Effect of inlet temperature on combustion efficiency of lean H2/air mixtures in a micro-combustor with wall cavities

2016 ◽  
Vol 107 ◽  
pp. 837-843 ◽  
Author(s):  
Wei Yang ◽  
Aiwu Fan ◽  
Hong Yao
Keyword(s):  
Combustion Efficiency ◽  
Inlet Temperature ◽  
Micro Combustor

Experimental Study of Combustion on a Micro Gas Turbine Combustor

2008 ◽  
Author(s):  
Feng-Shan Wang ◽  
Wen-Jun Kong ◽  
Bao-Rui Wang
Keyword(s):  
Gas Turbine ◽  
Pressure Loss ◽  
Loss Factor ◽  
Total Pressure ◽  
Combustion Efficiency ◽  
Total Pressure Loss ◽  
Test Facility ◽  
Inlet Temperature ◽  
Micro Gas Turbine ◽  
Oil Fuel

A research program is in development in China as a demonstrator of combined cooling, heating and power system (CCHP). In this program, a micro gas turbine with net electrical output around 100kW is designed and developed. The combustor is designed for natural gas operation and oil fuel operation, respectively. In this paper, a prototype can combustor for the oil fuel was studied by the experiments. In this paper, the combustor was tested using the ambient pressure combustor test facility. The sensors were equipped to measure the combustion performance; the exhaust gas was sampled and analyzed by a gas analyzer device. From the tests and experiments, combustion efficiency, pattern factor at the exit, the surface temperature profile of the outer liner wall, the total pressure loss factor of the combustion chamber with and without burning, and the pollutants emission fraction at the combustor exit were obtained. It is also found that with increasing of the inlet temperature, the combustion efficiency and the total pressure loss factor increased, while the exit pattern factor coefficient reduced. The emissions of CO and unburned hydrogen carbon (UHC) significantly reduced, but the emission of NOx significantly increased.

scholarly journals Comparison of Various Fluidized Bed Combustor-Gas Turbine Systems

1985 ◽  
Author(s):  
Arthur P. Fraas
Keyword(s):  
Gas Turbine ◽  
Fluidized Bed ◽  
Thermal Efficiency ◽  
Combustion Efficiency ◽  
Capital Cost ◽  
Inlet Temperature ◽  
Extensive Experience ◽  
Helium Gas ◽  
Steam Plant ◽  
Fluidized Bed Combustor

Pressurizing a fluidized bed combustor with a gas turbine greatly improves both sulfur retention and combustion efficiency. Operating the gas turbine with a high inlet temperature (e.g. 900°C) would yield a thermal efficiency about four points higher than for an atmospheric furnace, but 40 y of experience have failed to solve problems with flyash erosion and deposits. Extensive experience such as that with fluidized bed catalytic cracking units indicates that the gas turbine blade erosion and deposit problems can be handled by dropping the turbine inlet temperature below 400°C where the turbine delivers just enough power to drive the compressor. The resulting thermal efficiency is about half a point higher than for an atmospheric bed, and the capital cost of the FBC-related components is about 40% lower. While a closed-cycle helium gas turbine might be used rather than a steam cycle, the thermal efficiency would be about four points lower and the capital cost of the FBC-related components would be roughly twice that for the corresponding steam plant.

scholarly journals Reduced NOx Emissions Using Low Radial Swirler Vane Angles

1991 ◽  
Author(s):  
H. S. Alkabie ◽  
G. E. Andrews
Keyword(s):  
Gas Turbines ◽  
Fuel Injection ◽  
Combustion Efficiency ◽  
Inlet Temperature ◽  
Nox Emissions ◽  
Primary Zone ◽  
Industrial Gas Turbines ◽  
Curved Blade ◽  
Swirl Vane ◽  
Vane Angle

The influence of vane angle and hence swirl number of a radial swirler on the weak extinction, combustion inefficiency and NOx emissions was investigated at lean gas turbine combustor primary zone conditions. A 140mm diameter atmospheric pressure low NOx combustor primary zone was developed with a Mach number simulation of 30% and 43% of the combustor air flow into the primary zone through a curved blade radial swirler. The range of radial swirler vane angles was 0–60 degrees and central radially outward fuel injection was used throughout with a 600K inlet temperature. For zero vane angle radially inward jets were formed that impinged and generated a strong outer recirculation. This was found to have much lower NOx characteristics compared with a 45 degree swirler at the same pressure loss. However, the lean stability and combustion efficiency in the near weak extinction region was not as good. With swirl the central recirculation zone enhanced the combustion efficiency. For all the swirl vane angles there was little difference in combustion inefficiency between the swirlers. However, the NOx emissions were reduced at the lowest swirl angles and vane angles in the range 20–30 degrees were considered to be the optimum for central injection. NOx emissions for central injection as low as 5ppm at 15% oxygen and 1 bar were demonstrated for zero swirl and 20 degree swirler vane angle. This would scale to well under 25 ppm at pressure for all current industrial gas turbines.

Conical Grid Plate Flame Stabilizers: Number and Size of Jet Shear Layers

1987 ◽  
Author(s):  
A. F. Ali ◽  
G. E. Andrews
Keyword(s):  
Shear Layer ◽  
Combustion Efficiency ◽  
Shear Layers ◽  
Inlet Temperature ◽  
Flame Stability ◽  
Nox Emissions ◽  
Hole Area ◽  
Grid Plate ◽  
Total Shear ◽  
Better Than

The influence of the number and size of the jet shear layers, at a constant total hole area, was investigated in a propane fuelled conical grid plate flame stabiliser. The combustion inefficiency, NOx and flame stability were determined for shear layer designs with 90, 8 and 4 holes. The total shear layer volume increased as the number of holes was reduced and combustion within these larger shear layers was responsible for the superior flame stability and combustion efficiency, but higher NOx emissions. Large shear layers and hence a small number of holes were necessary to achieve an adequate performance at a 400K inlet temperature, but at 600K the 90 hole system had the best combination of low NOx and combustion inefficiency. However, the 8 hole system had a performance close to the 90 hole system at 600K and better than it at 400K and was concluded to be the preferable design.

Development of a Low NOx Combustor for 300kW-Class Ceramic Gas Turbine (CGT302)

1998 ◽  
Author(s):  
A. Okuto ◽  
T. Kimura ◽  
I. Takehara ◽  
T. Nakashima ◽  
Y. Ichikawa ◽  
...  
Keyword(s):  
Research And Development ◽  
Gas Turbine ◽  
Flow Rate ◽  
Gas Turbines ◽  
Combustion Efficiency ◽  
Development Project ◽  
Pollutant Emissions ◽  
Inlet Temperature ◽  
Outlet Temperature ◽  
Nox Emissions

Research and development project of ceramic gas turbines (CGT) was started in 1988 promoted by the Ministry of International Trade and Industry (MITI) in Japan. The target of the CGT project is development of a 300kW-class ceramic gas turbine with a 42 % thermal efficiency and a turbine inlet temperature (TIT) of 1350°C. Three types of CGT engines are developed in this project. One of the CGT engines, which is called CGT302, is a recuperated two-shaft gas turbine for co-generation use. In this paper, we describe the research and development of a combustor for the CGT302. The project requires a combustor to exhaust lower pollutant emissions than the Japanese regulation level. In order to reduce NOx emissions and achieve high combustion efficiency, lean premixed combustion technology is adopted. Combustion rig tests were carried out using this combustor. In these tests we measured the combustor performance such as pollutant emissions, combustion efficiency, combustor inlet/outlet temperature, combustor inlet pressure and pressure loss through combustor. Of course air flow rate and fuel flow rate are controlled and measured, respectively. The targets for the combustor such as NOx emissions and combustion efficiency were accomplished with sufficient margin in these combustion rig tests. In addition, we report the results of the tests which were carried out to examine effects of inlet air pressure on NOx emissions here.

Low NOx Combustor Research for a Mach 3 Turbojet Concept Validation Test Results

1997 ◽  
Author(s):  
Y. Kinoshita ◽  
T. Oda ◽  
J. Kitajima
Keyword(s):  
Combustion Efficiency ◽  
Inlet Temperature ◽  
Swirl Combustor ◽  
Fuel Injectors ◽  
Validation Test ◽  
Wide Range ◽  
Lean Fuel ◽  
Mach 3 ◽  
High Degree ◽  
Concept Validation

A unique idea of premixture jet swirl combustor (PJSC) was proposed for the ultra low NOx combustor of a Mach 3 turbojet. The combustor installed six simple premixing chambers which were arranged at certain angles to the center axis also to the circumference axis on the combustor dome. This arrangement formed large and strong recirculating flows necessary to stabilize flame at lean fuel air ratio conditions. The fuel mixing study revealed that the radial fuel injectors inserted in a premixing chamber exhibited a high degree of uniformity. Single can combustors of PJSC with three types of main fuel injectors were manufactured for the high temperature and high pressure combustion test program. All combustors performed stable combustion for a wide range of FAR and obtained combustion efficiency of 99.9 % at Mach 3 cruise conditions, namely inlet temperature of 1008 K, inlet pressure of 830 kPa and fuel air ratio of 0.0223. HTHPC-01 combustor, which installed the radial fuel injectors and had long mixing length, presented the best NOx emissions and achieved emission index of 2 g/kg fuel at that design condition. PJSC met the emission goal of HYPR project, and concept validation test was completed in success.

Prediction of Combustion Efficiency and NOx Levels for Diffusion Flame Combustors in HAT Cycles

2002 ◽  
Author(s):  
Alexandr A. Belokon ◽  
Konstantin M. Khritov ◽  
Lev A. Klyachko ◽  
Sergey A. Tschepin ◽  
Vladimir M. Zakharov ◽  
...  
Keyword(s):  
Diffusion Flame ◽  
Atmospheric Pressure ◽  
Flame Temperature ◽  
Combustion Efficiency ◽  
Inlet Temperature ◽  
Preliminary Design ◽  
Test Results ◽  
Loading Parameter ◽  
Design Analyses ◽  
The Impact

Diffusion flame combustor test results are presented for methane firing in steam/air mixtures containing up to 20% steam. The tests were conducted at atmospheric pressure with combustor inlet temperatures up to 700K. Steam and air were fully premixed before combustion. Combustion efficiency and NOX levels were measured. The well-known Θ loading parameter was modified by replacing the combustor inlet temperature with the flame temperature. The flame temperature was defined as the stoichiometric temperature of the steam/air mixture. The combustion efficiency obtained with and without steam correlated nicely with this modified loading parameter. Calculated NOX levels agreed well with the measurements, where NOX was predicted using the flamelet technique. This approach makes it possible to predict combustor efficiencies with steam by using combustor performance data taken without steam. Preliminary design analyses of gas turbine cycles with significant steam addition can now easily include the impact of the steam on combustor performance.

Success of Ammonia-Fired, Regenerator-Heated, Diffusion Combustion Gas Turbine Power Generation and Prospect of Low NOx Combustion With High Combustion Efficiency

2017 ◽  
Author(s):  
Osamu Kurata ◽  
Norihiko Iki ◽  
Takayuki Matsunuma ◽  
Takahiro Inoue ◽  
Taku Tsujimura ◽  
...  
Keyword(s):  
Power Generation ◽  
Gas Turbine ◽  
Combustion Efficiency ◽  
Diffusion Combustion ◽  
Inlet Temperature ◽  
Flame Stability ◽  
Gas Turbine Combustor ◽  
Combustion Gas ◽  
Low Nox Combustion ◽  
The 1960S

To protect against global warming, a massive influx of renewable energy is expected. Although hydrogen is a renewable media, its storage and transportation in large quantity is difficult. Ammonia, however, is a hydrogen energy carrier and carbon-free fuel, and its storage and transportation technology is already established. Although ammonia combustion was studied in the 1960s in the USA, the development of an ammonia combustion gas turbine had been abandoned because combustion efficiency was unacceptably low. Since that time, in the combustion field, ammonia has been thought of as a fuel N additive in the study of NOx formation. Recent demand for hydrogen carrier revives the usage of ammonia combustion, but no one has attempted an actual design setup for ammonia combustion gas turbine power generation. The National Institute of Advanced Industrial Science and Technology (AIST) in Japan successfully performed ammonia-kerosene co-fired gas turbine power generation in 2014, and ammonia-fired gas turbine power generation in 2015. In the facilities, a regenerator-heated, diffusion-combustion micro-gas turbine is used, and its high combustor inlet temperature enables high thermal efficiency of ammonia combustion compared with that of methane combustion. Adoption of the regenerator increased combustor inlet temperature and enhanced flame stability in ammonia-air combustion. Although NOx emission from a gas turbine combustor is high, a Selective Catalytic Reduction (SCR) after gas turbine combustor reduces NOx emission to less than 10 ppm. This means that the ammonia combustion gas turbine design, abandoned in the 1960s for its unacceptably low combustion efficiency, has performed successfully with regenerator and SCR technology. However, the weakness of these facilities was that they required large-size SCR equipment in order to suppress a high concentration of NOx. Although NOx reduction in the combustion process is desirable, low NOx combustion technology is difficult because ammonia had been thought of as a source of fuel-NO. In the case of premixed ammonia-air flame, there exists a low emission window of NOx and NH3 in a certain equivalence ratio, but combustion intensity is very low because the laminar burning velocity of NH3-air is one-fifth that of CH4-air. This means that, when utilizing the window of premixed ammonia-air flame, scale-up of the combustion chamber or fuel additives for enhancement of flame stability is necessary. This study shows that the addition of H2 is effective for low NOx combustion with high combustion efficiency. In addition, H2 can be easily made from NH3 decomposition. The other option is diffusion combustion. Further research on low NOx combustion is needed.

Effects of Inlet Parameters on Combustion Performance in Gas Turbine Combustor

2018 ◽  
Vol 35 (4) ◽  
pp. 339-350
Author(s):  
Yingwen Yan ◽  
Yunpeng Liu ◽  
Liang Huang ◽  
Jinghua Li
Keyword(s):  
Pressure Loss ◽  
Total Pressure ◽  
Combustion Efficiency ◽  
Total Pressure Loss ◽  
Inlet Pressure ◽  
Inlet Temperature ◽  
Gas Turbine Combustor ◽  
Combustion Performance ◽  
Co Emission ◽  
No Emissions

Abstract The effects of different inlet parameters such as inlet temperature and pressure on combustion performance in a single-head combustor were experimentally investigated in this study. The combustion efficiency, total pressure loss, and CO and NO emissions at the outlet of a single-head rectangular combustor with different types of swirlers were separately measured. The experimental results showed that the inlet parameters had obvious effects on the combustion performance, with critical values of 600 K for the inlet temperature and 3.5 bar for the inlet pressure. The combustion efficiency noticeably increased with an increase in the inlet pressure or temperature below these values; however, when either of the inlet parameters was above the critical value, the combustion efficiency was approximately 100 %; that is, the combustion efficiency changed little with an increase in inlet temperate or pressure. When the inlet temperature or pressure increased, NO emission increased but CO emission decreased. By fitting curves to analyze the experimental data, the empirical relationships between the emissions and the inlet temperature were observed to be $CO\; \propto \;{e^{ - T}}, NO\; \propto \;{e^T}$, and those between the emissions and the inlet pressure were $CO\, \propto \,{e^{a + bP + c{P^2}}}, NO\, \propto \,{e^P}$. The total pressure loss increased with the inlet temperature.

Sign in / Sign up

Export Citation Format

Share Document