Demonstration of a Remotely-Controlled Swirl Generator for Simulating Aircraft Inlet Secondary Flows During Turbine Engine Ground Tests

2018 ◽  
Author(s):  
David Beale
Keyword(s):  
Flight Test ◽  
Test Methods ◽  
Secondary Flows ◽  
Engine Test ◽  
Data Set ◽  
Turbine Engine ◽  
Methodology Development ◽  
Engine Control System ◽  
Swirl Generator ◽  
Wide Range

The development of superior combat aircraft demands the complex integration of the airframe, engine, control system, avionics, and on-board weapon systems. The integration of the engine and the inlet is tantamount to prevailing in an engagement due to the thrust required to execute combat maneuvers. For this reason, test and evaluation methods have been developed to help ensure inlet-engine compatibility by design. The most commonly used methodology characterizes inlet distortion in terms of total-pressure descriptors and correlations. The method includes ground tests employing both wind tunnel and engine test facilities, to acquire the information needed to establish inlet-engine compatibility prior to flight test. Advanced aircraft employing evolving technologies never seen in legacy systems have introduced new challenges to the methodology, and to the ground test methods employed by the methodology. One such challenge arises from the significant flow angularity, or swirl, often found in advanced inlet systems. This paper focuses on the simulation of aircraft inlet swirl during direct-connect turbine engine ground tests. To meet the engine test challenges introduced by advanced aircraft, the Arnold Engineering Development Complex (AEDC) embarked on the development of a swirl generator capable of simulating the different types of swirl expected in future inlet systems over a wide range of swirl angles, and with the ability to remotely set steady-state or transient swirl patterns. The development progressed through a five-step process that culminated in the validation and demonstration of a fully-functional prototype. This paper focuses on the prototype swirl generator and the progression from the establishment of simulation requirements through the prototype validation. Following summaries of each development step, the results of the validation test are presented. The paper also summarizes a recent application of the prototype which not only demonstrated the device in an engine test, but which provided a data set to support swirl methodology development.

Advancements in the Design of an Adaptable Swirl Distortion Generator for Testing Gas Turbine Engines

2009 ◽  
Author(s):  
Yogi Sheoran ◽  
Bruce Bouldin ◽  
P. Murali Krishnan
Keyword(s):  
Gas Turbine ◽  
Fluid Dynamic ◽  
Turbine Engines ◽  
Gas Turbine Engines ◽  
Delta Wings ◽  
Generator System ◽  
Turbine Engine ◽  
Swirl Generator ◽  
Wide Range ◽  
Generator Design

Inlet swirl distortion has recently become a major area of concern in the gas turbine engine community. Gas turbine engines are being installed in embedded installations that are downstream of increasingly complicated inlet systems, such as those used in Unmanned Aerial Vehicles (UAVs). These inlet systems can produce complex swirl patterns in addition to total pressure distortion. The effect of swirl distortion on engine or compressor performance and operability must be evaluated. The gas turbine community is developing methodologies to measure and characterize swirl distortion. There is a strong need to develop a mechanism for generating a prescribed swirl distortion intensity and pattern. Several devices such as delta wings or complex turning vanes have been proposed and used to generate swirl distortion with limited success. Reference 1 presented by the authors described a versatile swirl distortion generator design that produced a wide range of swirl distortion patterns of a prescribed strength, including bulk swirl, 1/rev, and 2/rev patterns. However, some of the generated swirl patterns produced by this swirl generator system were not stable and tended to oscillate with time. Using advanced Computational Fluid Dynamic (CFD) techniques, significant improvements were made to the swirl generator design. Through CFD, the mechanisms behind swirl generation were better understood and a swirl generator system was designed and analyzed which produces much more stable and predictable swirl distortion patterns. This paper describes the design features of this improved swirl generator system and presents CFD results detailing the type of swirl patterns that can be produced. The flexibility and adaptability of the swirl generator system to produce a wide variety of swirl patterns and intensities are also highlighted.

scholarly journals INVESTIGATING NATURAL TREATMENT FACTORS AND INEQUALITIES OF MEDICINAL WATER INSTITUTIONS IN THE ASPECT OF TOURISM IN HUNGARY

2021 ◽  
Vol 36 (2spl) ◽  
pp. 555-562
Author(s):  
Ágnes Erzsébet HOJCSKA ◽  
◽  
Zoltán SZABÓ ◽  
Keyword(s):  
Medical Tourism ◽  
Secondary Data ◽  
Test Methods ◽  
Spatial Inequality ◽  
Data Set ◽  
Spatial Inequalities ◽  
Natural Treatment ◽  
Wide Range ◽  
Water Institutions ◽  
Medicinal Waters

The aim of the research is to reveal the spatial inequalities of the natural treatment factors in Hungary and the medicinal water institutions built on them, with the help of spatial research methods on the basis of secondary data. Due to the favorable geographical conditions of Central Europe, the Carpathian Basin has a considerable amount of natural resources. With the appreciation of health, in our days they represent significant value because they are becoming increasingly important in tourist services aimed at maintaining and restoring health. In Hungary, there are outstanding opportunities for this in health tourism, which provides a wide range of medical services, including medical tourism based on natural treatment factors. In order to achieve the set research goal, we used the range of the data set (range-ratio), the dispersion range (range), the relative range (relative range) and the dual measure (Éltető–Frigyes-index) as spatial inequality test methods for the geographically based examination of Hungary's natural treatment factors and the system of medicinal water institutions. The research results show that the spatial polarisation of natural treatment factors and the medicinal water institutions based on them show significant inequalities in Hungary. It has been proved that the development of the counties is outstanding in terms of medicinal waters and medicinal bath, and the spatial difference is also the lowest in the case of these treatment factors.

A Versatile Design of a Controlled Swirl Distortion Generator for Testing Gas Turbine Engines

2008 ◽  
Author(s):  
Yogi Sheoran ◽  
Bruce Bouldin
Keyword(s):  
Gas Turbine ◽  
Turbine Engines ◽  
Gas Turbine Engines ◽  
Delta Wings ◽  
Turbine Engine ◽  
System Sensitivity ◽  
Swirl Generator ◽  
Wide Range ◽  
Inlet Swirl ◽  
Area Of Concern

Inlet swirl distortion has recently become a major area of concern in the gas turbine engine community. Gas turbine engines are being installed in embedded installations that are downstream of increasingly complicated inlet systems, such as those used in Unmanned Aerial Vehicles (UAVs). These inlet systems can produce complex swirl patterns in addition to total pressure distortion. The effect of swirl distortion on engine or compressor performance and operability must be evaluated. The gas turbine community is developing methodologies to measure and characterize swirl distortion. There is a strong need to develop a mechanism for generating prescribed swirl distortion intensities and patterns for testing compression system sensitivity to swirl distortion. Several devices such as delta wings or complex turning vanes have been proposed and used to generate swirl distortion with limited success. This paper presents a versatile swirl distortion generator design that produces a wide range of swirl distortion patterns of a prescribed strength, including bulk swirl, 1/rev, and 2/rev patterns. It also creates different paired swirl patterns, varying from equal and opposite “twin swirls” to offset swirl pairs. This paper describes the design of the swirl generator. Computational Fluid Dynamics (CFD) results are presented along with some test data which illustrate how the swirl generator functions and how altering the swirl generator configuration can produce different swirl distortion patterns.

Structure Guided Molecular Docking Assisted Alignment Dependent 3DQSAR Study on Steroidal Aromatase Inhibitors (SAIs) as Anti-breast Cancer Agents

2019 ◽  
Vol 16 (7) ◽  
pp. 808-817 ◽  
Author(s):  
Laxmi Banjare ◽  
Sant Kumar Verma ◽  
Akhlesh Kumar Jain ◽  
Suresh Thareja
Keyword(s):  
Breast Cancer ◽  
Molecular Docking ◽  
Aromatase Inhibitors ◽  
Direct Synthesis ◽  
3D Qsar ◽  
Chemotherapeutic Agents ◽  
Modeling Tools ◽  
Data Set ◽  
Wide Range ◽  
Steroidal Aromatase Inhibitors

Background: In spite of the availability of various treatment approaches including surgery, radiotherapy, and hormonal therapy, the steroidal aromatase inhibitors (SAIs) play a significant role as chemotherapeutic agents for the treatment of estrogen-dependent breast cancer with the benefit of reduced risk of recurrence. However, due to greater toxicity and side effects associated with currently available anti-breast cancer agents, there is emergent requirement to develop target-specific AIs with safer anti-breast cancer profile. Methods: It is challenging task to design target-specific and less toxic SAIs, though the molecular modeling tools viz. molecular docking simulations and QSAR have been continuing for more than two decades for the fast and efficient designing of novel, selective, potent and safe molecules against various biological targets to fight the number of dreaded diseases/disorders. In order to design novel and selective SAIs, structure guided molecular docking assisted alignment dependent 3D-QSAR studies was performed on a data set comprises of 22 molecules bearing steroidal scaffold with wide range of aromatase inhibitory activity. Results: 3D-QSAR model developed using molecular weighted (MW) extent alignment approach showed good statistical quality and predictive ability when compared to model developed using moments of inertia (MI) alignment approach. Conclusion: The explored binding interactions and generated pharmacophoric features (steric and electrostatic) of steroidal molecules could be exploited for further design, direct synthesis and development of new potential safer SAIs, that can be effective to reduce the mortality and morbidity associated with breast cancer.

Integrative Data Analysis from a Unifying Research Synthesis Perspective

2018 ◽  
Author(s):  
Eun-Young Mun ◽  
Anne E. Ray
Keyword(s):  
Data Analysis ◽  
Large Scale ◽  
Research Synthesis ◽  
Alcohol Intervention ◽  
Data Set ◽  
Integrative Data Analysis ◽  
Level Data ◽  
Model Complex ◽  
Wide Range ◽  
Individual Participant

Integrative data analysis (IDA) is a promising new approach in psychological research and has been well received in the field of alcohol research. This chapter provides a larger unifying research synthesis framework for IDA. Major advantages of IDA of individual participant-level data include better and more flexible ways to examine subgroups, model complex relationships, deal with methodological and clinical heterogeneity, and examine infrequently occurring behaviors. However, between-study heterogeneity in measures, designs, and samples and systematic study-level missing data are significant barriers to IDA and, more broadly, to large-scale research synthesis. Based on the authors’ experience working on the Project INTEGRATE data set, which combined individual participant-level data from 24 independent college brief alcohol intervention studies, it is also recognized that IDA investigations require a wide range of expertise and considerable resources and that some minimum standards for reporting IDA studies may be needed to improve transparency and quality of evidence.

scholarly journals A Self-Spatial Adaptive Weighting Based U-Net for Image Segmentation

Electronics ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 348
Author(s):  
Choongsang Cho ◽  
Young Han Lee ◽  
Jongyoul Park ◽  
Sangkeun Lee
Keyword(s):  
Image Segmentation ◽  
Medical Image ◽  
Medical Image Segmentation ◽  
Feature Maps ◽  
Data Set ◽  
Feature Map ◽  
Adaptive Weighting ◽  
Spatially Adaptive ◽  
Wide Range ◽  
Decoder Architecture

Semantic image segmentation has a wide range of applications. When it comes to medical image segmentation, its accuracy is even more important than those of other areas because the performance gives useful information directly applicable to disease diagnosis, surgical planning, and history monitoring. The state-of-the-art models in medical image segmentation are variants of encoder-decoder architecture, which is called U-Net. To effectively reflect the spatial features in feature maps in encoder-decoder architecture, we propose a spatially adaptive weighting scheme for medical image segmentation. Specifically, the spatial feature is estimated from the feature maps, and the learned weighting parameters are obtained from the computed map, since segmentation results are predicted from the feature map through a convolutional layer. Especially in the proposed networks, the convolutional block for extracting the feature map is replaced with the widely used convolutional frameworks: VGG, ResNet, and Bottleneck Resent structures. In addition, a bilinear up-sampling method replaces the up-convolutional layer to increase the resolution of the feature map. For the performance evaluation of the proposed architecture, we used three data sets covering different medical imaging modalities. Experimental results show that the network with the proposed self-spatial adaptive weighting block based on the ResNet framework gave the highest IoU and DICE scores in the three tasks compared to other methods. In particular, the segmentation network combining the proposed self-spatially adaptive block and ResNet framework recorded the highest 3.01% and 2.89% improvements in IoU and DICE scores, respectively, in the Nerve data set. Therefore, we believe that the proposed scheme can be a useful tool for image segmentation tasks based on the encoder-decoder architecture.

scholarly journals Prediction of Wide Range Two-Dimensional Refractivity Using an IDW Interpolation Method from High-Altitude Refractivity Data of Multiple Meteorological Observatories

2021 ◽  
Vol 11 (4) ◽  
pp. 1431
Author(s):  
Sungsik Wang ◽  
Tae Heung Lim ◽  
Kyoungsoo Oh ◽  
Chulhun Seo ◽  
Hosung Choo
Keyword(s):  
High Altitude ◽  
Korean Peninsula ◽  
Interpolation Method ◽  
Atmospheric Condition ◽  
Propagation Path ◽  
Two Dimensional ◽  
Data Set ◽  
Wide Range ◽  
Atmospheric Data ◽  
Terrain Surface

This article proposes a method for the prediction of wide range two-dimensional refractivity for synthetic aperture radar (SAR) applications, using an inverse distance weighted (IDW) interpolation of high-altitude radio refractivity data from multiple meteorological observatories. The radio refractivity is extracted from an atmospheric data set of twenty meteorological observatories around the Korean Peninsula along a given altitude. Then, from the sparse refractive data, the two-dimensional regional radio refractivity of the entire Korean Peninsula is derived using the IDW interpolation, in consideration of the curvature of the Earth. The refractivities of the four seasons in 2019 are derived at the locations of seven meteorological observatories within the Korean Peninsula, using the refractivity data from the other nineteen observatories. The atmospheric refractivities on 15 February 2019 are then evaluated across the entire Korean Peninsula, using the atmospheric data collected from the twenty meteorological observatories. We found that the proposed IDW interpolation has the lowest average, the lowest average root-mean-square error (RMSE) of ∇M (gradient of M), and more continuous results than other methods. To compare the resulting IDW refractivity interpolation for airborne SAR applications, all the propagation path losses across Pohang and Heuksando are obtained using the standard atmospheric condition of ∇M = 118 and the observation-based interpolated atmospheric conditions on 15 February 2019. On the terrain surface ranging from 90 km to 190 km, the average path losses in the standard and derived conditions are 179.7 dB and 182.1 dB, respectively. Finally, based on the air-to-ground scenario in the SAR application, two-dimensional illuminated field intensities on the terrain surface are illustrated.

scholarly journals Focusing of Particles in a Microchannel with Laser Engraved Groove Arrays

Biosensors ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 263
Author(s):  
Tianlong Zhang ◽  
Yigang Shen ◽  
Ryota Kiya ◽  
Dian Anggraini ◽  
Tao Tang ◽  
...  
Keyword(s):  
Open Space ◽  
Lateral Displacement ◽  
Reynolds Numbers ◽  
Secondary Flows ◽  
Particle Sedimentation ◽  
Nanoparticle Separation ◽  
Wide Range ◽  
Fs Laser ◽  
Channel Bottom ◽  
Myoblast Cells

Continuous microfluidic focusing of particles, both synthetic and biological, is significant for a wide range of applications in industry, biology and biomedicine. In this study, we demonstrate the focusing of particles in a microchannel embedded with glass grooves engraved by femtosecond pulse (fs) laser. Results showed that the laser-engraved microstructures were capable of directing polystyrene particles and mouse myoblast cells (C2C12) towards the center of the microchannel at low Reynolds numbers (Re < 1). Numerical simulation revealed that localized side-to-center secondary flows induced by grooves at the channel bottom play an essential role in particle lateral displacement. Additionally, the focusing performance proved to be dependent on the angle of grooves and the middle open space between the grooves based on both experiments and simulation. Particle sedimentation rate was found to critically influence the focusing of particles of different sizes. Taking advantage of the size-dependent particle lateral displacement, selective focusing of micrometer particles was demonstrated. This study systematically investigated continuous particle focusing in a groove-embedded microchannel. We expect that this device will be used for further applications, such as cell sensing and nanoparticle separation in biological and biomedical areas.

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