Enhanced External Aerodynamic Performance of a Generic Combustor Using An Integrated OGV/Prediffuser Design Technique

2006 ◽  
Vol 129 (1) ◽  
pp. 80-87 ◽  
Author(s):  
A. Duncan Walker ◽  
Jon F. Carrotte ◽  
James J. McGuirk
Keyword(s):  
Integrated Design ◽  
Boundary Layer Separation ◽  
Aerodynamic Performance ◽  
Final Report ◽  
Experimental Measurements ◽  
Blade Shape ◽  
Flow Quality ◽  
Overall Performance ◽  
Loss Coefficients

In this paper we use experimental measurements to characterize the extent that improved the external aerodynamic performance (reduced total pressure loss, increased flow quality) of a gas-turbine combustion system may be achieved by adopting an integrated OGV/prediffuser technique. Two OGV/prediffuser combinations were tested. The first is a datum design corresponding to a conventional design approach, where the OGV and prediffuser are essentially designed in isolation. The second is an “integrated” design where the OGV blade shape has been modified, following recommendations of earlier CFD work (Final Report No. TT03R01, 2003), to produce a secondary flow/wake structure that allows the prediffuser to operate at a higher area ratio without boundary layer separation. This is demonstrated to increase static pressure recovery and reduce dump losses. Experimental measurements are presented on a fully annular rig. Several traverse planes are used to gather five-hole probe data that allow the flow structure through the OGV, at the inlet and exit of the prediffuser, and in the inner/outer annulus supply ducts to be examined. Both overall performance measures (loss coefficients) and measures of flow uniformity and quality are used to demonstrate that the integrated design is superior.

Enhanced External Aerodynamic Performance of a Generic Combustor Using an Integrated OGV/Pre-Diffuser Design Technique

2006 ◽  
Author(s):  
A. Duncan Walker ◽  
Jon F. Carrotte ◽  
James J. McGuirk
Keyword(s):  
Integrated Design ◽  
Boundary Layer Separation ◽  
Aerodynamic Performance ◽  
Experimental Measurements ◽  
Flow Uniformity ◽  
Blade Shape ◽  
Flow Quality ◽  
Overall Performance ◽  
Loss Coefficients

The paper uses experimental measurements to characterise the extent that improved external aerodynamic performance (reduced total pressure loss, increased flow quality) of a gas-turbine combustion system may be achieved by adopting an integrated OGV/pre-diffuser technique. Two OGV/pre-diffuser combinations were tested. The first is a datum design corresponding to a conventional design approach, where OGV and pre-diffuser are essentially designed in isolation. The second is an ‘integrated’ design where the OGV blade shape has been modified, following recommendations of earlier CFD work ([14]), to produce a secondary flow/wake structure that allows the pre-diffuser to operate at a higher area ratio without boundary layer separation. This is demonstrated to increase static pressure recovery and reduce dump losses. Experimental measurements are presented on a fully annular rig. Several traverse planes are used to gather 5-hole probe data which allow the flow structure through the OGV, at inlet and exit of the pre-diffuser, and in the inner/outer annulus supply ducts to be examined. Both overall performance measures (loss coefficients) and measures of flow uniformity and quality are used to demonstrate that the integrated design is superior.

Estudio del proceso de lavado de contenedores para eliminar tiempos y movimientos innecesarios, caso: Wash Containers S.A de C.V.

2020 ◽  
pp. 25-36
Author(s):  
Juan Alfredo Lino-Gamiño ◽  
Carlos Méndez-González ◽  
Eduardo José Salazar-Araujo ◽  
Pablo Adrián Magaña-Sánchez
Keyword(s):  
Business Process ◽  
Value Chain ◽  
Process Management ◽  
Core Business ◽  
The Core ◽  
Washing Process ◽  
Overall Performance ◽  
The Times

In the value chain it is important to keep in mind the core business of the company, since it depends largely on the competitiveness of the company and its overall performance, bearing in mind that all business indicators depend on it. In this work we will study the washing process within the company WASH CONTAINERS SA DE CV, to improve the washing processes and in this way reduce times and movements in the process leading the company to reduce costs considerably within the operations company daily, having a more competitive operation and with greater profit margin in its business process. Goals: It Improve the logistics of the movement of containers for washing and with it the core business of the company. Methodology: The action research will be applied applying Business Process Management for the improvement of processes in situ, it will be developed in a certain period of time and with that it will establish an improvement projection. Contribution: The improvement of the times for the disposal of the containers and their subsequent use, allows a better competitiveness and with it the income of the company, on the other hand, the transport companies improve in performance in quantity, quality of disposition and with it their income.

scholarly journals Ensemble-Based Out-of-Distribution Detection

Electronics ◽  
2021 ◽  
Vol 10 (5) ◽  
pp. 567
Author(s):  
Donghun Yang ◽  
Kien Mai Mai Ngoc ◽  
Iksoo Shin ◽  
Kyong-Ha Lee ◽  
Myunggwon Hwang
Keyword(s):  
Detection Method ◽  
State Of The Art ◽  
Metric Learning ◽  
Feature Space ◽  
Confidence Score ◽  
Distance Metric Learning ◽  
Current State ◽  
Overall Performance ◽  
Deep Learning Model

To design an efficient deep learning model that can be used in the real-world, it is important to detect out-of-distribution (OOD) data well. Various studies have been conducted to solve the OOD problem. The current state-of-the-art approach uses a confidence score based on the Mahalanobis distance in a feature space. Although it outperformed the previous approaches, the results were sensitive to the quality of the trained model and the dataset complexity. Herein, we propose a novel OOD detection method that can train more efficient feature space for OOD detection. The proposed method uses an ensemble of the features trained using the softmax-based classifier and the network based on distance metric learning (DML). Through the complementary interaction of these two networks, the trained feature space has a more clumped distribution and can fit well on the Gaussian distribution by class. Therefore, OOD data can be efficiently detected by setting a threshold in the trained feature space. To evaluate the proposed method, we applied our method to various combinations of image datasets. The results show that the overall performance of the proposed approach is superior to those of other methods, including the state-of-the-art approach, on any combination of datasets.

scholarly journals Performance Evaluation of IMERG GPM Products during Tropical Storm Imelda

Atmosphere ◽  
2021 ◽  
Vol 12 (6) ◽  
pp. 687
Author(s):  
Salman Sakib ◽  
Dawit Ghebreyesus ◽  
Hatim O. Sharif
Keyword(s):  
Stage Iv ◽  
Tropical Storm ◽  
Average Correlation ◽  
Acceptable Range ◽  
Precipitation Estimates ◽  
Overall Performance ◽  
Early Late ◽  
Statistical Metrics ◽  
Better Than

Tropical Storm Imelda struck the southeast coastal regions of Texas from 17–19 September, 2019, and delivered precipitation above 500 mm over about 6000 km2. The performance of the three IMERG (Early-, Late-, and Final-run) GPM satellite-based precipitation products was evaluated against Stage-IV radar precipitation estimates. Basic and probabilistic statistical metrics, such as CC, RSME, RBIAS, POD, FAR, CSI, and PSS were employed to assess the performance of the IMERG products. The products captured the event adequately, with a fairly high POD value of 0.9. The best product (Early-run) showed an average correlation coefficient of 0.60. The algorithm used to produce the Final-run improved the quality of the data by removing systematic errors that occurred in the near-real-time products. Less than 5 mm RMSE error was experienced in over three-quarters (ranging from 73% to 76%) of the area by all three IMERG products in estimating the Tropical Storm Imelda. The Early-run product showed a much better RBIAS relatively to the Final-run product. The overall performance was poor, as areas with an acceptable range of RBIAS (i.e., between −10% and 10%) in all the three IMERG products were only 16% to 17% of the total area. Overall, the Early-run product was found to be better than Late- and Final-run.

scholarly journals The design of RIP belts impacts the reliability and quality of the measured respiratory signals

2021 ◽  
Author(s):  
Kristofer Montazeri ◽  
Sigurdur Aegir Jonsson ◽  
Jon Skirnir Agustsson ◽  
Marta Serwatko ◽  
Thorarinn Gislason ◽  
...  
Keyword(s):  
Retrospective Study ◽  
Sleep Apnea ◽  
Automatic Assessment ◽  
Signal Reliability ◽  
Respiratory Airflow ◽  
Flow Quality ◽  
The Mean ◽  
Home Sleep Apnea Testing ◽  
Apnea Testing

Abstract Purpose Evaluate the effect of respiratory inductance plethysmography (RIP) belt design on the reliability and quality of respiratory signals. A comparison of cannula flow to disposable cut-to-fit, semi-disposable folding and disposable RIP belts was performed in clinical home sleep apnea testing (HSAT) studies. Methods This was a retrospective study using clinical HSAT studies. The signal reliability of cannula, thorax, and abdomen RIP belts was determined by automatically identifying periods during which the signals did not represent respiratory airflow and breathing movements. Results were verified by manual scoring. RIP flow quality was determined by examining the correlation between the RIP flow and cannula flow when both signals were considered reliable. Results Of 767 clinical HSAT studies, mean signal reliability of the cut-to-fit, semi-disposable, and disposable thorax RIP belts was 83.0 ± 26.2%, 76.1 ± 24.4%, and 98.5 ± 9.3%, respectively. The signal reliability of the cannula was 92.5 ± 16.1%, 87.0 ± 23.3%, and 85.5 ± 24.5%, respectively. The automatic assessment of signal reliability for the RIP belts and cannula flow had a sensitivity of 50% and a specificity of 99% compared with manual assessment. The mean correlation of cannula flow to RIP flow from the cut-to-fit, semi-disposable, and disposable RIP belts was 0.79 ± 0.24, 0.52 ± 0.20, and 0.86 ± 0.18, respectively. Conclusion The design of RIP belts affects the reliability and quality of respiratory signals. The disposable RIP belts that had integrated contacts and did not fold on top of themselves performed the best. The cut-to-fit RIP belts were most likely to be unreliable, and the semi-disposable folding belts produced the lowest-quality RIP flow signals compared to the cannula flow signal.

Research on the Reliability of Box for Gear Test Bed

2011 ◽  
Vol 121-126 ◽  
pp. 1744-1748
Author(s):  
Xiang Yang Jin ◽  
Tie Feng Zhang ◽  
Li Li Zhao ◽  
He Teng Wang ◽  
Xiang Yi Guan
Keyword(s):  
Power Flow ◽  
Dynamic Performance ◽  
Three Dimensional ◽  
Design Parameters ◽  
The Finite Element Method ◽  
Test Bed ◽  
Kinematics Simulation ◽  
Beveloid Gears ◽  
Overall Performance

To determine the efficiency, load-bearing capacity and fatigue life of beveloid gears with intersecting axes, we design a mechanical gear test bed with closed power flow. To test the quality of its structure and predict its overall performance, we establish a three-dimensional solid model for various components based on the design parameters and adopt the technology of virtual prototyping simulation to conduct kinematics simulation on it. Then observe and verify the interactive kinematic situation of each component. Moreover, the finite element method is also utilized to carry out structural mechanics and dynamics analysis on some key components. The results indicate that the test bed can achieve the desired functionality, and the static and dynamic performance of some key components can also satisfy us.

Tonal Noise Reduction in a Radial Fan With Forward-Curved Blades

2014 ◽  
Author(s):  
Manoochehr Darvish ◽  
Bastian Tietjen ◽  
Daniel Beck ◽  
Stefan Frank
Keyword(s):  
Fluid Dynamics ◽  
Computational Fluid Dynamics ◽  
Aerodynamic Performance ◽  
Computational Aeroacoustics ◽  
Experimental Measurements ◽  
Noise Generation ◽  
Tonal Noise ◽  
Outlet Angle ◽  
And Performance ◽  
Impeller Geometry

The main focus of this work is on the geometrical modifications that can be applied to the fan wheel and the volute tongue of a radial fan to reduce the tonal noise. The experimental measurements are performed by using the in-duct method in accordance with ISO 5136. In addition to the experimental measurements, CFD (Computational Fluid Dynamics) and CAA (Computational Aeroacoustics) simulations are carried out to investigate the effects of different modifications on the noise and performance of the fan. It is shown that by modifying the blade outlet angle, the tonal noise of the fan can be reduced without affecting the performance of the fan. Moreover, it is indicated that increasing the number of blades leads to a significant reduction in the tonal noise and also an improvement in the performance. However, this trend is only valid up to a certain number of blades, and a further increment might reduce the aerodynamic performance of the fan. Besides modifying the impeller geometry, new volute tongues are designed and manufactured. It is demonstrated that the shape of the volute tongue plays an important role in the tonal noise generation of the fan. It is possible to reduce the tonal noise by using stepped tongues which produce phase-shift effects that lead to an effective local cancellation of the noise.

scholarly journals Evaluation of Yield and Quality of Three Jackfruit (Artocarpus heterophyllus L.) Genotypes

2016 ◽  
Vol 14 (1) ◽  
pp. 107-111 ◽  
Author(s):  
M H Rahman ◽  
M M Alam Patwary ◽  
H Barua ◽  
S Nahar ◽  
Abu Noman Faruq Ahmmed
Keyword(s):  
Agricultural Research ◽  
Development Program ◽  
Yield Potential ◽  
Research Station ◽  
Maximum Weight ◽  
Yield And Quality ◽  
Maturity Period ◽  
Minimum Number ◽  
Overall Performance

Yield and quality performances of three jackfruit genotypes were studied at the Agricultural Research Station, Bangladesh Agricultural Research Institute, Pahartali, Chittagong during 2013-2014. Age, growth, maturity period, yield potential and also qualitative characteristics were compared among them.  Based on overall performance with respect to bearing potential, maturity period, fruit and bulb characters, the genotypes AHPah-1 have been found promising for table purpose followed by AHPah-2 and AHPah-3. Minimum days (117) to 1st harvest were observed in AHPah-1. The number of fruits per plant was exceedingly higher (73) in AHPah-1 whereas minimum number (41) was found in AHPah-2. Maximum weight (8.40 kg) per fruit was observed in AHPah-2 and minimum was in AHPah-1(3.40 kg).  The highest single fruit length (37.25cm) was found in AHPah-2 and breadth (27.00cm) was produced by AHPah-3. Maximum number of bulbs (116) was produced in AHPah-1, whereas minimum (63.00) was in AHPah-3. Maximum weight of bulbs per fruit (4.24 kg) was produced in AHPah-2. Individual bulb weight was higher (54.42g) in AHPah -2 whereas, the lowest (16.71) was in AHPah-1. Edible portion was higher (69.27%) in AHPah-1 whereas, the lowest (53.43%) was in AHPah-3. The TSS was the highest (21.00%) in AHPah-1. The highest bulb length and breadth was found in AHPah-3. Highest seeds weight (639g) was produced in AHPah-2. Individual seed weight (8.19 g) was higher in AHPah-2. Therefore, the genotypes can be included in the variety development program after comparing with the already BARI released jackfruit variety.The Agriculturists 2016; 14(1) 107-111

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