Experimental Results of Full Scale Air-Cooled Turbine Tests

1976 ◽  
Vol 98 (1) ◽  
pp. 103-113
Author(s):  
H. Nouse ◽  
A. Yamamoto ◽  
T. Yoshida ◽  
H. Nishimura ◽  
K. Takahara ◽  
...  

In order to investigate several problems associated with the turbine cooling, an air-cooled two-stage axial flow turbine for an aircraft engine application was designed. Aerodynamic characteristics of the two-stage turbine without coolants were obtained first from the cold air turbine tests, and predictions of the turbine performance with supplying of coolants were made using the test results. Following these experiments, cooling tests of the first stage turbine were conducted in the range of turbine inlet gas temperatures lower than 1360 K by the another test apparatus. The descriptions of the turbine and the two test apparatus and the experimental results of the two test turbines are presented. The performance prediction, coolant effects and Reynolds number effect on the turbine performance are also described.

2020 ◽  
Vol 12 (12) ◽  
pp. 168781402098437
Author(s):  
Liu Jiang ◽  
Guo Zhiping ◽  
Miao Shujing ◽  
He Xiangxin ◽  
Zhu Xinyu

In order to meet the requirements of output torque, efficiency and compact shape of micro-spindles for small parts machining, a two-stage axial micro air turbine spindle with an axial inlet and outlet is proposed. Based on the k-ω turbulence model of SST, the flow field and operation characteristics of the two-stage axial micro air turbine spindle were studied using computational fluid dynamics (CFD) combined with an experimental study. We obtained the air turbine spindle under different working conditions of the loss and torque characteristics. When the inlet pressure was 300 KPa, the output speed of the two-stage turbine was 100,000 rpm, 9% higher than that of a single-stage turbine output torque. The total torque reached 6.39 N·mm, and the maximum efficiency of the turbine and the spindle were 42.2% and 32.3%, respectively. Through the research on the innovative structure of the two-stage axial micro air turbine spindle, the overall performance of the principle prototype has been significantly improved and the problems of insufficient output torque and low working efficiency in high-speed micro-machining can be solved practically, which laid a solid foundation for improving the machining efficiency of small parts and reducing the size of micro machine tool.


Energies ◽  
2021 ◽  
Vol 14 (5) ◽  
pp. 1382
Author(s):  
Obida Zeitoun

Gas turbine inlet air-cooling (TIAC) is an established technology for augmenting gas turbine output and efficiency, especially in hot regions. TIAC using evaporative cooling is suitable for hot, dry regions; however, the cooling is limited by the ambient wet-bulb temperature. This study investigates two-stage evaporative TIAC under the harsh weather of Riyadh city. The two-stage evaporative TIAC system consists of indirect and direct evaporative stages. In the indirect stage, air is precooled using water cooled in a cooling tower. In the direct stage, adiabatic saturation cools the air. This investigation was conducted for the GE 7001EA gas turbine model. Thermoflex software was used to simulate the GE 7001EA gas turbine using different TIAC systems including evaporative, two-stage evaporative, hybrid absorption refrigeration evaporative and hybrid vapor-compression refrigeration evaporative cooling systems. Comparisons of different performance parameters of gas turbines were conducted. The added annual profit and payback period were estimated for different TIAC systems.


Author(s):  
Takeshi Yamamoto ◽  
Kazuo Shimodaira ◽  
Seiji Yoshida ◽  
Yoji Kurosawa

The Japan Aerospace Exploration Agency (JAXA) is conducting research and development on aircraft engine technologies to reduce environmental impact for the TechCLEAN project. As a part of the project, combustion technologies have been developed with an aggressive target that is an 80% reduction over the NOx threshold of the ICAO CAEP/4 standard. A staged fuel nozzle with a pilot mixer and a main mixer was developed and tested using a single-sector combustor under the target engine’s LTO cycle conditions with a rated output of 40 kN and an overall pressure ratio of 25.8. The test results showed a 77% reduction over the CAEP/4 NOx standard. A reduction in smoke was found under a higher thrust condition than the 30% MTO condition, and a reduction in CO emission was found under a lower thrust condition than the 85% MTO condition. In the present study, an additional fuel burner was designed and tested with the staged fuel nozzle in a single-sector combustor to control emissions. The test results show that the combustor enables an 82% reduction in NOx emissions relative to the ICAO CAEP/4 standard and a drastic reduction in smoke and CO emissions.


1983 ◽  
Vol 105 (1) ◽  
pp. 125-129
Author(s):  
Baoshi Chen ◽  
Tianyi Zhang

Test results obtained from a two-stage fan are analysed and the reasons that caused the design performance target not to be attained are presented in this paper. Addition of a partspan shroud on rotor 1 caused higher losses and changed radial distribution of parameters. Modification on the flowpath and chord length of stator 1 resulted in excessively high inlet Mach number and flow separation in the hub region. The high load and high incidence at the hub of rotor 2 caused higher losses and reduced stall margin of the fan.


Author(s):  
Farrokh Zarifi-Rad ◽  
Hamid Vajihollahi ◽  
James O’Brien

Scale models give engineers an excellent understanding of the aerodynamic behavior behind their design; nevertheless, scale models are time consuming and expensive. Therefore computer simulations such as Computational Fluid Dynamics (CFD) are an excellent alternative to scale models. One must ask the question, how close are the CFD results to the actual fluid behavior of the scale model? In order to answer this question the engineering team investigated the performance of a large industrial Gas Turbine (GT) exhaust diffuser scale model with performance predicted by commercially available CFD software. The experimental results were obtained from a 1:12 scale model of a GT exhaust diffuser with a fixed row of blades to simulate the swirl generated by the last row of turbine blades five blade configurations. This work is to validate the effect of the turbulent inlet conditions on an axial diffuser, both on the experimental front and on the numerical analysis approach. The object of this work is to bring forward a better understanding of velocity and static pressure profiles along the gas turbine diffusers and to provide an accurate experimental data set to validate the CFD prediction. For the CFD aspect, ANSYS CFX software was chosen as the solver. Two different types of mesh (hexagonal and tetrahedral) will be compared to the experimental results. It is understood that hexagonal (HEX) meshes are more time consuming and more computationally demanding, they are less prone to mesh sensitivity and have the tendancy to converge at a faster rate than the tetrahedral (TET) mesh. It was found that the HEX mesh was able to generate more consistent results and had less error than TET mesh.


2021 ◽  
pp. 106953
Author(s):  
Penghui Sun ◽  
Xiande Fang ◽  
Fengting Zhuang ◽  
Chuang Chen ◽  
Hongfeng Shang ◽  
...  

Author(s):  
Takeshi Yamamoto ◽  
Kazuo Shimodaira ◽  
Seiji Yoshida ◽  
Yoji Kurosawa

The Japan Aerospace Exploration Agency (JAXA) is conducting research and development on aircraft engine technologies to reduce environmental impact for the Technology Development Project for Clean Engines (TechCLEAN). As a part of the project, combustion technologies have been developed with an aggressive target that is an 80% reduction over the NOx threshold of the International Civil Aviation Organization (ICAO) Committee on Aviation Environmental Protection (CAEP)/4 standard. A staged fuel nozzle with a pilot mixer and a main mixer was developed and tested using a single-sector combustor under the target engine's landing and takeoff (LTO) cycle conditions with a rated output of 40 kN and an overall pressure ratio of 25.8. The test results showed a 77% reduction over the CAEP/4 NOx standard. However, the reduction in smoke at thrust conditions higher than the 30% MTO condition and of CO emission at thrust conditions lower than the 85% MTO condition are necessary. In the present study, an additional fuel burner was designed and tested with the staged fuel nozzle in a single-sector combustor to control emissions. The test results show that the combustor enables an 82% reduction in NOx emissions relative to the ICAO CAEP/4 standard and a drastic reduction in smoke and CO emissions.


2011 ◽  
Vol 243-249 ◽  
pp. 258-262
Author(s):  
Jun Chen ◽  
Jia Lv ◽  
Qi Lin Zhang ◽  
Zhi Xiong Tao ◽  
Jun Chen

Laminated glass has been increasing widely used in high rise buildings as a kind of safety glass in recent years. So we should analyze its material property. In this paper, we use flexural experiments and ANSYS program to analyze the main factors that affect the flexural capacity of the laminated glass. The test results show that the flexural capacity is closely related to film. And the ANSYS program had got good agreement with the experimental results. Comparison of experimental results with calculated ones indicates that the current design code will lead to conservative results and the equivalent thickness of laminated glasses provided in the code should be further discussed.


2021 ◽  
Vol 12 (5) ◽  
pp. 1-25
Author(s):  
Shengwei Ji ◽  
Chenyang Bu ◽  
Lei Li ◽  
Xindong Wu

Graph edge partitioning, which is essential for the efficiency of distributed graph computation systems, divides a graph into several balanced partitions within a given size to minimize the number of vertices to be cut. Existing graph partitioning models can be classified into two categories: offline and streaming graph partitioning models. The former requires global graph information during the partitioning, which is expensive in terms of time and memory for large-scale graphs. The latter creates partitions based solely on the received graph information. However, the streaming model may result in a lower partitioning quality compared with the offline model. Therefore, this study introduces a Local Graph Edge Partitioning model, which considers only the local information (i.e., a portion of a graph instead of the entire graph) during the partitioning. Considering only the local graph information is meaningful because acquiring complete information for large-scale graphs is expensive. Based on the Local Graph Edge Partitioning model, two local graph edge partitioning algorithms—Two-stage Local Partitioning and Adaptive Local Partitioning—are given. Experimental results obtained on 14 real-world graphs demonstrate that the proposed algorithms outperform rival algorithms in most tested cases. Furthermore, the proposed algorithms are proven to significantly improve the efficiency of the real graph computation system GraphX.


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