Towards a practical Johnson noise thermometer for long-term measurements in harsh environments

Existing temperature sensors such as thermocouples and platinum resistance thermometers suffer from calibration drift, especially in harsh environments, due to mechanical and chemical changes (and transmutation in the case of nuclear applications). A solution to the drift problem is to use temperature sensors based on fundamental thermometry (primary thermometers) where the measured property is related to absolute temperature by a fundamental physical law. A Johnson noise thermometer is such a sensor and uses the measurement of the extremely small thermal voltage noise signals generated by any resistive element to determine temperature using the Johnson-Nyquist equation. A Johnson noise thermometer never needs calibration and is insensitive to the condition of the sensor material, which makes it ideally suited to long-term temperature measurement in harsh environments. These can include reactor coolant circuits, in-pile measurements, nuclear waste management and storage, and severe accident monitoring. There have been a number of previous attempts to develop a Johnson noise thermometer for the nuclear industry, but none have achieved commercialization because of technical difficulties. We describe the results of a collaboration between the National Physical Laboratory and Metrosol Limited, which has led to a new technique for measuring Johnson noise that overcomes the previous problems that have prevented commercialization. The results from a proof-of-principle prototype that demonstrates performance commensurate with the needs of nuclear applications is presented, together with details of progress towards the commercialization of the technology. The development partners have effected a step change in the application of primary thermometry to industrial applications and seek partners for field trials and further exploitation.

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Evaluation for long-term structural shading materials for use in harsh environments

Journal of Applied Mechanical Engineering ◽

10.4172/2168-9873-c1-013 ◽

2017 ◽

Vol 06 (06) ◽

Author(s):

Omar S Es-Said

Keyword(s):

Harsh Environments

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Vehicle Pose Estimation and SONAR Sensor Based Mapping

Volume 4A: Dynamics, Vibration, and Control ◽

10.1115/imece2015-52427 ◽

2015 ◽

Author(s):

Hesham Ismail ◽

Balakumar Balachandran

Keyword(s):

Feature Extraction ◽

Pose Estimation ◽

Harsh Environments ◽

Storage Tanks ◽

Sonar Sensors ◽

Oil Storage ◽

Mobile Vehicle ◽

Localization And Mapping ◽

Sonar Sensor

In carrying out simultaneous localization and mapping, a mobile vehicle is used to simultaneously estimate its position and build a map of the environment. The long-term goal of this work is to build an autonomous inspection mobile vehicle for oil storage tanks and pipelines. The harsh environmental conditions in storage tanks and pipelines limit the types of feature extraction sensors and vehicle pose estimation sensors that one can use. Here, a SOund Navigation And Ranging (SONAR) sensor will be used for feature extraction, and a gyroscope and an encoder will be used for vehicle pose estimation. The integration of these sensors (SONAR, encoder, and gyroscope) will be discussed in this paper, along with the use of a recently developed algorithm fusion for SONAR sensors. The integration of the sensors represents a step towards implementation of concurrent localization and mapping progress in harsh environments.

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A Parametric Study for the Design of Steel Catenary Riser System in Deepwater Harsh Environments

Volume 3: Pipeline and Riser Technology; Ocean Space Utilization ◽

10.1115/omae2008-57179 ◽

2008 ◽

Cited By ~ 2

Author(s):

Jie Xia ◽

Purnendu K. Das ◽

Daniel Karunakaran

Keyword(s):

Parametric Study ◽

Computer Time ◽

Harsh Environments ◽

Analysis Tool ◽

Primary Analysis ◽

Steel Catenary Riser ◽

Analysis Process ◽

Steel Catenary Risers ◽

Northern North Sea

In recent years, offshore reservoirs have been developed in deeper and deeper water environments, where floating production, storage and offloading (FPSO), semi-submersibles, spars and TLPs are considered to be the most economically viable platforms. Steel catenary risers (SCRs) are being considered for these production units in deepwater development such as Northern North Sea. A variety of uncertainties are associated with material behaviour, environmental loading, hydromechanics modelling, structural modelling, and fatigue / corrosion / wear characteristics, especially around hang-off and touch down areas. SCRs used in conjunction with a semi-submersible or a FPSO in deepwater harsh environments present significant design challenges. The large vertical motions at the FPSO or semi induce severe riser response, which results in difficulty meeting strength and fatigue criteria at the hang-off and touch down point locations. To improve the understanding of SCR behaviour and increase the confidence in the design of such systems in deepwater harsh environments, a parametric study was carried out in this paper to deal with the factors that mainly influence the loading condition and fatigue life of the riser. Two cases, one steel catenary riser connected to a semi-submersible and one steel catenary riser connected to a FPSO, were studied and compared. And weight-optimized configurations were applied for both risers. Riflex combined with DeepC was the primary analysis tool used for the long-term response of the nonlinear structure SCR’s simulations, which is high computer time consuming. Hence, the parameters affecting the efficiency and accuracy of the simulations have also been studied during the analysis process.

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Reduced non-linearities and improved temperature measurements for the NIST Johnson noise thermometer

Metrologia ◽

10.1088/0026-1394/46/5/016 ◽

2009 ◽

Vol 46 (5) ◽

pp. 512-524 ◽

Cited By ~ 19

Author(s):

Jifeng Qu ◽

S P Benz ◽

H Rogalla ◽

D R White

Keyword(s):

Temperature Measurements ◽

Johnson Noise ◽

Noise Thermometer

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Special Issue: “Coatings for Harsh Environments”

Coatings ◽

10.3390/coatings10040407 ◽

2020 ◽

Vol 10 (4) ◽

pp. 407

Author(s):

Shiladitya Paul

Keyword(s):

Protective Coatings ◽

Composite Coatings ◽

Harsh Environments ◽

Process Equipment ◽

Special Issue ◽

The World ◽

Critical Components ◽

Long Term Performance ◽

Term Performance

The operation of numerous safety-critical components in industries around the world relies on protective coatings. These coatings often allow process equipment to be purposeful in environments well beyond the operational limit of the uncoated components. Durability, ease of application, repairability, reliability and long-term performance of such coatings are vital to their application. Therefore, this Special Issue of Coatings, “Coatings for Harsh Environments”, is devoted to research and review articles on the metallic, non-metallic and composite coatings used in aggressive environments.

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