Improving the Performance of a Bent Ejector With Inlet Swirl

2008 ◽  
Vol 130 (6) ◽  
Author(s):  
Asim Maqsood ◽  
A. M. Birk
Keyword(s):  
Gas Turbine ◽  
Pressure Rise ◽  
Total Efficiency ◽  
Exhaust Gas ◽  
Primary Flow ◽  
Inlet Swirl ◽  
Gas Turbine Exhaust ◽  
Turbine Exhaust ◽  
Exhaust Systems

Ejectors are commonly employed in gas turbine exhaust systems for reasons such as space ventilation and IR suppression. Ejectors may incorporate bends in the geometry for various reasons. Studies have shown that the bend has a deteriorating effect on the performance of an ejector. This work was aimed to investigate the effect of exhaust gas swirl on improving the performance of a bent ejector. Four short oblong ejectors with different degrees of bend in the mixing tube and four swirl conditions were tested in this study. The primary nozzle, in all cases, was composed of a circular to oblong transition. Testing was performed at ambient and hot primary flow with 0deg, 10deg, 20deg, and 30deg swirl angles. It was observed that the swirl had a strong affect on the performance of a bent ejector. Improvement of up to 55%, 96%, and 180% was obtained in the pumping ratio, pressure rise, and total efficiency, respectively, with a 20deg swirl in the exhaust gas.

Improving the Performance of a Bent Ejector With Inlet Swirl

2008 ◽  
Author(s):  
Asim Maqsood ◽  
A. M. Birk
Keyword(s):  
Gas Turbine ◽  
Pressure Rise ◽  
Total Efficiency ◽  
Exhaust Gas ◽  
Primary Flow ◽  
Inlet Swirl ◽  
Gas Turbine Exhaust ◽  
Turbine Exhaust ◽  
Exhaust Systems

Ejectors are commonly employed in gas turbine exhaust systems for reasons such as space ventilation and IR suppression. Ejectors may incorporate bends in the geometry for various reasons. Studies have shown that the bend has a deteriorating effect on the performance of an ejector. This work was aimed to investigate the effect of exhaust gas swirl on improving the performance of a bent ejector. Four short oblong ejectors with different degrees of bend in the mixing tube and four swirl conditions were tested in this study. The primary nozzle, in all the cases, was composed of a circular to oblong transition. Testing was performed at ambient and hot primary flow with 0, 10, 20 and 30° swirl angles. It was observed that the swirl had a strong affect on the performance of a bent ejector. Improvement of up to 55, 96 and 180% was obtained in the pumping ratio, pressure rise and total efficiency respectively with a 20° swirl in the exhaust gas.

Prediction of Pressure Rise in a Gas Turbine Exhaust Duct Under Flameout Scenarios While Operating On Hydrogen and Natural Gas Blends

2021 ◽  
Author(s):  
Orlando Ugarte ◽  
Suresh Menon ◽  
Wayne Rattigan ◽  
Paul Winstanley ◽  
Priyank Saxena ◽  
...  
Keyword(s):  
Natural Gas ◽  
Gas Turbine ◽  
Combustion Process ◽  
Pressure Rise ◽  
Combustion Model ◽  
Computational Domain ◽  
Cfd Model ◽  
Exhaust Duct ◽  
Gas Turbine Exhaust ◽  
Turbine Exhaust

Abstract In recent years, there is a growing interest in blending hydrogen with natural gas fuels to produce low carbon electricity. It is important to evaluate the safety of gas turbine packages under these conditions, such as late-light off and flameout scenarios. However, the assessment of the safety risks by performing experiments in full-scale exhaust ducts is a very expensive and, potentially, risky endeavor. Computational simulations using a high fidelity CFD model provide a cost-effective way of assessing the safety risk. In this study, a computational model is implemented to perform three dimensional, compressible and unsteady simulations of reacting flows in a gas turbine exhaust duct. Computational results were validated against data obtained at the simulated conditions in a representative geometry. Due to the enormous size of the geometry, special attention was given to the discretization of the computational domain and the combustion model. Results show that CFD model predicts main features of the pressure rise driven by the combustion process. The peak pressures obtained computationally and experimentally differed in 20%. This difference increased up to 45% by reducing the preheated inflow conditions. The effects of rig geometry and flow conditions on the accuracy of the CFD model are discussed.

scholarly journals High-Temperature Profile Monitoring in Gas Turbine Exhaust-Gas Diffusors with Six-Point Fiber-Optic Sensor Array

2020 ◽  
Vol 5 (4) ◽  
pp. 25
Author(s):  
Franz J. Dutz ◽  
Sven Boje ◽  
Ulrich Orth ◽  
Alexander W. Koch ◽  
Johannes Roths
Keyword(s):  
Gas Turbine ◽  
Fiber Optic ◽  
Characteristic Temperature ◽  
Fiber Optic Sensor ◽  
Exhaust Gas ◽  
Radial Temperature ◽  
Temperature Probe ◽  
Steel Protection ◽  
Gas Turbine Exhaust ◽  
Turbine Exhaust

In this paper, the deployment of a newly developed, multipoint, fiber-optic temperature-sensor system for temperature distribution measurements in a 6 MW gas turbine is demonstrated. The optical sensor fiber was integrated in a stainless steel protection cable with a 1.6 mm outside diameter. It included six measurement points, distributed over a length of 110 mm. The sensor cable was mounted in a temperature probe and was positioned radially in the exhaust-gas diffusor of the turbine. With this temperature probe, the radial temperature profiles in the exhaust-gas diffusor were measured with high spatial and temporal resolution. During a test run of the turbine, characteristic temperature gradients were observed when the machine operated at different loads.

scholarly journals A Fault Diagnosis Approach for Gas Turbine Exhaust Gas Temperature Based on Fuzzy C-Means Clustering and Support Vector Machine

2015 ◽  
Vol 2015 ◽  
pp. 1-11 ◽  
Author(s):  
Zhi-tao Wang ◽  
Ning-bo Zhao ◽  
Wei-ying Wang ◽  
Rui Tang ◽  
Shu-ying Li
Keyword(s):  
Fault Diagnosis ◽  
Gas Turbine ◽  
Clustering Algorithm ◽  
Support Vector ◽  
Exhaust Gas ◽  
Gas Temperature ◽  
Fcm Clustering ◽  
Gas Turbine Exhaust ◽  
Exhaust Gas Temperature ◽  
Turbine Exhaust

As an important gas path performance parameter of gas turbine, exhaust gas temperature (EGT) can represent the thermal health condition of gas turbine. In order to monitor and diagnose the EGT effectively, a fusion approach based on fuzzy C-means (FCM) clustering algorithm and support vector machine (SVM) classification model is proposed in this paper. Considering the distribution characteristics of gas turbine EGT, FCM clustering algorithm is used to realize clustering analysis and obtain the state pattern, on the basis of which the preclassification of EGT is completed. Then, SVM multiclassification model is designed to carry out the state pattern recognition and fault diagnosis. As an example, the historical monitoring data of EGT from an industrial gas turbine is analyzed and used to verify the performance of the fusion fault diagnosis approach presented in this paper. The results show that this approach can make full use of the unsupervised feature extraction ability of FCM clustering algorithm and the sample classification generalization properties of SVM multiclassification model, which offers an effective way to realize the online condition recognition and fault diagnosis of gas turbine EGT.

On the Effect of Swirl Flow of Gas Turbine Exhaust Gas in an Inlet Duct of Heat Recovery Steam Generator

2002 ◽  
Vol 124 (3) ◽  
pp. 496-502 ◽  
Author(s):  
B. E. Lee ◽  
S. B. Kwon ◽  
C. S. Lee
Keyword(s):  
Gas Turbine ◽  
Steam Generator ◽  
Heat Recovery ◽  
Swirl Flow ◽  
Exhaust Gas ◽  
Heat Recovery Steam Generator ◽  
Gas Turbine Exhaust ◽  
Duct Burner ◽  
Turbine Exhaust ◽  
Inlet Duct

Computational and experimental studies are performed to investigate the effect of swirl flow of gas turbine exhaust gas (GTEG) in an inlet duct of a heat recovery steam generator (HRSG). A supplemental-fired HRSG is chosen as the model studied because the uniformity of the GTEG at the inlet plane of the duct burner is essential in such applications. Both velocity and oxygen distributions are investigated at the inlet plane of the duct burner installed in the middle of the HRSG transition duct. Two important parameters, the swirl angle of GTEG and the momentum ratio of additional air to GTEG, are chosen for the investigation of mixing between the two streams. It has been found that a flow correction device (FCD) is essential to provide a uniform gas flow distribution at the inlet plane of the duct burner.

NOx Removal Process by Injection of NH3 and H2O2 in Gas Turbine Exhaust Gas

1979 ◽  
Author(s):  
Y. Hishinuma ◽  
F. Nakajima ◽  
H. Akimoto ◽  
Y. Uchiyama ◽  
S. Azuhata ◽  
...  
Keyword(s):  
Gas Turbine ◽  
Nox Reduction ◽  
Reduction Rate ◽  
Reduction Process ◽  
Heterogeneous Reactions ◽  
High Rate ◽  
Exhaust Gas ◽  
Reduction Of Nox ◽  
Gas Turbine Exhaust ◽  
Turbine Exhaust

For the removal of NOx in a gas turbine exhaust gas, the reduction of NOx with NH3 and H2O2 was studied. It was found that the addition of H2O2 very effectively lowers the reduction temperature of NO with NH3 and that more than 90 percent NOx reduction could be attained at 550 C in the absence of O2. However, the NOx reduction rate decreased with increases in the concentration of O2, and NOx reduction was about 40 to 60 percent under gas turbine exhaust gas condition (15 percent O2). In order to attain a high rate of reduction of NOx, a combined reduction process, which consisted of homogeneous gas phase and the catalytic heterogeneous reactions, was also developed. The efficiency of the new process was proved in a pilot plant using half a size model of a 25-MW gas turbine combustor.

Prediction of Pressure Rise in a Gas Turbine Exhaust Duct Under Flameout Scenarios While Operating on Hydrogen and Natural Gas Blends

2021 ◽  
Author(s):  
Orlando Ugarte ◽  
Suresh Menon ◽  
Wayne Rattigan ◽  
Paul Winstanley ◽  
Priyank Saxena ◽  
...  
Keyword(s):  
Natural Gas ◽  
Gas Turbine ◽  
Combustion Process ◽  
Pressure Rise ◽  
Combustion Model ◽  
Computational Domain ◽  
Cfd Model ◽  
Exhaust Duct ◽  
Gas Turbine Exhaust ◽  
Turbine Exhaust

Abstract In recent years, there is a growing interest in blending hydrogen with natural gas fuels to produce low carbon electricity. It is important to evaluate the safety of gas turbine packages under these conditions, such as late-light off and flameout scenarios. However, the assessment of the safety risks by performing experiments in full-scale exhaust ducts is a very expensive and, potentially, risky endeavor. Computational simulations using a high fidelity CFD model provide a cost-effective way of assessing the safety risk. In this study, a computational model is implemented to perform three dimensional, compressible and unsteady simulations of reacting flows in a gas turbine exhaust duct. Computational results were validated against data obtained at the simulated conditions in a representative geometry. Due to the enormous size of the geometry, special attention was given to the discretization of the computational domain and the combustion model. Results show that CFD model predicts main features of the pressure rise driven by the combustion process. The peak pressures obtained computationally and experimentally differed in 20%. This difference increased up to 45% by reducing the preheated inflow conditions. The effects of rig geometry and flow conditions on the accuracy of the CFD model are discussed.

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