scholarly journals Modelling and Validation of a Guided Acoustic Wave Temperature Monitoring System

Sensors ◽  
2021 ◽  
Vol 21 (21) ◽  
pp. 7390
Author(s):  
Lawrence Yule ◽  
Bahareh Zaghari ◽  
Nicholas Harris ◽  
Martyn Hill
Keyword(s):  
Monitoring System ◽  
Computer Modelling ◽  
Wave Mode ◽  
Test System ◽  
Guided Wave ◽  
Temperature Monitoring ◽  
The Future ◽  
Theoretical Predictions ◽  
Nozzle Guide ◽  
Nozzle Guide Vanes

The computer modelling of condition monitoring sensors can aide in their development, improve their performance, and allow for the analysis of sensor impact on component operation. This article details the development of a COMSOL model for a guided wave-based temperature monitoring system, with a view to using the technology in the future for the temperature monitoring of nozzle guide vanes, found in the hot section of aeroengines. The model is based on an experimental test system that acts as a method of validation for the model. Piezoelectric wedge transducers were used to excite the S0 Lamb wave mode in an aluminium plate, which was temperature controlled using a hot plate. Time of flight measurements were carried out in MATLAB and used to calculate group velocity. The results were compared to theoretical wave velocities extracted from dispersion curves. The assembly and validation of such a model can aide in the future development of guided wave based sensor systems, and the methods provided can act as a guide for building similar COMSOL models. The results show that the model is in good agreement with the experimental equivalent, which is also in line with theoretical predictions.

Characteristics of Volcanic Ash in a Gas Turbine Combustor and Nozzle Guide Vanes

2018 ◽  
Vol 140 (7) ◽  
Author(s):  
Lei-Yong Jiang ◽  
Yinghua Han ◽  
Prakash Patnaik
Keyword(s):  
Gas Turbine ◽  
Volcanic Ash ◽  
Inlet Temperature ◽  
Gas Turbine Combustor ◽  
Flow Passage ◽  
Guide Vanes ◽  
Cooling Flow ◽  
Cooling Passage ◽  
Nozzle Guide ◽  
Nozzle Guide Vanes

To understand the physics of volcanic ash impact on gas turbine hot-components and develop much-needed tools for engine design and fleet management, the behaviors of volcanic ash in a gas turbine combustor and nozzle guide vanes (NGV) have been numerically investigated. High-fidelity numerical models are generated, and volcanic ash sample, physical, and thermal properties are identified. A simple critical particle viscosity—critical wall temperature model is proposed and implemented in all simulations to account for ash particles bouncing off or sticking on metal walls. The results indicate that due to the particle inertia and combustor geometry, the volcanic ash concentration in the NGV cooling passage generally increases with ash size and density, and is less sensitive to inlet velocity. It can reach three times as high as that at the air inlet for the engine conditions and ash properties investigated. More importantly, a large number of the ash particles entering the NGV cooling chamber are trapped in the cooling flow passage for all four turbine inlet temperature conditions. This may reveal another volcanic ash damage mechanism originated from engine cooling flow passage. Finally, some suggestions are recommended for further research and development in this challenging field. To the best of our knowledge, it is the first study on detailed ash behaviors inside practical gas turbine hot-components in the open literature.

scholarly journals Assessing the Capacity of Adaptive Policy Pathways to Adapt on Time by Mapping Trigger Values to Their Outcomes

2019 ◽  
Vol 11 (6) ◽  
pp. 1716 ◽  
Author(s):  
Luciano Raso ◽  
Jan Kwakkel ◽  
Jos Timmermans
Keyword(s):  
Monitoring System ◽  
Decision Makers ◽  
Level Of Confidence ◽  
Adaptive Policy ◽  
Misclassification Errors ◽  
The Future ◽  
Adaptive Action ◽  
The Face

Climate change raises serious concerns for policymakers that want to ensure the success of long-term policies. To guarantee satisfactory decisions in the face of deep uncertainties, adaptive policy pathways might be used. Adaptive policy pathways are designed to take actions according to how the future will actually unfold. In adaptive pathways, a monitoring system collects the evidence required for activating the next adaptive action. This monitoring system is made of signposts and triggers. Signposts are indicators that track the performance of the pathway. When signposts reach pre-specified trigger values, the next action on the pathway is implemented. The effectiveness of the monitoring system is pivotal to the success of adaptive policy pathways, therefore the decision-makers would like to have sufficient confidence about the future capacity to adapt on time. “On time” means activating the next action on a pathway neither so early that it incurs unnecessary costs, nor so late that it incurs avoidable damages. In this paper, we show how mapping the relations between triggers and the probability of misclassification errors inform the level of confidence that a monitoring system for adaptive policy pathways can provide. Specifically, we present the “trigger-probability” mapping and the “trigger-consequences” mappings. The former mapping displays the interplay between trigger values for a given signpost and the level of confidence regarding whether change occurs and adaptation is needed. The latter mapping displays the interplay between trigger values for a given signpost and the consequences of misclassification errors for both adapting the policy or not. In a case study, we illustrate how these mappings can be used to test the effectiveness of a monitoring system, and how they can be integrated into the process of designing an adaptive policy.

scholarly journals Phase-delayed laser diode array allows ultrasonic guided wave mode selection and tuning

2013 ◽  
Vol 113 (14) ◽  
pp. 144904 ◽  
Author(s):  
Pasi Karppinen ◽  
Ari Salmi ◽  
Petro Moilanen ◽  
Timo Karppinen ◽  
Zuomin Zhao ◽  
...  
Keyword(s):  
Laser Diode ◽  
Mode Selection ◽  
Wave Mode ◽  
Guided Wave ◽  
Diode Array ◽  
Laser Diode Array ◽  
Ultrasonic Guided Wave

Forced responses on a radial turbine with nozzle guide vanes

2014 ◽  
Vol 23 (2) ◽  
pp. 138-144 ◽  
Author(s):  
Yixiong Liu ◽  
Ce Yang ◽  
Chaochen Ma ◽  
DaZhong Lao
Keyword(s):  
Guide Vanes ◽  
Radial Turbine ◽  
Nozzle Guide ◽  
Forced Responses ◽  
Nozzle Guide Vanes

Design of Temperature Monitoring System Based on MSP430

2011 ◽  
Vol 301-303 ◽  
pp. 1162-1165
Author(s):  
Fei Hu ◽  
Wen Qing Yin ◽  
Cai Rong Chen
Keyword(s):  
Monitoring System ◽  
Simple Structure ◽  
High Accuracy ◽  
Temperature Monitoring ◽  
Low Power Consumption ◽  
Key Factors ◽  
Process Data ◽  
Long Distance ◽  
Fast Acquisition ◽  
Digital Temperature Sensor

The Greenhouse Temperature Is one of the Key Factors for Controlling the Growth of Crops. Traditional Methods of Temperature Monitoring Can Not Meet the Modern Greenhouse Requirements of High Accuracy, Fast Acquisition and Response. a Greenhouse Temperature Monitoring System Based on MSP430 Was Designed. this System Uses Digital Temperature Sensor DS18B20 to Measure Temperature, MSP430 to Process Data and Transmit Data to the Host Computer through RS485 Bus, Realizing the Real-Time Detection and Long-Distance Transmission of Greenhouse Temperature. this System Has the Features of Simple Structure, Low Power Consumption, Stability and Strong Portability Etc.

A Radiofrequency Identification (RFID) Temperature-Monitoring System for Extended Maintenance of Nuclear Materials Packaging

2009 ◽  
Author(s):  
Kun Chen ◽  
Hanchung Tsai ◽  
Bud Fabian ◽  
Yung Liu ◽  
James Shuler
Keyword(s):  
Monitoring System ◽  
National Laboratory ◽  
Argonne National Laboratory ◽  
Text Message ◽  
Cost Savings ◽  
Nuclear Material ◽  
Temperature Monitoring ◽  
Department Of Energy ◽  
Application Software ◽  
Radiofrequency Identification

A temperature-monitoring system based on radiofrequency identification (RFID) has been developed for extending the maintenance period of the nuclear material packaging for storage and transportation. The system consists of tags, readers, and application software. The tag, equipped with a temperature sensor, is attached to the exterior of a package. The application software enables remote reading, via radio waves, of the temperature from the sensor in the tag. The system reports any temperature violations immediately via e-mail or text message, and/or posts the alarm on a secure website. The system can monitor thousands of packages and record individual temperature histories in a database. The first type of packaging that will benefit from the RFID technology is Model 9977, which has been certified by the U.S. Department of Energy (DOE) to ship and store fissile materials such as plutonium and uranium. The recorded data can be correlated to the temperature of the containment O-ring seals, based on the decay heat load of the contents. Accelerated aging studies of the Viton® GLT O-rings have shown that temperature is one of the key parameters governing the life of the O-ring seals, which maintain the integrity of the containment boundary of the package. Use of the RFID temperature-monitoring system to verify that the surface temperature remains below a certain threshold will make it possible to extend the leak-test period of the package from one year to up to five years. The longer leak-rate testing interval will yield a cost savings of up to $10,000 per package over five years. This work was conducted by Argonne National Laboratory in support of the DOE Packaging Certification Program, Office of Environmental Management, Office of Packaging and Transportation (EM-63).

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