Thermal Profiling of Automotive Turbochargers in Durability Tests

2021 ◽  
Author(s):  
Christopher Pilgrim ◽  
Jan Ehrhard ◽  
Mario Schinnerl ◽  
Silvia Araguás Rodríguez ◽  
David Peral ◽  
...  
Keyword(s):  
Maximum Temperature ◽  
Durability Test ◽  
Measurement Capability ◽  
Powertrain System ◽  
Cyclic Operation ◽  
Thermal Profiling ◽  
Durability Testing ◽  
Critical Components ◽  
First Time ◽  
Spatial Temperature

Abstract A major portion of the development of an automotive powertrain system is devoted to robustness and durability testing to ascertain the viability of the design. For turbochargers, thermo-mechanical fatigue is often considered as life limiting failure mechanism for the turbine section, therefore, these tests involve repeated and continuous cycling of the turbocharger for hundreds of hours. The Thermal History Coatings (THC) can offer a new and unique solution. THCs are applied to the surface of a component and, when heated, the coating permanently changes according to the maximum temperature of exposure. The technique has been used in several turbomachinery, and other applications to capture the spatial temperature distribution of critical components. However, the turbocharger durability test presents new challenges for the technique. It has not been tested in this type of application and repeated cycling operation can test the response of the coating on the temperature measurements. In this paper, the capability of the THC for this application was investigated. For the first time, the effect of cyclic operation on the THC is reported. The measurement capability was demonstrated on two turbine housings tested on a gas stand, one for a single cycle, another for 10 cycles. The results show that the surface temperature profile of the two turbine housings can be accurately recorded and the results are validated against the installed thermocouples. The demonstration indicates that the THC can be used to acquire accurate and detailed spatial temperature distributions. This information improves the interpretation of a durability test.

Thermal Profiling of Automotive Turbochargers in Durability Tests

2020 ◽  
Author(s):  
Christopher C. Pilgrim ◽  
Jan Ehrhard ◽  
Mario Schinnerl ◽  
Silvia Araguás-Rodríguez ◽  
David Peral ◽  
...  
Keyword(s):  
Temperature Profile ◽  
Combustion Process ◽  
Temperature Data ◽  
Maximum Temperature ◽  
Durability Test ◽  
Measurement Capability ◽  
Product Release ◽  
Internal Surfaces ◽  
Thermal Profiling ◽  
Spatial Temperature

Abstract A major portion of the development of an automotive powertrain system is devoted to robustness and durability testing to ascertain the viability of the design. For turbochargers, thermo-mechanical fatigue is often considered as life limiting failure mechanism for the turbine section, therefore, these tests involve repeated and continuous cycling of the turbocharger for hundreds of hours. Thermocouples are used to monitor the temperature during the test, however, they only provide information at the location to which they are attached, are practically challenging to apply to all areas of interest and are prone to fail due to the thermal cycling throughout the test. As a result, there may be very limited temperature data at the end of the test. If a failure occurred in the system during the testing, the lack of temperature data can inhibit the understanding of the cause. Further testing may be required and delay product release, which add significant expense to the product development. The Thermal History Coatings (THC) developed by Sensor Coating Systems can offer a new and unique solution to provide complimentary temperature information for this purpose. THCs are applied to the surface of a component and, when heated, the coating permanently changes according to the maximum temperature of exposure. A laser-based instrumentation system is then used to measure the coating or paint, and through calibration, the maximum temperature profile of the surface can be recorded. Although this technique is relatively new, it has been used in several turbomachinery, and other applications to capture the spatial temperature distribution of critical components. However, the turbocharger durability test presents new challenges for the technique. It has not been tested in this type of application and the extended and repeated cycling operation can test the durability of the coating and will influence the response of the coating, hence, the temperature measurements. The internal surfaces of the turbocharger will also be exposed to the exhaust gases of the combustion process. In this paper, the capability of the THC for this application was investigated. For the first time, the effect of cyclic operation on the THC is reported. The measurement capability was demonstrated on two turbine housings tested on a gas stand, one for a single cycle, another for 10 cycles. The results show that the surface temperature profile of the two turbine housings can be accurately recorded and the results are validated against the installed thermocouples. The demonstration indicates that the THC can be used to acquire accurate and detailed spatial temperature distributions, which significantly enhance the information from thermocouples alone. This information can be used to improve the interpretation of the durability test and hence accelerate new product release.

scholarly journals Bearing Severity Fault Evaluation Using Contour Maps—Case Study

2021 ◽  
Vol 11 (14) ◽  
pp. 6452
Author(s):  
César Ricardo Soto-Ocampo ◽  
Juan David Cano-Moreno ◽  
José Manuel Mera ◽  
Joaquín Maroto
Keyword(s):  
Health Indicators ◽  
Bearing Faults ◽  
Contour Maps ◽  
Initial Stage ◽  
Critical Components ◽  
Bearing Damage ◽  
First Time ◽  
Current Operating

Increasing industrial competitiveness has led to an increased global interest in condition monitoring. In this sector, rotating machinery plays an important role, where the bearing is one of the most critical components. Many vibration-based signal treatments are already being used to identify features associated with bearing faults. The information embedded in such features are employed in the construction of health indicators, which allow for evaluation of the current operating status of the machine. In this work, the use of contour maps to represent the diagnosis map of a bearing, used as a health map, is presented for the first time. The results show that the proposed method is promising, allowing for the satisfactory detection and evaluation of the severity of bearing damage. In this initial stage of the research, our results suggest that this method can improve the classification of bearing faults and, therefore, optimise maintenance processes.

scholarly journals Seaweed resources of the Hawaiian Islands

2019 ◽  
Vol 62 (5) ◽  
pp. 443-462
Author(s):  
Karla J. McDermid ◽  
Keelee J. Martin ◽  
Maria C. Haws
Keyword(s):  
Marine Ecosystem ◽  
Hawaiian Islands ◽  
Algal Species ◽  
Cultural Knowledge ◽  
Native Populations ◽  
Critical Components ◽  
Many Sources ◽  
Marine Flora ◽  
First Time ◽  
Collaborative Efforts

Abstract Up-to-date information about the unique marine flora of the Hawaiian Islands – its environment, uses, cultivation, conservation, and threats – comes from many sources, and is compiled here for the first time. The seaweed resources of the Hawaiian Islands are taxonomically diverse, biogeographically intriguing, ecologically complex, culturally significant, and economically valuable. Macroalgae, historically and today, are critical components of the marine ecosystem, as well as the diet and culture of people living in the islands. Some Hawaiian seaweeds are known to contain valuable bioactive compounds that have potential medical and pharmaceutical applications. Cultivation of Hawaiian seaweeds is carried out in tanks, ponds, and along the shoreline, both commercially and by “back-yard” farmers. Several community groups are actively working to preserve cultural knowledge, to re-plant the reefs, and to remove invasive algal species. The seaweed resources of Hawaiʻi are cherished, but are at risk. The future of seaweed cultivation, maintenance and revitalization of native populations, and preservation of cultural knowledge relies on the collaborative efforts of all stakeholders.

Research on Environmental Durability Testing System for Automobile Engine ECU

2011 ◽  
Vol 121-126 ◽  
pp. 2855-2859 ◽  
Author(s):  
Miao Yu ◽  
Lu Shuai ◽  
Jiang Wei Guo ◽  
Jie Fu
Keyword(s):  
Testing System ◽  
Time To Failure ◽  
Durability Test ◽  
Automobile Engine ◽  
Management Software ◽  
Sensor Signals ◽  
Durability Testing ◽  
Environmental Durability ◽  
Testing Management ◽  
Set Up

Based on the principle and specifications of Environmental Durability Test on automobile engine ECU, an open, intelligent and practical ECU durability testing system (EDTS) is designed. The system consisted of a simulation platform and a testing management software. The platform provided stimulating sensor signals and simulation loads, and an online automotive environment was built. The management software sent various instructions to set up the platform and read the ECU running status data. And this EDTS has been applied to test a kind of domestic automobile engine ECU．The experimental results shows that the mean time to failure (MTTF) of ECU samples was improved and the testing period was shortened greatly.

scholarly journals Distortion Optimization of Engine Cylinder Liner Using Spectrum Characterization and Parametric Analysis

2016 ◽  
Vol 2016 ◽  
pp. 1-11 ◽  
Author(s):  
Zhaohui Yang ◽  
Baotong Li ◽  
Tianxiang Yu
Keyword(s):  
Spectrum Analysis ◽  
Parametric Analysis ◽  
Cylinder Liner ◽  
Engine Operation ◽  
Practical Procedure ◽  
Operation Conditions ◽  
Powertrain System ◽  
Optimization Simulation ◽  
Structural Configurations ◽  
Critical Components

In an automotive powertrain system, the cylinder liner is one of the most critical components which possesses the intricate structural configurations coupled with complex pattern of various operational loads. This paper attempts to develop a concrete and practical procedure for the optimization of cylinder liner distortion for achieving future requirements regarding exhaust emissions, fuel economy, and oil consumptions. First, numerical calculation based on finite element method (FEM) and computational fluid dynamics (CFD) is performed to capture the mechanism of cylinder liner distortion under actual engine operation conditions. Then, a spectrum analysis approach is developed to describe the distribution characteristic of operational loads (thermal and mechanical) around the circumference of a distorted cylinder bore profile; the FFT procedure provides an efficient way to implement this calculation. With this approach, a relationship between the dominant order of distortion and special operational load is obtained; the design features which are critically relative to cylinder liner distortion are also identified through spectrum analysis. After characterizing the variation tendency of each dominant order of distortion through parametric analysis, a new design scheme is established to implement the distortion optimization. Simulation results indicate that a much better solution is obtained by using the proposed scheme.

scholarly journals Development of Vibration Loading Profiles for Accelerated Durability Tests of Ground Vehicles

2011 ◽  
Author(s):  
Ke Xu ◽  
Yan Wu ◽  
Qiong Wu
Keyword(s):  
Time Series ◽  
Ground Vehicles ◽  
Durability Test ◽  
Test Analysis ◽  
Event Identification ◽  
Test Synthesis ◽  
Durability Testing ◽  
Vehicle Test ◽  
Accelerated Durability Test ◽  
Mission Profile

The accelerated durability test can be achieved by using the GlyghWorks software through the process of Mission Profile and Test Synthesis. Mission profile comprises a number of load events that simulate the real world driving conditions, which contain dynamic information about the vehicle. Test Synthesis is accomplished with extracting the information on the frequency of the events expected in the service life. The challenge of accurately separating the time series signal that correlate the load events becomes essential in order to efficiently conduct the accelerated durability test analysis. In this paper, a method is developed for automatic event identification from a time series based on wavelet analysis, clustering, and Fourier analysis, which are applied respectively to denoise, cluster and refine the segmentation of respective events embedded in the time series signal. The identified events and their corresponding data are used to generate the accelerated durability testing profiles. A systematic approach of acceleration time series generation for the partial test based on the durability testing PSD profile will also be shown, and then the created loading profile can be directly applied as the driven profile in the lab test. Subsequently, method of validation process for the partial test will be introduced.

Synthesis and characterization of a polyester/styrene resin obtained by frontal polymerization

e-Polymers ◽  
2002 ◽  
Vol 2 (1) ◽  
Author(s):  
Stefano Fiori ◽  
Giulio Malucelli ◽  
Alberto Mariani ◽  
Laura Ricco ◽  
Elena Casazza
Keyword(s):  
Free Radical ◽  
Mechanical Behaviour ◽  
Unsaturated Polyester ◽  
Front Velocity ◽  
Frontal Polymerization ◽  
Maximum Temperature ◽  
Synthesis And Characterization ◽  
Free Radical Initiator ◽  
First Time

AbstractThe frontal polymerization technique has been successfully applied, for the first time, to obtain an unsaturated polyester/styrene resin. The effect of the ratio of the two aforementioned components, as well as of the type and amount of free-radical initiator on both front velocity and maximum temperature reached by the front, has been thoroughly studied. The resulting products have been characterized in terms of their thermal and dynamic-mechanical behaviour. A comparison of such products with the corresponding materials obtained by the classical batch polymerization technique has evidenced that frontal polymerization allows to reach a higher degree of crosslinking with respect to batch copolymerization and hence a better thermal and mechanical behaviour.

scholarly journals Wattle and Daub Experimental Workshop: Durability Testing after 14 years of Uninterrupted Use

2018 ◽  
Vol 3 (12) ◽  
pp. 78-83
Author(s):  
María Guadalupe Cuitiño Rosales ◽  
Alfredo Esteves
Keyword(s):  
Optimum Condition ◽  
Thermal Energy ◽  
Auxiliary Heating ◽  
Energy Research ◽  
Durability Test ◽  
Durability Testing ◽  
Experimental Workshop ◽  
The City ◽  
Useful Lifetime ◽  
Over Time

An important factor to analyze when studying the useful lifetime of earth constructions is the detection of any constructive pathologies that may occur; an important consideration when building a house; yet in Argentina information on building with wattle and daub is scarce. This paper describes a durability test conducted on an experimental workshop built with wattle and daub technology in 2004, in the city of Mendoza, Argentina. The building has a floor area of 33.63 m2 (5.70 m x 5.90 m), and houses an experimental workshop for thermal energy research and the construction of solar equipment. During the 14 years that the workshop has been in use, the wattle and daub walls have been exposed to various environmental forces, such as rain, wind, and earthquakes. However, its thermal behavior has remained constant over time, maintaining a difference in temperature of 5.8ºC between the inside and outside without auxiliary heating. In general, the construction has been well-preserved and serves the purpose for which it was built, thus proving that wattle and daub constructions will remain in optimum condition for at least 14 years with minimal maintenance required to prevent surface materials from deteriorating.

scholarly journals Signed, Sealed, and Delivered with Trust: Non-Resident Citizens’ Experiences of Newly Adopted Postal Voting

2021 ◽  
Vol 3 ◽  
Author(s):  
Hanna Wass ◽  
Johanna Peltoniemi ◽  
Marjukka Weide ◽  
Miroslav Nemčok
Keyword(s):  
Political Legitimacy ◽  
Health Crisis ◽  
Parliamentary Elections ◽  
Proxy Voting ◽  
Global Pandemic ◽  
Physical Presence ◽  
Voting Procedures ◽  
Critical Components ◽  
First Time ◽  
Country Specific

The COVID-19 pandemic has made it clear that the traditional “booth, ballot, and pen” model of voting, based on a specific location and physical presence, may not be feasible during a health crisis. This situation has highlighted the need to assess whether existing national electoral legislation includes enough instruments to ensure citizens’ safety during voting procedures, even under the conditions of a global pandemic. Such instruments, often grouped under the umbrella of voter facilitation or convenience voting, range from voting in advance and various forms of absentee voting (postal, online, and proxy voting) to assisted voting and voting at home and in hospitals and other healthcare institutions. While most democracies have implemented at least some form of voter facilitation, substantial cross-country differences still exist. In the push to develop pandemic-sustainable elections in different institutional and political contexts, variation in voter facilitation makes it possible to learn from country-specific experiences. As accessibility and inclusiveness are critical components of elections for ensuring political legitimacy and accountability these lessons are of utmost importance.In this study, we focus on Finland, where the Parliament decided in March 2021 to postpone for two months the municipal elections that were originally scheduled to be held on April 18. Although the decision was mostly justified by the sudden and dramatic daily increase in new COVID-19 infections, the inability to guarantee the opportunity to vote for those in quarantine was included among the likely risks. The failure to organize health-safe voting procedures to accommodate the original schedule emphasizes a certain paradox in the Finnish electoral legislation: caution in introducing new facilitation instruments has led to lower levels of preparedness and flexibility in crisis situations. Although a forerunner in implementing extensive advance voting opportunities, Finland has only recently introduced postal voting, which is restricted to voters living abroad. Hence, we ask: what can be learned from this form of convenience voting if expanded to all voters to enhance the sustainability of elections?Our analyses are based on a survey conducted among non-resident voters (n = 2,100) after the 2019 parliamentary elections in which postal voting from abroad was allowed for the first time. Our results show that whereas trust in the integrity of postal voting is quite high, various efforts needed from individual voters substantially increase the costs of postal voting. Postal operations also raise concerns. Furthermore, voters felt that requiring two witnesses made postal voting cumbersome, an issue that needs to be resolved, particularly if applying postal voting in the context of a pandemic. The Finnish case constitutes a concrete example of a situation in which voter facilitation targeted to a particular segment of society may become a testbed for electoral engineering that will improve voting opportunities for everyone.

scholarly journals Thermophilic Fungi: Their Physiology and Enzymes

2000 ◽  
Vol 64 (3) ◽  
pp. 461-488 ◽  
Author(s):  
Ramesh Maheshwari ◽  
Girish Bharadwaj ◽  
Mahalingeshwara K. Bhat
Keyword(s):  
Extracellular Enzymes ◽  
Maximum Temperature ◽  
Thermophilic Fungi ◽  
Breakdown Rate ◽  
Ambient Temperatures ◽  
Experimental Systems ◽  
Heat Stable ◽  
Terrestrial Habitats ◽  
Eukaryotic Organisms ◽  
First Time

SUMMARY Thermophilic fungi are a small assemblage in mycota that have a minimum temperature of growth at or above 20°C and a maximum temperature of growth extending up to 60 to 62°C. As the only representatives of eukaryotic organisms that can grow at temperatures above 45°C, the thermophilic fungi are valuable experimental systems for investigations of mechanisms that allow growth at moderately high temperature yet limit their growth beyond 60 to 62°C. Although widespread in terrestrial habitats, they have remained underexplored compared to thermophilic species of eubacteria and archaea. However, thermophilic fungi are potential sources of enzymes with scientific and commercial interests. This review, for the first time, compiles information on the physiology and enzymes of thermophilic fungi. Thermophilic fungi can be grown in minimal media with metabolic rates and growth yields comparable to those of mesophilic fungi. Studies of their growth kinetics, respiration, mixed-substrate utilization, nutrient uptake, and protein breakdown rate have provided some basic information not only on thermophilic fungi but also on filamentous fungi in general. Some species have the ability to grow at ambient temperatures if cultures are initiated with germinated spores or mycelial inoculum or if a nutritionally rich medium is used. Thermophilic fungi have a powerful ability to degrade polysaccharide constituents of biomass. The properties of their enzymes show differences not only among species but also among strains of the same species. Their extracellular enzymes display temperature optima for activity that are close to or above the optimum temperature for the growth of organism and, in general, are more heat stable than those of the mesophilic fungi. Some extracellular enzymes from thermophilic fungi are being produced commercially, and a few others have commercial prospects. Genes of thermophilic fungi encoding lipase, protease, xylanase, and cellulase have been cloned and overexpressed in heterologous fungi, and pure crystalline proteins have been obtained for elucidation of the mechanisms of their intrinsic thermostability and catalysis. By contrast, the thermal stability of the few intracellular enzymes that have been purified is comparable to or, in some cases, lower than that of enzymes from the mesophilic fungi. Although rigorous data are lacking, it appears that eukaryotic thermophily involves several mechanisms of stabilization of enzymes or optimization of their activity, with different mechanisms operating for different enzymes.

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