantly wider (natural gas, syngas, etc.). The technical problem is to reach a wide operational window, regarding both operational safety and low emissions. In a previous paper, an approach to meet these requirements has already been presented. However, in this previous study it was difficult to exactly quantify the improvement in operational safety due to the fact that the flashback phenomena observed were not fully understood. The present continuative paper is focused on a thorough investigation of operational safety also involving the influence of pressure on flashback and the emissions of the proposed burner concept. To gain better insight into the character of the propagation and to visualize the path of the flame during its upstream motion, tests were done on an atmospheric combustion test rig providing almost complete optical access to the mixing section as well as the flame tube. OH* chemiluminescence, HS-Mie scattering and ionization detectors were applied and undiluted H2 was used as fuel for the detailed analysis. To elaborate on the influence of pressure on the stability behavior, additional tests were conducted on a pressurized test rig using a downscaled burner. OH* chemiluminescence, flashback and lean blow out measurements were conducted in this campaign, using CH4, CH4/H2 mixtures and pure H2. The conducted experiments delivered the assets and drawbacks of the fuel injection strategy, where high axial fuel momentum was used to tune the flow field to achieve better flashback resistance.

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Study on the Operational Window of a Swirl Stabilized Syngas Burner Under Atmospheric and High Pressure Conditions

Volume 2: Combustion, Fuels and Emissions, Parts A and B ◽

10.1115/gt2011-45125 ◽

2011 ◽

Cited By ~ 1

Author(s):

C. Mayer ◽

J. Sangl ◽

T. Sattelmayer ◽

T. Lachaux ◽

S. Bernero

Keyword(s):

Fuel Injection ◽

Technical Problem ◽

Mie Scattering ◽

Test Rig ◽

Stability Behavior ◽

Operational Window ◽

Fuel Flexibility ◽

Operational Safety ◽

The Stability ◽

Ionization Detectors

Providing better fuel flexibility for future gas turbine generations is a challenge as the fuel range is expected to become significantly wider (natural gas, syngas, etc.). The technical problem is to reach a wide operational window, regarding both operational safety and low emissions. In a previous paper an approach to meet these requirements has already been presented. However, in this previous study it was difficult to exactly quantify the improvement in operational safety due to the fact that the flashback phenomena observed were not fully understood. The present continuative paper is focused on a thorough investigation of operational safety also involving the influence of pressure on flashback and the emissions of the proposed burner concept. To gain better insight in the character of the propagation and to visualize the path of the flame during its upstream motion, tests were done on an atmospheric combustion test rig providing almost complete optical access to the mixing section as well as the flame tube. OH* chemiliuminescence, HS-Mie scattering and ionization detectors were applied and undiluted H2 was used as fuel for the detailed analysis. To elaborate the influence of pressure on the stability behavior additional tests were done on a pressurized test rig using a downscaled burner. OH* chemiluminescence, flashback and lean blow out measurements were conducted in this campaign, using CH4, CH4/H2 mixtures and pure H2. The conducted experiments delivered the assets and drawbacks of the fuel injection strategy, where high axial fuel momentum was used to tune the flow field to achieve better flashback resistance.

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Industrial Trent Combustor — Combustion Noise Characteristics

Volume 2: Coal, Biomass and Alternative Fuels; Combustion and Fuels; Oil and Gas Applications; Cycle Innovations ◽

10.1115/99-gt-009 ◽

1999 ◽

Cited By ~ 2

Author(s):

Thomas Scarinci ◽

John L. Halpin

Keyword(s):

Fuel Injection ◽

Power Level ◽

Technical Problem ◽

Combustion Noise ◽

Ambient Conditions ◽

Noise Mapping ◽

Noise Characteristics ◽

Lean Premixed ◽

In Series ◽

Three Stages

Thermoacoustic resonance is a difficult technical problem that is experienced by almost all lean-premixed combustors. The Industrial Trent combustor is a novel dry-low-emissions (DLE) combustor design, which incorporates three stages of lean premixed fuel injection in series. The three stages in series allow independent control of two stages — the third stage receives the balance of fuel to maintain the desired power level — at all power conditions. Thus, primary zone and secondary zone temperatures can be independently controlled. This paper examines how the flexibility offered by a 3-stage lean premixed combustion system permits the implementation of a successful combustion noise avoidance strategy at all power conditions and at all ambient conditions. This is because at a given engine condition (power level and day temperature) a characteristic “noise map” can be generated on the engine, independently of the engine running condition. The variable distribution of heat release along the length of the combustor provides an effective mechanism to control the amplitude of longitudinal resonance modes of the combustor. This approach has allowed the Industrial Trent combustion engineers to thoroughly “map out” all longitudinal combustor acoustic modes and design a fuel schedule that can navigate around regions of combustor thermoacoustic resonance. Noise mapping results are presented in detail, together with the development of noise prediction methods (frequency and amplitude) that have allowed the noise characteristics of the engine to be established over the entire operating envelope of the engine.

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Bioinspired organometallic chemistry

Pure and Applied Chemistry ◽

10.1351/pac200274010115 ◽

2002 ◽

Vol 74 (1) ◽

pp. 115-122 ◽

Cited By ~ 24

Author(s):

Lanny S. Liebeskind ◽

Jiri Srogl ◽

Cecile Savarin ◽

Concepcion Polanco

Keyword(s):

Organometallic Chemistry ◽

Refractory Metal ◽

Redox Active ◽

The Stability ◽

New Procedures ◽

Sulfur Containing ◽

Insight Into

Given the stability of the bond between a mercaptide ligand and various redox-active metals, it is of interest that Nature has evolved significant metalloenzymatic processes that involve key interactions of sulfur-containing functionalities with metals such as Ni, Co, Cu, and Fe. From a chemical perspective, it is striking that these metals can function as robust biocatalysts in vivo, even though they are often "poisoned" as catalysts in vitro through formation of refractory metal thiolates. Insight into the nature of this chemical discrepancy is under study in order to open new procedures in synthetic organic and organometallic chemistry.

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On the Trigonometric Descriptions of Colors

Applied Physics Research ◽

10.5539/apr.v8n3p5 ◽

2016 ◽

Vol 8 (3) ◽

pp. 5

Author(s):

Jirí Stavek

Keyword(s):

Experimental Data ◽

Transverse Energy ◽

Gravitational Constant ◽

Isaac Newton ◽

Type Ia ◽

New Interpretation ◽

The Stability ◽

Mass Evaporation ◽

Supernovae Type Ia ◽

Insight Into

An attempt is presented for the description of the spectral colors using the standard trigonometric tools in order to extract more information about photons. We have arranged the spectral colors on an arc of the circle with the radius R = 1 and the central angle θ = π/3 when we have defined cos (θ) = λ380/λ760 = 0.5. Several trigonometric operations were applied in order to find the gravity centers for the scotopic, photopic, and mesopic visions. The concept of the center of gravity of colors introduced Isaac Newton. We have postulated properties of the long-lived photons with the new interpretation of the Hubble (Zwicky-Nernst) constant H0 = 2.748… * 10-18 kg kg-1 s-1, the specific mass evaporation rate (SMER) of gravitons from the source mass. The stability of international prototypes of kilogram has been regularly checked. We predict that those standard kilograms due to the evaporation of gravitons lost 8.67 μg kg-1 century-1. The energy of long-lived photons was trigonometrically decomposed into three parts that could be experimentally tested: longitudinal energy, transverse energy and energy of evaporated gravitons. We tested the properties of the long-lived photons with the experimental data published for the best available standard candles: supernovae Type Ia. There was found a surprising match of those experimental data with the model of the long-lived photons. Finally, we have proposed a possible decomposition of the big G (Newtonian gravitational constant) and the small kappa κ (Einsteinian gravitational constant) in order to get a new insight into the mysterious gravitational force and/or the curvature concept.

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Influence of additives on suspension structure

Advanced technologies ◽

10.5937/savteh2101037s ◽

2021 ◽

Vol 10 (1) ◽

pp. 37-40

Author(s):

Vesna Savić ◽

Milica Martinović ◽

Ivana Nešić ◽

Jelena Živković ◽

Ivana Gajić

Keyword(s):

Zinc Oxide ◽

The Other ◽

Stability Tests ◽

Polysorbate 20 ◽

The Stability ◽

Carbomer Gel ◽

Suspension Structure ◽

Insight Into ◽

Study Offer ◽

Measured Hardness

The aim of this study was to compare the stability and texture of three zinc oxide suspensions with different additives. Suspension 1 was made as official magistral formulation Suspensio album 7.5% from Formulae magistrales 2008. Suspension 2 was prepared when 1% carbomer gel was added to suspension 1 and suspension 3 was prepared when polysorbate 20 was added to suspension 2. After stability tests, texture analysis was performed on all suspensions. Following parameters were measured: hardness cycle 1, hardness cycle 2, cohesiveness, adhesiveness, resilience and springiness. The study showed that suspension 3 had the lowest value of hardness, and therefore the best spreadability. Also, suspension 3 was the least sticky of all three, since it was characterized with the lowest adhesiveness. Further, suspension 3 was the most cohesive and is predicted to withstand the stress during packing and use longer than others. On the other hand, the highest values of resilience and springiness were detected for suspension 1, while the lowest was related to suspension 2. Therefore, the best textural characteristics were assigned to suspension 3. This result is in accordance with the results of performed stability tests. The results of our study offer insight into potential improvements of the current magistral formulation Suspensio album 7.5%.

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Een geconstrueerd denken

Handelingen - Koninklijke Zuid-Nederlandse Maatschappij voor Taal- en Letterkunde en Geschiedenis ◽

10.21825/kzm.v61i0.17431 ◽

1970 ◽

Vol 61 ◽

pp. 269-292

Author(s):

Rajesh Heynickx

Keyword(s):

Main Argument ◽

Cultural Project ◽

The Stability ◽

Insight Into ◽

The Way

In this article it is demonstrated that an analysis of how building metaphorswere used in the Flemish Catholic discourse of the interwar years can offermore insight into the way a community of believers tries to establish a culturalcohesiveness. The main argument is that in a period of deep transformations,building metaphors could become "instruments" for Catholics whowanted to defend and promote a traditional dimension of their religion.Building metaphors allowed Catholics to stress the stability of their own ideology(the fundaments) and to formulate their own cultural project (buildingplan). By analysing such strategic use of building metaphors in artistic andphilosophical discourses, it can become possible to shed more light on the roleneo-thomism, a main philosophical current in interwar Flanders, played inartistic debates and more specific in discussions on the modernisation of religiousart.

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Fuel Injection Control for a Valve Array in a Shockless Explosion Combustor

Volume 6: Ceramics; Controls, Diagnostics, and Instrumentation; Education; Manufacturing Materials and Metallurgy ◽

10.1115/gt2018-75295 ◽

2018 ◽

Cited By ~ 1

Author(s):

Jan-Simon Schäpel ◽

Rudibert King ◽

Fatma Yücel ◽

Fabian Völzke ◽

Christian Oliver Paschereit ◽

...

Keyword(s):

Fuel Injection ◽

Combustion Process ◽

Firing Frequency ◽

Mixed Integer ◽

Test Rig ◽

Proportional Valve ◽

Control Approach ◽

Fuel Stratification ◽

Auto Ignition ◽

Filling Time

Approximate constant volume combustion (aCVC) is a promising way to optimize the combustion process in a gas turbine, which would exceed the gain in efficiency resulting from optimizing other components significantly. This work deals with a recently proposed approach: shockless explosion combustion (SEC). Compared to already known concepts, such as pulsed detonation combustion (PDC), it overcomes several disadvantages, e.g., sharp pressure transitions and entropy generation due to shock waves. For an SEC, accurate fuel stratification is required to achieve a quasi-homogeneous auto-ignition. In an atmospheric test rig quasi-homogeneous ignitions were achieved previously in non-resonant operation. To achieve a resonant operation, which goes along with a higher firing frequency, lower ignition and injection times are required. For this purpose, an array of solenoid valves was designed to allow for highly dynamic operation within short filling time spans. Using a novel mixed-integer control approach, these solenoid valves were actuated such that a desired fuel profile was generated. In this paper, the mentioned test rig was used for non-reacting fuel measurements to compare the quality of the axial fuel stratification achieved by using the valve array with the one achieved by using a slower proportional valve. In the experimental investigation the actuation with the valve array proved to adjust the required fuel stratification with the same quality as the actuation with the proportional valve, which was already successfully applied to the reactive set-up. Hence, the mixed-integer controlled valve array is considered a useful concept for upcoming resonant reactive SEC investigations.

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Insight into the stability of protein in confined environment through analyzing the structure of water by temperature-dependent near-infrared spectroscopy

Spectrochimica Acta Part A Molecular and Biomolecular Spectroscopy ◽

10.1016/j.saa.2021.120581 ◽

2021 ◽

pp. 120581

Author(s):

Shiying Wang ◽

Mian Wang ◽

Li Han ◽

Yan Sun ◽

Wensheng Cai ◽

...

Keyword(s):

Infrared Spectroscopy ◽

Near Infrared Spectroscopy ◽

Near Infrared ◽

Temperature Dependent ◽

Structure Of Water ◽

The Stability ◽

Confined Environment ◽

Insight Into

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Impacts of duct inner diameter and standoff distance on macroscopic spray characteristics of ducted fuel injection under non-vaporizing conditions

International Journal of Engine Research ◽

10.1177/1468087420914714 ◽

2020 ◽

pp. 146808742091471

Author(s):

Feng Li ◽

Chia-fon Lee ◽

Ziman Wang ◽

Yiqiang Pei ◽

Guoxiang Lu

Keyword(s):

Large Scale ◽

Fuel Injection ◽

Soot Formation ◽

Cone Angle ◽

Mie Scattering ◽

Standoff Distance ◽

Spray Characteristics ◽

Spray Cone Angle ◽

Spray Cone ◽

Inner Diameter

Ducted fuel injection spray is a new technology for reducing soot formation in heavy-duty diesel engines. In this work, the ducted fuel injection spray characteristics with different duct inner diameters and different standoff distances were investigated and compared with free spray. Duct inner diameter ranged from 1.5 to 4 mm, and standoff distance varied between 0.9 and 4.9 mm. Mie-scattering optical technique was used to characterize spray characteristics under various injection pressures in a constant-volume spray chamber. Ambient gas pressure of up to 6 MPa when spraying. The results showed that ducted fuel injection spray with smaller duct has better spray diffusion compared to those of ducted fuel injection sprays with larger ducts and free spray from the perspectives of spray tip penetration, spray cone angle and spray area. Increasing standoff distance could increase spray velocity. Ducted fuel injection spray with smaller duct formed a mushroom-shaped head and large-scale vortex flow close to the duct outlet. All the advantages of ducted fuel injection spray with smaller duct are interpreted as evidence of improving fuel–gas mixing quality significantly.

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