scholarly journals Temperature Profile Assessment of Sub-Bituminous Coal by Using a Single Burner Combustion Test Facility

2020 ◽  
Vol 78 (1) ◽  
pp. 1-10
Author(s):  
Muhamad Shazarizul Haziq Mohd Samsuri ◽  
Hasril Hasini ◽  
Noor Akma Watie Mohd Noor ◽  
Meor Mohd Faisal Meor Zulkifli
Keyword(s):  
Temperature Profile ◽  
Gas Flow ◽  
Test Facility ◽  
Gas Temperature ◽  
Fixed Carbon ◽  
Boiler Furnace ◽  
Combustion Gas ◽  
Standard Design ◽  
Temperature Measure ◽  
Limiting Value

This paper presents a thermogravimetric analysis and combustion test for different coals used in a coal-fired power plant in Malaysia. The main objective is to investigate the suitability of adopting a newly-introduced sub-bituminuous coal in an existing boiler furnace commonly firing standard design coals. In order to ensure that the new coal will not give an adverse effect to the boiler, detail analytical and thermal performance of the new coal is investigated, together with design and other limiting coals. The combustion test was performed in a scaled down, 150kW, single swirl burner combustion test facility available in TNB Research Sdn. Bhd. In the study, combustion gas temperature at different sectors downstream of burner region is measured to determine the peak temperature for all tested coals. Based on the investigation, it was noted that coal with the highest fixed carbon content gives the highest temperature measure at all sectors. Similarly, coal with the lowest fixed carbon gives the lowest temperature. The temperature profile for the newly tested coal was found to be comparable to the design and limiting value coals. Even though it was observed that the temperature given by the new coal is the highest slightly downstream of the burner, the temperature was observed to be decreases as combustion gas flow downstream of the combustor rig. Based on the observation it can be said that the new coal is suitable to be used by the existing boiler furnace.

Exposure Test Results of Lu2Si2O7 in Combustion Gas Flow at High Temperature and High Speed

2004 ◽  
Author(s):  
Isao Yuri ◽  
Tohru Hisamatsu ◽  
Shunkichi Ueno ◽  
Tatsuki Ohji
Keyword(s):  
Weight Loss ◽  
Water Vapor ◽  
Partial Pressure ◽  
Gas Flow ◽  
Loss Rate ◽  
Gas Temperature ◽  
Weight Loss Rate ◽  
Combustion Gas ◽  
Vapor Partial Pressure ◽  
Water Vapor Partial Pressure

In order to understand recession behavior and the amount of recession of Lu2Si2O7 in the combustion gas flow, sintered Lu2Si2O7 specimens were manufactured by hot pressing and exposed under various combustion gas flow conditions (T = 1300–1500 °C, P = 0.3 MPa, V = 150 m/s, PH2O = 27–69 kPa, t = 10h). After the exposure tests, etch pits, which are assumed to form due to volatilization of SiO2 in the grain boundary phase, were observed at the surface of specimen. The amount of Lu2SiO5 phase at the surface of specimen increased with the increase of gas temperature or water vapor partial pressure. A corresponding decrease in the amount of Lu2Si2O7 phase was observed. Furthermore, by using the average weight loss rate for exposure times of ten hours, the influence of gas temperature and water vapor partial pressure on weight loss rate was examined, and the amount of recession under gas turbine conditions was calculated.

Coal Ash Deposition on Nozzle Guide Vanes: Part I—Experimental Characteristics of Four Coal Ash Types

2011 ◽  
Author(s):  
J. Webb ◽  
B. Casaday ◽  
B. Barker ◽  
J. P. Bons ◽  
A. D. Gledhill ◽  
...  
Keyword(s):  
Film Cooling ◽  
Gas Flow ◽  
Guide Vane ◽  
Ambient Pressure ◽  
Coal Ash ◽  
Leading Edge ◽  
Operating Conditions ◽  
Test Facility ◽  
Gas Temperature ◽  
Nozzle Guide

An accelerated deposition test facility was operated with three different coal ash species to study the effect of ash composition on deposition rate and spatial distribution. The facility seeds a combusting (natural gas) flow with 10–20 micron mass mean diameter coal ash particulate. The particulate-laden combustor exhaust is accelerated through a rectangular-to-annular transition duct and expands to ambient pressure through a nozzle guide vane annular sector. For the present study, the annular cascade consisted of two CFM56 aero-engine vane doublets; comprising three full passages and two half passages of flow. The inlet Mach number (0.1) and gas temperature (1100°C) are representative of operating turbines. Ash samples were tested from the three major coal ranks: lignite, subbituminous, and bituminous. Investigations over a range of inlet gas temperatures from 900°C to 1120°C showed that deposition increased with temperature, though the threshold for deposition varied with ash type. Deposition levels varied with coal rank, with lignite producing the largest deposits at the lowest temperature. Regions of heightened deposition were noted; the leading edge and pressure surface being particularly implicated. Scanning electron microscopy was used to identify deposit structure. For a limited subset of tests, film cooling was employed at nominal design operating conditions but provided minimal protection in cases of severe deposition.

Coal Ash Deposition on Nozzle Guide Vanes—Part I: Experimental Characteristics of Four Coal Ash Types

2012 ◽  
Vol 135 (2) ◽  
Author(s):  
J. Webb ◽  
B. Casaday ◽  
B. Barker ◽  
J. P. Bons ◽  
A. D. Gledhill ◽  
...  
Keyword(s):  
Film Cooling ◽  
Gas Flow ◽  
Guide Vane ◽  
Ambient Pressure ◽  
Coal Ash ◽  
Leading Edge ◽  
Operating Conditions ◽  
Test Facility ◽  
Gas Temperature ◽  
Nozzle Guide

An accelerated deposition test facility was operated with four different coal ash species to study the effect of ash composition on deposition rate and spatial distribution. The facility seeds a combusting (natural gas) flow with 10–20 micron mass mean diameter coal ash particulate. The particulate-laden combustor exhaust is accelerated through a rectangular-to-annular transition duct and expands to ambient pressure through a nozzle guide vane annular sector. For the present study, the annular cascade consisted of two CFM56 aero-engine vane doublets, comprising three full passages and two half passages of flow. The inlet Mach number (0.1) and gas temperature (1100 °C) are representative of operating turbines. Ash samples were tested from the three major coal ranks: lignite, subbituminous, and bituminous. Investigations over a range of inlet gas temperatures from 900 °C to 1120 °C showed that deposition increased with temperature, though the threshold for deposition varied with ash type. Deposition levels varied with coal rank, with lignite producing the largest deposits at the lowest temperature. Regions of heightened deposition were noted; the leading edge and pressure surface being particularly implicated. Scanning electron microscopy was used to identify deposit structure. For a limited subset of tests, film cooling was employed at nominal design operating conditions but provided minimal protection in cases of severe deposition.

Hypocycloid Gear Mechanism Versus Slider-Crank Mechanism in Engines

2019 ◽  
Author(s):  
Mostafa A. ElBahloul ◽  
ELsayed S. Aziz ◽  
Constantin Chassapis
Keyword(s):  
Gas Flow ◽  
Combustion Engine ◽  
Gear Train ◽  
Cylinder Wall ◽  
Power Losses ◽  
Connecting Rod ◽  
Combustion Gas ◽  
Standard Design ◽  
Gear Mechanism ◽  
Crank Mechanism

Abstract This effort investigates the feasibility of using the Hypocycloid Gear Mechanism (HGM) as an alternative to the conventional slider-crank mechanism for Internal Combustion Engine (ICE) applications. Engines incorporating the conventional slider-crank mechanism are subjected to high frictional power losses mainly due to the piston-rod assembly and the associated complex motion of the connecting rod. The unique HGM engine provides the means for the piston-rod assembly to reciprocate in a straight-line motion along the cylinder axis, thus eliminating the piston side-thrusting into the cylinder wall. To analyze the performance advantages of the HGM engine, a Matlab/Simulink model is developed for the simulation of a single-cylinder HGM engine from the throttle to the crankshaft output. The model integrates several sub-models for combustion, gas flow, heat transfer, and friction power loss of the internal gear train meshes, rolling bearings, and sliding bearings. The design of the planetary crank gearing system to satisfy the design specifications of ICE, has been derived using standard design procedures provided by AGMA. Calculated efficiency and power diagrams are plotted and compared with the performance of conventional engines in the literature. The results show that the HGM can satisfy modern ICE design requirements, achieve better engine performance characteristics, and minimize the frictional power losses. The HGM engine achieved lower frictional power losses by an average 33% of the conventional engine losses while its mechanical efficiency is enhanced by up to +24% with respect to the conventional engine.

A Methodology and Case Study of Outboard Traverse Flame Detection on Aeroderivative Gas Turbines

2019 ◽  
Author(s):  
Jean-Roch Jacques ◽  
Noor Azman Mohamat Nor
Keyword(s):  
Gas Turbines ◽  
Life Cycle Cost ◽  
Gas Flow ◽  
Poor Quality ◽  
Outer Radius ◽  
Dual Immersion ◽  
Gas Temperature ◽  
Combustion Gas ◽  
Immersion Thermocouple ◽  
Flame Detection

Abstract Outboard-traverse flame migration in an annular profile, combustion gas pathway of a Siemens aero-derivative turbine engine can be detected with a dual immersion thermocouple. This solution is applicable for Oil & Gas operators using gas turbines fueled by natural gas. The typical flame profile within the annular combustion gas flow path is disturbed by introducing poor quality fuel into the engine. The skewed or outward bias flame profile in turn causes severe overheating of the hot section components around the outer radius of the annular combustor exit wall covering a number of hot section components. This ultimately causes accelerated components deterioration and failure to meet its target design life. Consequently, resulting in rejection of these components and increasing the life cycle cost of their asset operations. The introduction of the dual immersion thermocouple allow us to detect outward bias flame pattern using the exhaust gas temperature profile during operation and warn the operator of this condition via software alarm and trip provision. By implementing a means of detecting outward bias flame patterns, the operator will be made aware of this condition and can then take means to resolve this matter by first, allowing to optimize hot section components boundary limits and saving overhaul costs and second, avoid unplanned maintenance outages due to hot section premature failures.

Developments in Hot-Streak Simulators for Turbine Testing

2009 ◽  
Vol 131 (3) ◽  
Author(s):  
Thomas Povey ◽  
Imran Qureshi
Keyword(s):  
Temperature Profile ◽  
Gas Injection ◽  
Test Facility ◽  
Inlet Temperature ◽  
Temperature Profiles ◽  
Gas Temperature ◽  
High Pressure Turbine ◽  
Injection Temperature ◽  
Hot Streak ◽  
The Impact

The importance of understanding the impact of hot-streaks, and temperature distortion in general, on the high pressure turbine is widely appreciated, although it is still generally the case that turbines are designed for uniform inlet temperature—often the predicted peak gas temperature. This is because there is an insufficiency of reliable experimental data both from operating combustors and from rotating turbine experiments in which a combustor representative inlet temperature profile has accurately been simulated. There is increasing interest, therefore, in experiments that attempt to address this deficiency. Combustor (hot-streak) simulators have been implemented in six rotating turbine test facilities for the study of the effects on turbine life, heat transfer, aerodynamics, blade forcing, and efficiency. Three methods have been used to simulate the temperature profile: (a) the use of foreign gas to simulate the density gradients that arise due to temperature differences, (b) heat exchanger temperature distortion generators, and (c) cold gas injection temperature distortion generators. Since 2004 three significant new temperature distortion generators have been commissioned, and this points to the current interest in the field. The three new distortion generators are very different in design. The generator designs are reviewed, and the temperature profiles that were measured are compared in the context of the available data from combustors, which are also collected. A universally accepted terminology for referring to and quantifying temperature distortion in turbines has so far not developed, and this has led to a certain amount of confusion regarding definitions and terminology, both of which have proliferated. A simple means of comparing profiles is adopted in the paper and is a possible candidate for future use. New whole-field combustor measurements are presented, and the design of an advanced simulator, which has recently been commissioned to simulate both radial and circumferential temperature nonuniformity profiles in the QinetiQ/Oxford Isentropic Light Piston Turbine Test Facility, is presented.

scholarly journals Numerical Calculations of WR-40 Boiler Based on its Zero-Dimensional Model

2014 ◽  
Vol 35 (2) ◽  
pp. 173-180 ◽  
Author(s):  
Bartłomiej Hernik
Keyword(s):  
Numerical Model ◽  
Flue Gases ◽  
Balance Model ◽  
Furnace Chamber ◽  
Gas Temperature ◽  
Cfd Modelling ◽  
Boiler Furnace ◽  
Average Temperature ◽  
Furnace Outlet ◽  
Dissipation Model

Abstract Generally, the temperature of flue gases at the furnace outlet is not measured. Therefore, a special computation procedure is needed to determine it. This paper presents a method for coordination of the numerical model of a pulverised fuel boiler furnace chamber with the measuring data in a situation when CFD calculations are made in regard to the furnace only. This paper recommends the use of the classical 0-dimensional balance model of a boiler, based on the use of measuring data. The average temperature of flue gases at the furnace outlet tk" obtained using the model may be considered as highly reliable. The numerical model has to show the same value of tk" . This paper presents calculations for WR-40 boiler. The CFD model was matched to the 0-dimensional tk" value by means of a selection of the furnace wall emissivity. As a result of CFD modelling, the flue gas temperature and the concentration of CO, CO2, O2 and NOx were obtained at the furnace chamber outlet. The results of numerical modelling of boiler combustion based on volumetric reactions and using the Finite-Rate/Eddy-Dissipation Model are presented.

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