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Highly enhanced pump power density inevitably results in a profound rise in pump temperature, which seriously influences both power loss and service performance. Heat loss analysis is an important part of analyzing the mechanical and cooling efficiency of a 2D piston pump. This paper focuses on heat loss analysis of this pump’s transmission. Firstly, theoretical and experimental studies are carried out on the thermal–hydraulic model to investigate the heat loss of the pump’s transmission. A pump test rig is developed and thermal experiments are conducted, from 1000 rpm to 6000 rpm. Furthermore, its transient thermal simulation model is implemented with Ansys software to capture the pump’s thermal status. The test convective heat transfer coefficients and temperature data are set in the model, and the simulation results are mutually validated with the experimental ones. Finally, the transmission’s heat loss is compared with its reference churning loss formula. The distribution of the transient heat loss is 49.66% into the end cap, 27.74% into the cylinder head, 13.30% into the inner cylinder, and 9.30% into the oil. The heat loss simulation results agree with the churning loss below 4000 rpm; therefore, the transmission thermal model is accurate and efficient.
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Willits, A. B. "HEAT TRANSMISSION AND TRANSMITTERS." Journal of the American Society for Naval Engineers 22, no. 1 (March 18, 2009): 139–44. http://dx.doi.org/10.1111/j.1559-3584.1910.tb04546.x.
Quintanilla, R., and B. Straughan. "Explosive instabilities in heat transmission." Proceedings of the Royal Society of London. Series A: Mathematical, Physical and Engineering Sciences 458, no. 2028 (December 8, 2002): 2833–37. http://dx.doi.org/10.1098/rspa.2002.1009.
Cathcart, W. L. "HEAT LOSSES IN STEAM TRANSMISSION." Journal of the American Society for Naval Engineers 27, no. 3 (March 18, 2009): 529–55. http://dx.doi.org/10.1111/j.1559-3584.1915.tb00539.x.
Marki, J., R. A. Pitts, T. Eich, A. Herrmann, J. Horacek, F. Sanchez, and G. Veres. "Sheath heat transmission factors on TCV." Journal of Nuclear Materials 363-365 (June 2007): 382–88. http://dx.doi.org/10.1016/j.jnucmat.2007.01.197.
Sultan, M. A., T. Z. Harmathy, and J. R. Mehaffey. "Heat transmission in fire test furnaces." Fire and Materials 10, no. 2 (June 1986): 47–55. http://dx.doi.org/10.1002/fam.810100202.
Tso, C. P., S. C. Yap, and K. S. Chan. "Heat transmission in cylindrical and spherical shells with exponential heat sources." Journal of Physics D: Applied Physics 23, no. 7 (July 14, 1990): 773–77. http://dx.doi.org/10.1088/0022-3727/23/7/004.
Durston, A. J. "THE TRANSMISSION OF HEAT THROUGH TUBE PLATES." Journal of the American Society for Naval Engineers 5, no. 2 (March 18, 2009): 436–64. http://dx.doi.org/10.1111/j.1559-3584.1893.tb04363.x.
Khroustalev, B. M., and V. D. Sizov. "DETERMINING HEAT TRANSMISSION RESISTANCE OF ENCLOSING STRUCTURES." ENERGETIKA. Proceedings of CIS higher education institutions and power engineering associations 61, no. 1 (January 23, 2018): 47–59. http://dx.doi.org/10.21122/1029-7448-2018-61-1-47-59.
Fulfillment of the activities aimed to an increase of the thermal resistance of enclosing structures requires the determination of their thermophysical characteristics with the use of the determination method based on the solution of problems of heat conduction, establishing the con- nection between the spatial and temporal temperature changes under the effect of heat source. This work uses the solution of the problem under nonstationary heating of the enclosing structure in the form of unrestricted plate with boundary conditions of the III kind. According to the known relations and graphs alterations in surface temperature depending on warm-up time, on thermal resistance of constructions and on arguments of Fo and Bi, i. e. initial and boundary conditions are determined. The graphic dependencies that have been obtained show that the surface temperature depends on the thermal resistance, while the temperature at the opposite surface during heat expo- sure remains practically unchanged during t = 5 h. Thus, if the outside air temperature is altered, then the rate of change of surface temperature or relative temperature q make it possible to deter- mine the thermophysical characteristics by solving the inverse problem of thermal conductivity with the use of the converted ratio to determine R as a function R = f(q, t). If the constructed graphic dependencies R = f(q, t) are used at different heat transfer coefficients, then according to the measured temperatures at different time intervals it is possible to determine thermal resistance in the same time intervals and, according to their average value, determine the required resistance to heat transfer R. The estimated ratio of analytical and graphic dependencies that we have obtained demonstrate the adequacy of the conducted full-scale measurements, if the areas with homogeneous temperature field and temperature history are chosen, and they can be used in determining the heat resistance of the enclosing structure in the form of unrestricted plate with boundary conditions of the III kind.
Etter, Christy L. "Numerical model of the transient behavior of a copper-water heat pipe." Thesis, Georgia Institute of Technology, 2000. http://hdl.handle.net/1853/19972.
The main portion of my thesis focuses on a 2-dimensional second order heat transmission problem in domains with pre-fractal interfaces. My focus is on the numerical approximation of the solutions. Precisely, I€™m concerned to develop a suitable mesh refinement algorithm that could be adapted to our situation, by taking into account the regularity of the solutions and the geometry of irregular pre-fractal interfaces. I obtain an error estimate between the weak solution and the discrete solution, which indicates an optimal rate of convergence as in the classical case when the solution has H^2-regularity. In addition, numerical simulations are also included, which demonstrates the features of our heat transmission model. Another portion of my thesis focuses on the asymptotic analysis of singular boundary value problems with highly conductive layers of pre-fractal type. My models illustrate the problems of a lower- dimensional highly conductive material intruding into a higher- dimensional material with lower conductivity. I consider a 2D model of Sierpinski pre-fractal layers and 3D models of hierarchical layers. The main results consist in the so-called Mosco-convergence of certain energy functionals, which implies the strong convergence of the solutions and of the spectral resolutions as a byproduct in real applications.
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Chu, Wun Wai. "Experimental study for the fully-developed single-phase heat transfer and friction factor in micro-fin tube." Thesis, University of Macau, 2011. http://umaclib3.umac.mo/record=b2493619.
Pidgeon, Wesley. "Numerical analysis of heat conduction from a buried heat pipe." Thesis, Georgia Institute of Technology, 1985. http://hdl.handle.net/1853/18393.
Norris, Pamela Marie. "An investigation of coolant passage heat transfer in a diesel engine cylinder head." Diss., Georgia Institute of Technology, 1992. http://hdl.handle.net/1853/17633.
With the advent of the new high Tc superconductors, liquid nitrogen will be one of the preferred cryogens used to cool these materials. Consequently, a more thorough understanding of the heat transfer characteristics of liquid nitrogen is required. In our investigations we examine the transient heating characteristics of liquid nitrogen to states of nucleate and film boiling under different liquid flow conditions. Using a platinum hot wire technique, it is verified that there is a premature transition to film boiling in the transient case at power levels significantly lower than under steady state nucleate boiling conditions. It is also shown that the premature transition can be reduced or eliminated depending on the flow velocity.
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Baird, James Robert. "Phase change heat transfer in narrow passages." Thesis, Graduate School of Engineering, 2001. http://hdl.handle.net/2123/5130.
Galarraga, Maider. "Heat balance of a historical church- transmission losses." Thesis, Högskolan i Gävle, Avdelningen för bygg- energi- och miljöteknik, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-17137.
The structure of old monumental churches differs a lot from contemporary buildings. The structural materials were wood, brick and stone. In order to construct high buildings with huge spans, thick massive walls and many massive columns were needed. Originally these buildings had no heating and for centuries the outdoor temperature determined the indoor climate. As churches are considered historical heritage buildings their renovation should be thoroughly studied. In this thesis the transmission losses of Hamrånge church will be analysed. Hence, the transmission trough walls and windows as well as the heat buffering of materials will be examined. In addition, the effect of possible reformation measurements will be concluded. Finally, this project belongs to a complete study of the church, were not only transmission losses are considered but also air infiltration losses and solar heat gain. That way, a comparison between them will be carried out in order to contribute to attain the objective of the project: possible restoration for church heating system with respect to preservation, energy requirements, thermal comfort and aesthetics. Church project
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Norris, Pamela Marie. "An experimental investigation of heat transfer in a diesel engine cylinder head." Thesis, Georgia Institute of Technology, 1989. http://hdl.handle.net/1853/17590.
Luzzini, Paolo, and Paolo Musolino. "Periodic Transmission Problems for the Heat Equation." In Integral Methods in Science and Engineering, 211–23. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-030-16077-7_17.
Blümel, J., I. Schmidt, W. Effenberger, H. Seitz, H. Willkommen, H. H. Brackmann, J. Löwer, and A. M. Eis-Hübinger. "Transmission of Parvovirus B19 by Heat-treated Coagulation Factor Concentrates." In 32nd Hemophilia Symposium Hamburg 2001, 149–54. Berlin, Heidelberg: Springer Berlin Heidelberg, 2003. http://dx.doi.org/10.1007/978-3-642-18150-4_21.
Pechanek, R., V. Kindl, and K. Hruska. "Air Gap Heat Transmission and Its Consideration in FEM Analyses." In Mechatronics 2013, 291–98. Cham: Springer International Publishing, 2014. http://dx.doi.org/10.1007/978-3-319-02294-9_37.
Mishuris, Gennady, Wiktoria Miszuris, and Andreas Öchsner. "Evaluation of Transmission Conditions for Thin Reactive Heat-Conducting Interphases." In Diffusion in Solids and Liquids III, 394–99. Stafa: Trans Tech Publications Ltd., 2008. http://dx.doi.org/10.4028/3-908451-51-5.394.
Mishuris, Gennady, Wiktoria Miszuris, and Andreas Öchsner. "Finite Element Verification of Transmission Conditions for 2D Heat Conduction Problems." In Materials Science Forum, 93–99. Stafa: Trans Tech Publications Ltd., 2007. http://dx.doi.org/10.4028/0-87849-438-3.93.
Chen, Hongqing, Chunfa Jiang, Yunfei Su, and Xiaowei Wang. "Temperature Distribution and Transmission in Multilayer Porous Asphalt Courses." In Lecture Notes in Civil Engineering, 321–29. Singapore: Springer Singapore, 2022. http://dx.doi.org/10.1007/978-981-19-1260-3_29.
AbstractThe objective of this paper was to investigate the temperature distribution and the law of temperature transmission in multilayer porous asphalt courses. Three types of multilayer porous asphalt courses are designed as the same thickness of actual pavements. In order to achieve this objective, experiments were conducted in an oven with different temperature, and samples were enwrapped with an efficient insulation material except the surface. The final temperature in samples is lower by 5~10 °C than ambient temperature and reduced gradually from top to bottom. The ability of heat transmission is related to the mixture’s air void and ambient temperature. The temperature transmission rate in porous asphalt mixture is lower than traditional dense graded asphalt mixture. At last, temperature transmission formulas of porous asphalt mixture are given.
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Öchsner, Andreas, and Wiktoria Miszuris. "Finite Element Verification of Transmission Conditions for Thin Reactive Heat-Conducting Interphases." In Diffusion in Solids and Liquids III, 400–405. Stafa: Trans Tech Publications Ltd., 2008. http://dx.doi.org/10.4028/3-908451-51-5.400.
Sun, Peng, Di Pang, Xuechun Qi, and Ningming Luo. "The Heat Treatment Deformation Law and the Improvement of Accuracy of the Transmission Gear." In Lecture Notes in Electrical Engineering, 647–61. Singapore: Springer Singapore, 2019. http://dx.doi.org/10.1007/978-981-13-9718-9_50.
Mishuris, Gennady, Wiktoria Miszuris, and Andreas Öchsner. "Evaluation of Transmission Conditions for a Thin Heat-Resistant Inhomogeneous Interphase in Dissimilar Material." In Materials Science Forum, 87–92. Stafa: Trans Tech Publications Ltd., 2007. http://dx.doi.org/10.4028/0-87849-438-3.87.
Тези доповідей конференцій з теми "Heat Transmission":
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Levorato, Marco, Nalini Venkatasubramanian, and Nikil Dutt. "Heat-aware transmission strategies." In 2015 Information Theory and Applications Workshop (ITA). IEEE, 2015. http://dx.doi.org/10.1109/ita.2015.7308981.
L, Natrayan. "Simulating laminar induced heat capacity and heat transmission convection using Al2O3 nanofluid." In International Conference on Mathematical and Statistical Physics, Computational Science, Education, and Communication (ICMSCE 2022), edited by Lazim Abdullah and Norma bt Alias. SPIE, 2023. http://dx.doi.org/10.1117/12.2675557.
Sato, Kimitoshi, Takushi Saito, Isao Satoh, and Yasuo Kurosaki. "Heat Transfer in Laser Transmission Welding of Thermoplastics Using Functional Pigment." In International Heat Transfer Conference 12. Connecticut: Begellhouse, 2002. http://dx.doi.org/10.1615/ihtc12.3550.
Tomo, Yoko, Alexandros Askounis, Khellil Sefiane, Yasuyuki Takata, and Koji Takahashi. "STUDY ON LIQUID-GAS INTERFACE AT NANOSCALE USING TRANSMISSION ELECTRON MICROSCOPY." In International Heat Transfer Conference 16. Connecticut: Begellhouse, 2018. http://dx.doi.org/10.1615/ihtc16.bae.023136.
Roth, Timothy, and Ann Anderson. "Liquid Crystal Thermography Using Light Transmission." In 9th AIAA/ASME Joint Thermophysics and Heat Transfer Conference. Reston, Virigina: American Institute of Aeronautics and Astronautics, 2006. http://dx.doi.org/10.2514/6.2006-3097.
Bravo, Richard J. "Inrush Current Behavior of Packaged Commercial Heat Pumps." In 2018 IEEE/PES Transmission and Distribution Conference and Exposition (T&D). IEEE, 2018. http://dx.doi.org/10.1109/tdc.2018.8440516.
Spinner, B., D. Stitou, and N. Mazet. "New Sorption Cycles for Heat and/or Cold Production Adapted for Long Distance Heat Transmission." In ASME 2002 International Mechanical Engineering Congress and Exposition. ASMEDC, 2002. http://dx.doi.org/10.1115/imece2002-33407.
The analysis of the combinations of dipoles, linked by a gas transfer between an endothermic element and an exothermal element, through an exothermal physical-chemical process in thermal contact with an other endothermic process, is the basis of a new process for the transmission at long distance of heat/cold production. The yield of such cycles is identified through the values of the unused exergy, the untapped exergy and the exergy which is produced in excess by the process.
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Nguyen, Minh Y., Yong T. Yoon, and Nack H. Choi. "Dynamic programming formulation of Micro-Grid operation with heat and electricity constraints." In 2009 Transmission & Distribution Conference & Exposition: Asia and Pacific. IEEE, 2009. http://dx.doi.org/10.1109/td-asia.2009.5356870.
Li, Kai-qin, Liang Du, and Wei-heng Han. "Icing Analysis of Transmission Lines Considering the Current Heat." In 2011 Asia-Pacific Power and Energy Engineering Conference (APPEEC). IEEE, 2011. http://dx.doi.org/10.1109/appeec.2011.5748707.
Ridouane, El Hassan, and Antonio Campo. "Model for the Heat Transmission in the Human Eye." In ASME 2005 International Mechanical Engineering Congress and Exposition. ASMEDC, 2005. http://dx.doi.org/10.1115/imece2005-80938.
Currently, most refractive surgery on the cornea is done by minimally invasive laser methods. Developing or improving new methods in laser medicine often is accompanied by theoretical modeling of the heat transmission in the human eye. The purpose of this study is to develop a mathematical model of the human eye based on the heat transfer equation. The intraocular temperature distribution is calculated using the finite volume method. The development of an accurate model of the human eye is difficult due to the lack of reliable biological data available on the constants and parameters that are used in the model. The different values for the parameters reported in the literature are employed in the model. The sensitivity of the temperature distribution to uncertainties in the parameters is investigated. The ambient temperature and blood flow rate lead to significant changes in the temperature in the anterior regions. In addition, remarkable effect is observed from the variation of the thermal conductivity of lens and blood temperature.
Звіти організацій з теми "Heat Transmission":
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Wu, Yu-Shu. A comparison of analytical approaches for wellbore heat transmission in layered formations. Office of Scientific and Technical Information (OSTI), August 1988. http://dx.doi.org/10.2172/6918217.
Unknown, Author. L51602 Criteria for Hot Tap Welding Further Studies. Chantilly, Virginia: Pipeline Research Council International, Inc. (PRCI), May 1989. http://dx.doi.org/10.55274/r0010102.
In the gas transmission industry there is a frequent need for modification of existing pipework. Modifications are made primarily by welding on additional pipes and branch connections to existing pipelines. The associated costs of shutting down a pipeline creates a situation whereby it becomes economically feasible to weld onto pipelines containing flowing, pressurized products. The risk of burn through and in particular, the susceptibility to cracking are greatly increased by the rapid cooling rates associated with the high heat sink effect of the flowing gas and in turn can result in excessive hardening of the heat affected zone in ferritic steels. Edison Welding Institute developed new criteria for safe hot tap welding procedures on all ferritic steels. Their approach is based on correlating field measurements of the ability of the pipe to conduct heat (i.e., its heat-sink capacity) to the cooling rate of the weld. Laboratory welding trials with simulated branch and sleeve connections on live pipelines containing natural gas were used to validate the new criteria. The results indicate that structurally sound hot tap repairs can be made with a high level of confidence.
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James, Christian, Ronald Dixon, Luke Talbot, Stephen James, Nicola Williams, and Bukola Onarinde. Assessing the impact of heat treatment on antimicrobial resistant (AMR) genes and their potential uptake by other ‘live’ bacteria. Food Standards Agency, August 2021. http://dx.doi.org/10.46756/sci.fsa.oxk434.
Addressing the public health threat posed by AMR is a national strategic priority for the UK, which has led to both a 20-year vision of AMR and a 5-year (2019 to 2024) AMR National Action Plan (NAP). The latter sets out actions to slow the development and spread of AMR with a focus on antimicrobials. The NAP used an integrated ‘One-Health’ approach which spanned people, animals, agriculture and the environment, and calls for activities to “identify and assess the sources, pathways, and exposure risks” of AMR. The FSA continues to contribute to delivery of the NAP in a number of ways, including through furthering our understanding of the role of the food chain and AMR.Thorough cooking of food kills vegetative bacterial cells including pathogens and is therefore a crucial step in reducing the risk of most forms of food poisoning. Currently, there is uncertainty around whether cooking food is sufficient to denature AMR genes and mobile genetic elements from these ‘dead’ bacteria to prevent uptake by ‘live’ bacteria in the human gut and other food environments - therefore potentially contributing to the overall transmission of AMR to humans. This work was carried out to assess these evidence gaps.
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Williams and Maxey. NR198803 Evaluation of an X80 Pipe Fabricated from a Plate Processed using On-line Accelerated Cooling. Chantilly, Virginia: Pipeline Research Council International, Inc. (PRCI), January 1988. http://dx.doi.org/10.55274/r0010186.
In recent years a number of important developments in steel making, rolling, and heat treatment have been applied to the production of plate for API Grades X65 through X80 line pipe. Based on industry interest in the performance of these steels in line pipe, a research task was to investigate the characteristics of representative examples of these new pipes. The objectives of this task are to provide independent measurements of pipe properties and to examine the metallurgical characteristics that may affect their performance in service. It is anticipated that information from the task will aid users in the selection of pipe for future gas-transmission lines. This report presents the results of an evaluation of an X80 pipe fabricated from a microalloyed, controlled-rolled steel processed using on-line accelerated cooling.
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Cola and Threadgill. L51548 Criteria for Hot Tap Welding. Chantilly, Virginia: Pipeline Research Council International, Inc. (PRCI), March 1988. http://dx.doi.org/10.55274/r0010128.
There is a frequent need in the transmission industry to modify pipe work by welding on additional pipes and branches to existing pipelines. It is very expensive to shut down the pipeline during this operation, and it is therefore, customary to make these welds onto live pipelines. This procedure must be done with great care, since a burn through would allow the leak of pressurized products. However, a greater problem is the rapid cooling of any weld due to the high heat sink effect of the flowing gas. In ferritic steel pipelines, this can lead to excessive hardening of the heat-affected zone (HAZ) of the weld and a high risk of cracking. Although guidelines are available to help welding engineers design safe welding procedures for hot tap welding, these guidelines were developed specifically for high carbon equivalent steels and are excessively conservative for the less hardenable lower carbon steels that have recently been supplied. This work develops a new criteria for hot tap welding which will allow safe procedures to be developed easily for all ferritic steels. The approach being used is primarily experimental and a series of tests using simulated branch and sleeve connections have been welded with various electrodes (E7018, E6010 and E8010) and cooling rates and the extent of cracking determined. A parallel study is being made to develop a technique in which the heat sink capacity of a pipeline containing flowing pressurized gas can be easily measured in the field. Knowledge of this parameter will enable the welding engineer to select an appropriate welding procedure.
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Begg, Darren. PR-214-124506-R02 Toughness and Strength of Sub-Arc Double Jointed High Strength Pipe. Chantilly, Virginia: Pipeline Research Council International, Inc. (PRCI), August 2017. http://dx.doi.org/10.55274/r0011418.
Current design of pipelines calls for overmatching weld metal tensile strength, forcing deformation to occur in the base material and not in the weld. If straining of the weld metal were to occur, higher levels of weld metal toughness would be required to prevent fracture initiation from pre-existing defects. There are three known issues related to the Submerged Arc Welding (SAW) double jointing of pipeline steels: - Consistently achieving weld metal strength and toughness requirements. - Heat affected zone (HAZ) softening of the base material. - Lack of an accepted test protocol for the entire range of pipe grades. The results herein will help improve the quality and efficiency of SAW welding in double jointing for all pipeline steels, and enhance industry's ability to complete double jointing and standardize its acceptance, and will improve construction efficiency, pipeline reliability and safety by addressing this important research gap in transmission pipeline welding.
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Threadgill, P. L., and M. J. Cola. L51601 Review of Procedures for Welding Onto Pressurized Pipelines. Chantilly, Virginia: Pipeline Research Council International, Inc. (PRCI), May 1989. http://dx.doi.org/10.55274/r0010279.
The welding of attachments onto pressurized pipelines and storage vessels (referred to as hot tapping) is a necessary and common operation in the transmission industry. Care must be exercised to choose a welding procedure that can reduce the risk of burn through and the formation of very high hardness levels in the heat-affected zone (HAZ) that can lead to a higher than normal risk of cracking. This report summarizes a state-of-the-art review of current procedures for hot tap welding on pressurized pipelines. All open literature related to hot tap welding were examined and catalogued, and areas requiring further research were identified. Although a large volume of literature exists on this subject, the majority gives accounts of successful repair work on specific items, rather than describing generalized safe procedures. The methods and controls vary widely; no national or industry standards exist.
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Taylor. L51755 Development and Testing of an Advanced Technology Vibration Transmission. Chantilly, Virginia: Pipeline Research Council International, Inc. (PRCI), July 1996. http://dx.doi.org/10.55274/r0010124.
Fiber optic sensors have been under development in industrial and government laboratories around the world for over a decade. The commercial market for fiber sensors for measuring parameters such as temperature, displacement, and liquid level is now estimated to exceed $100 M/year. Aside from the commercial interest, the U. S. Department of Defense has vigorously pursued the development of fiber gyroscopes and hydrophones. In spite of the high level of research and development activity, however, until recently fiber sensors had not been successfully applied in high-temperature engine environments. The goal of this effort is to develop and test high-temperature fiber optic sensors and show that they are suitable for monitoring vibration and other instabilities in gas turbine engines. The underlying technology developed during the course of PRCI projects PR- 219-9120 and PR-219-9225 during 1991-94 serves as the foundation for PR-240-9416. Transducers with the fiber optic Fabry-Perot interferometer (FFPI) configuration have been adapted for use in the turbomachinery environment.To ensure the survival of the FFPI sensors at high temperatures, two techniques for coating the fibers with metal have been developed: electroplating and vacuum deposition. Coated sensors have subsequently been embedded in aluminum and brass alloys. Experiments on a small Sargent Welch turbine engine have shown the high sensitivity of embedded FFPI strain sensors to vibration in rolling bearings. Data have been collected in both the time and frequency domain. A new accelerometer design in which a metal-coated fiber containing the FFPI element is soldered directly to a diaphragm in a stainless steel housing shows response similar to a piezoelectric accelerometer in shaker table tests. The high sensitivity of the FFPI accelerometer has been demonstrated in field tests in a Solar Centaur turbine engine, and the design has survived temperatures greater than 500�C in a test oven. A magnetometer with a physical configuration similar to that of the accelerometer has been used to measure the distance from the sensor head to a rotating shaft made of ferromagnetic material. This device, which functions as a proximity probe, has been used to monitor shaft rotation rate (keyphasor application) and as a shaft thrust position sensor. These results indicate the potential for performing critical measurements in turbine engines with FFPI sensors. They can measure acceleration, distance (proximity), strain (as it relates to bearing defect diagnosis), and gas pressure, and can operate at higher temperatures than conventional transducers.
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Clapham. L52206 3D Details of Defect-Induced MFL and Stress in Pipelines. Chantilly, Virginia: Pipeline Research Council International, Inc. (PRCI), December 2002. http://dx.doi.org/10.55274/r0011358.
The following report represents a continuation of our ongoing efforts to understand and quantify the effect of stress on MFL signals from oil and gas transmission line inspection tools. Earlier GRI funding has enabled us to develop an unprecedented understanding of stress effects on magnetic behaviour in pipeline steels, and this understanding is now further enhanced and applied to specific problems such as MFL signals from interacting defects and also MFL signals produced from mechanical damage. This report summarizes the result of the 2002 studies. These studies focused on 3 main areas: MFL signals from interacting defects � examined how magnetic behaviour is altered when two pits are sufficiently close that their stress and magnetization fields interact. This produces MFL signal effects that differ from those of isolated defects. MFL signal dependence on elastic, plastic and residual strain � this continues our fundamental investigation into stress effects. By combining applied uniaxial strain and stress-relief heat treatments, we have been able to show how magnetic behaviour and MFL signals respond to different types of deformation. Specifically, we have found the elastic deformation has a significant effect, but that plastic deformation does not. This is a fundamental result on which our further modeling and experimental studies are based. MFL signals from mechanical damage � this is the first year we have turned our attention to this specific area, however our earlier results have laid the groundwork for these studies. MFL signals from dents contain geometry and stress components. We have conducted experimental and finite element modeling studies of MFL signals from dented samples, and have shown that the MFL signal from shallow dents arises from the residual stress pattern, while severe dent signals are mainly related to dent geometry. This work forms the main part of a continuing study.
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Genetically informed family research, and anti-racism in mental health research - In Conversation with Dr. Yasmin Ahmadzadeh. ACAMH, August 2021. http://dx.doi.org/10.13056/acamh.16740.
We hear how Dr. Yasmin Ahmadzadeh helped to set up the Twins Early Development Study, CoTEDS, her research on genetically informed methods to examine the intergenerational transmission of psychopathology, advice for those considering a part-time PhD, and anti-racism in mental health research.
