An Off-Resonance Synchronous Vibration Based Method for Rotor System Damage Detections

2005 ◽  
Author(s):  
Huageng Luo ◽  
Hector Rodriguez ◽  
Darren Hallman ◽  
Dennis Corbly
Keyword(s):  
Final Section ◽  
State Of The Art ◽  
Detection System ◽  
Detection Algorithm ◽  
Integrated System ◽  
Test Results ◽  
Test Rig ◽  
Test Setup ◽  
First Order ◽  
Vibration Detection

This paper presents a methodology of detecting rotor imbalances, such as mass imbalance and crack-induced imbalance, using shaft synchronous vibrations. A vibration detection algorithm is derived based on the first order nonresonant synchronous vibration response. A detection system is integrated by using state-of-the-art commercial analysis equipment. A laboratory rotor test rig with controlled mass imbalances was used to verify the integrated system. The system is then deployed to an engine sub-assembly test setup. Four specimens were used in the subassembly test and the test results are reported in the final section.

Introduction and Commissioning of the New Darmstadt Transonic Compressor Test Facility

2019 ◽  
Author(s):  
Christian Kunkel ◽  
Jan Werner ◽  
Daniel Franke ◽  
Heinz-Peter Schiffer ◽  
Fabian Wartzek ◽  
...  
Keyword(s):  
Control Systems ◽  
Gas Turbines ◽  
State Of The Art ◽  
Test Facility ◽  
Test Results ◽  
Test Rig ◽  
Vast Number ◽  
Transonic Compressor ◽  
Profound Knowledge ◽  
And Control

Abstract With the well-known Transonic Compressor Darmstadt (TCD) in operation since 1994, profound knowledge in designing and operating a sophisticated test-rig is available at the Institute of Gas Turbines and Aerospace Propulsion of TU Darmstadt. During this period, TCD has been subject to a vast number of redesigns within different measurement campaigns (see [1], [2], [3], [4], [5], [6], [7], [8]). To expand the capabilities and ensure a sustainable process of compressor research, a new test facility was designed and built by the institute. The new test rig Transonic Compressor Darmstadt 2 (TCD2) features increased power for higher pressure ratios and higher mass-flow, a state of the art control system, increased flexibility towards different compressor geometries and modern data acquisition hardware and software. Following the successful commissioning of the test-rig in March 2018, a first measurement campaign has been conducted. Early test results regarding aerodynamic performance and aeroelastic effects of the test compressor are presented together with a detailed overview of test-rig infrastructure and control systems as well as the test compressor and the measurement hardware.

scholarly journals High Temperature, Permanent Magnet Biased, Fault Tolerant, Homopolar Magnetic Bearing Development

2008 ◽  
Author(s):  
Alan Palazzolo ◽  
Randall Tucker ◽  
Andrew Kenny ◽  
Kyung-Dae Kang ◽  
Varun Ghandi ◽  
...  
Keyword(s):  
High Temperature ◽  
Design Methodology ◽  
Permanent Magnets ◽  
Fault Tolerant ◽  
State Of The Art ◽  
Magnetic Bearing ◽  
Test Results ◽  
Test Rig ◽  
Control Forces ◽  
Good Agreement

This paper summarizes the development of a magnetic bearing designed to operate at 1,000F. A novel feature of this high temperature magnetic bearing is its homopolar construction which incorporates state of the art high temperature, 1,000F, permanent magnets. A second feature is its fault tolerance capability which provides the desired control forces with over one-half of the coils failed. The construction and design methodology of the bearing is outlined and test results are shown. The agreement between a 3D finite element, magnetic field based prediction for force is shown to be in good agreement with predictions at room and high temperature. A 5 axis test rig will be complete soon to provide a means to test the magnetic bearings at high temperature and speed.

The Study of Vibration Diagnosis Method for GIS

2013 ◽  
Vol 295-298 ◽  
pp. 2429-2432
Author(s):  
Pei Ding ◽  
Zhen Hua Yan ◽  
Fei Yue Ma ◽  
Liang Zhang ◽  
Jun Hao Li ◽  
...  
Keyword(s):  
Fault Diagnosis ◽  
Field Test ◽  
Detection Method ◽  
Detection System ◽  
Vibration Signal ◽  
Normal Operation ◽  
Vibration Test ◽  
Test Results ◽  
Vibration Detection ◽  
Diagnosis Method

Gas insulated switchgear (GIS) will generate vibration during normal operation for the electromagnetic force. There will be generate abnormal vibration when the contacts are undesirable, the guide rod stressed unevenness. Therefore, it can be effective in fault diagnosis of this machineries through the vibration test of GIS in field. The vibration detection method of GIS equipment in field is studied in this paper, the composition of the vibration detection system is described. The field test has been done using vibration detection system and the test results show that through the vibration signal detected from the GIS equipment, the vibration characteristics of GIS can be clarified and make the fault diagnosis effectively.

scholarly journals Low-Cost Multisensor Integrated System for Online Walking Gait Detection

2021 ◽  
Vol 2021 ◽  
pp. 1-15
Author(s):  
Lingyun Yan ◽  
Guowu Wei ◽  
Zheqi Hu ◽  
Haohua Xiu ◽  
Yuyang Wei ◽  
...  
Keyword(s):  
Detection System ◽  
Low Cost ◽  
Detection Algorithm ◽  
High Accuracy ◽  
Integrated System ◽  
Heel Strike ◽  
Detection Accuracy ◽  
Time Error ◽  
Kinematic Data ◽  
Compact Size

A three-dimensional motion capture system is a useful tool for analysing gait patterns during walking or exercising, and it is frequently applied in biomechanical studies. However, most of them are expensive. This study designs a low-cost gait detection system with high accuracy and reliability that is an alternative method/equipment in the gait detection field to the most widely used commercial system, the virtual user concept (Vicon) system. The proposed system integrates mass-produced low-cost sensors/chips in a compact size to collect kinematic data. Furthermore, an x86 mini personal computer (PC) running at 100 Hz classifies motion data in real-time. To guarantee gait detection accuracy, the embedded gait detection algorithm adopts a multilayer perceptron (MLP) model and a rule-based calibration filter to classify kinematic data into five distinct gait events: heel-strike, foot-flat, heel-off, toe-off, and initial-swing. To evaluate performance, volunteers are requested to walk on the treadmill at a regular walking speed of 4.2 km/h while kinematic data are recorded by a low-cost system and a Vicon system simultaneously. The gait detection accuracy and relative time error are estimated by comparing the classified gait events in the study with the Vicon system as a reference. The results show that the proposed system obtains a high accuracy of 99.66% with a smaller time error (32 ms), demonstrating that it performs similarly to the Vicon system in the gait detection field.

Comparative Study of a Felt Abradable Seal

2018 ◽  
Author(s):  
Dan Hasnedl ◽  
Premysl Epikaridis
Keyword(s):  
State Of The Art ◽  
Analytical Formula ◽  
Operating Conditions ◽  
Test Method ◽  
Experimental Comparison ◽  
Maximum Efficiency ◽  
Test Results ◽  
Test Rig ◽  
New Type ◽  
Efficiency Gap

In turbo-machinery, abradable layers are used to protect sensible components while keeping minimal possible clearances for maximum efficiency. This article describes the experimental comparison of state of the art abradable layers used as steam turbine seals and a new type of abradable layer made of a metallic felt. The comparison is done via abradability and leakage testing. The leakage is also compared to a state of the art analytical formula to show the effect on the thermal cycle calculation. An abradable test rig is presented together with the test method. Test results show the value of the Felt seal compared to other two types at low contact speed area. A steam test rig is also presented. Seal leakage at real operating conditions is evaluated and compared to an analytical formula. The leakage results show some efficiency gap compared to other two types of seals.

scholarly journals Improving real-time drone detection for counter-drone systems

2021 ◽  
pp. 1-26
Author(s):  
E. Çetin ◽  
C. Barrado ◽  
E. Pastor
Keyword(s):  
Object Detection ◽  
Real Time ◽  
State Of The Art ◽  
Low Cost ◽  
Detection Algorithm ◽  
Test Results ◽  
Security Risks ◽  
Art Object ◽  
The Cost

Abstract The number of unmanned aerial vehicles (UAVs, also known as drones) has increased dramatically in the airspace worldwide for tasks such as surveillance, reconnaissance, shipping and delivery. However, a small number of them, acting maliciously, can raise many security risks. Recent Artificial Intelligence (AI) capabilities for object detection can be very useful for the identification and classification of drones flying in the airspace and, in particular, are a good solution against malicious drones. A number of counter-drone solutions are being developed, but the cost of drone detection ground systems can also be very high, depending on the number of sensors deployed and powerful fusion algorithms. We propose a low-cost counter-drone solution composed uniquely by a guard-drone that should be able to detect, locate and eliminate any malicious drone. In this paper, a state-of-the-art object detection algorithm is used to train the system to detect drones. Three existing object detection models are improved by transfer learning and tested for real-time drone detection. Training is done with a new dataset of drone images, constructed automatically from a very realistic flight simulator. While flying, the guard-drone captures random images of the area, while at the same time, a malicious drone is flying too. The drone images are auto-labelled using the location and attitude information available in the simulator for both drones. The world coordinates for the malicious drone position must then be projected into image pixel coordinates. The training and test results show a minimum accuracy improvement of 22% with respect to state-of-the-art object detection models, representing promising results that enable a step towards the construction of a fully autonomous counter-drone system.

Photocatalytic Discolouration of Solutions of Reactive Dyes in the Presence of H2O2

1995 ◽  
Vol 30 (1) ◽  
pp. 53-60 ◽  
Author(s):  
Deng Nansheng ◽  
Tian Shizhong ◽  
Xia Mei
Keyword(s):  
Photochemical Reaction ◽  
Uv Light ◽  
Reactive Dyes ◽  
Solar Light ◽  
Rate Equations ◽  
Oh Radical ◽  
Test Results ◽  
Dye Molecules ◽  
First Order ◽  
Dye Solutions

Abstract Tests for the photocatalytic degradation of solutions of three reactive dyes, Red M-5B, Procion Blue MX-R and Procion Black H-N, in the presence of H2O2 were carried out. When the solutions of the three reactive dyes were irradiated by UV or solar light, the colour of the solutions disappeared gradually. A statistical analysis of the test results indicated a linear relation between the concentration of dyes and the time of irradiation. The discolouration reaction of the solutions was of the first order. Rate equations for the discolouration reactions of dye solutions were developed. The dark reactions or the dye solutions containing H2O2 were very slow, illustrating that the photochemical reaction played a very important role. It was demonstrated that UV light and solar light (300 to 380 nm) photolyzes the HO and that the resulting OH radical reacts with the dye molecules and destroys the chromophore.

Experiences in Field Testing a Variety of Aeration Equipment in Sweden and in the U.S.A. by Offgas Analysis

1989 ◽  
Vol 21 (10-11) ◽  
pp. 1421-1429
Author(s):  
D. T. Redmon ◽  
W. C. Boyle ◽  
B. G. Hellstrom
Keyword(s):  
Oxygen Transfer ◽  
State Of The Art ◽  
Field Testing ◽  
Analysis Procedure ◽  
Test Results ◽  
Transfer Testing ◽  
Parallel Tests

The background and theory of the offgas analysis procedure used in oxygen transfer testing of diffused aeration tanks is reviewed. Correlation of this method with other applicable procedures in parallel tests is reported. State-of-the-art equipment and accessories are described. Advantages of the procedure are identified, as are precautionary considerations regarding its use. Applications considered appropriate for its employment are delineated. Experience and test results in both Sweden and the U.S.A. on a variety of aeration devices are disclosed.

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