scholarly journals Dynamic strain measurement of propeller shaft vibrations

2021 ◽  
Vol 2091 (1) ◽  
pp. 012050
Author(s):  
G A Kushner
Keyword(s):  
Strain Measurement ◽  
Operating Conditions ◽  
Dynamic Strain ◽  
Destructive Testing ◽  
Rotating Shaft ◽  
Actual Measurement ◽  
Shaft Line ◽  
Operation Conditions ◽  
Hardware Complex ◽  
Stochastic Loads

Abstract The paper proposes an approach to the registration of vibrations parameters to increase the reliability and predict the durability of technical systems with a continuously rotating shaft. For systems with stochastic loads, such as a ship’s shaft line, the actual measurement of shaft stresses and deformations is an actual way to prevent failures and non-destructive testing under operating conditions. The adaptation of the dynamic strain measurement method made it possible to develop a software and hardware complex for recording and analysing transverse, torsional and longitudinal vibrations of shafts. The design of a hardware complex consisting of a measuring mobile and stator modules connected by a wireless network that allows dynamic strain measurement is proposed. The connection diagram and the main metrological and technical characteristics of the modules are given. To test the operability of the hardware complex, an experimental installation was built that allows carrying out investigation of the shaft line vibrations in real operation conditions. Experimental data are presented, the analysis of which allows us to predict the durability of the system.

scholarly journals A Tamper-Resistant Algorithm Using Blockchain for the Digital Tachograph

Electronics ◽  
2021 ◽  
Vol 10 (5) ◽  
pp. 581
Author(s):  
Yongbae Kim ◽  
Juyong Back ◽  
Jongweon Kim
Keyword(s):  
Wireless Communication ◽  
Statistical Tests ◽  
Operating Conditions ◽  
External Memory ◽  
Data Recording ◽  
Storage Devices ◽  
Suggested Algorithm ◽  
Operation Conditions ◽  
Before And After ◽  
Verification Test

A tachograph in a vehicle records the vehicle operating conditions, such as speed, distance, brake operation conditions, acceleration, GPS information, etc., in intervals of one second. For accidents, the tachograph records information, such as the acceleration and direction of a vehicle traveling in intervals of 1/100 s for 10 s before and after the accident occurs as collision data. A vehicle equipped with a tachograph is obliged to upload operation data to administrative organizations periodically via other auxiliary storage devices like a USB attached external memory or online wireless communication. If there is a problem with the recorded contents, data may be at risk of being tampered with during the uploading process. This research proposed tamper-resistant technology based on blockchain for data in online and offline environments. The suggested algorithm proposed a new data recording mechanism that operates in low-level hardware of digital tachographs for tamper-resistance in light blockchains and on/offline situations. The average encoding time of the proposed light blockchain was 1.85 ms/Mb, while the average decoding time was 1.65 ms/Mb. With the outliers in statistical tests removed, the estimated average encoding and decoding time was 1.32 ms/Mb and 1.29 ms/Mb, respectively, and the tamper verification test detected all the tampered data.

scholarly journals Modeling of a Real-Life Industrial Reactor for Hydrogenation of Benzene Process

Catalysts ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 412
Author(s):  
Mirosław K. Szukiewicz ◽  
Krzysztof Kaczmarski
Keyword(s):  
Catalyst Activity ◽  
Real Life ◽  
Operating Conditions ◽  
Reactor Operation ◽  
Reactor Model ◽  
High Scale ◽  
Industrial Reactor ◽  
Knowledge Based ◽  
Operation Conditions ◽  
Insight Into

A dynamic model of the hydrogenation of benzene to cyclohexane reaction in a real-life industrial reactor is elaborated. Transformations of the model leading to satisfactory results are presented and discussed. Operating conditions accepted in the simulations are identical to those observed in the chemical plant. Under those conditions, some components of the reaction mixture vanish, and the diffusion coefficients of the components vary along the reactor (they are strongly concentration-dependent). We came up with a final reactor model predicting with reasonable accuracy the reaction mixture’s outlet composition and temperature profile throughout the process. Additionally, the model enables the anticipation of catalyst activity and the remaining deactivated catalyst lifetime. Conclusions concerning reactor operation conditions resulting from the simulations are presented as well. Since the model provides deep insight into the process of simulating, it allows us to make knowledge-based decisions. It should be pointed out that improvements in the process run, related to operating conditions, or catalyst application, or both on account of the high scale of the process and its expected growth, will remarkably influence both the profits and environmental protection.

scholarly journals Alginate/porous silica matrices for the encapsulation of living organisms: tunable properties for biosensors, modular bioreactors, and bioremediation devices

2015 ◽  
Vol 2 (1) ◽  
Author(s):  
Mercedes Perullini ◽  
Mariano Calcabrini ◽  
Matías Jobbágy ◽  
Sara A. Bilmes
Keyword(s):  
Physical Stability ◽  
Porous Silica ◽  
Biological Response ◽  
Optical Quality ◽  
Operating Conditions ◽  
Radius Of Gyration ◽  
Host Matrix ◽  
Operation Conditions ◽  
Step Procedure ◽  
Living Organisms

Abstract:The encapsulation of living cells within inorganic silica hydrogels is a promising strategy for the design of biosensors, modular bioreactors, and bioremediation devices, among other interesting applications, attracting scientific and technological interest. These hostguest multifunctional materials (HGFM) combine synergistically specific biologic functions of their guest with those of the host matrix enhancing their performance. Although inorganic immobilization hosts present several advantages over their (bio)polymer-based counterparts in terms of chemical and physical stability, the direct contact of cells with silica precursors during synthesis and the constraints imposed by the inorganic host during operating conditions have proved to influence their biological response. Recently, we proposed an alternative two-step procedure including a pre-encapsulation in biocompatible polymers such as alginates in order to confer protection to the biological guest during the inorganic and more cytotoxic synthesis. By means of this procedure, whole cultures of microorganisms remain confined in small liquid volumes generated inside the inorganic host, providing near conventional liquid culture conditions.Moreover, the fact of protecting the biological guest during the synthesis of the host, allows extending the synthesis parameters beyond biocompatible conditions, tuning the microstructure of the matrix. In turn, the microstructure (porosity at the nanoscale, radius of gyration of particles composing the structure, and fractal dimension of particle clusters) is determinant of macroscopic parameters, such as optical quality and transport properties that govern the encapsulation material’s performance. Here, we review the most interesting applications of the two-step procedure, making special emphasis on the optimization of optical, transport and mechanical properties of the host as well as in the interaction with the guest during operation conditions.

Speed Estimation of a Three Phase Induction Motor Using Stator Dynamic Strain Measurement by Fiber Bragg Grating Sensor based in SVR

2021 ◽  
Author(s):  
Rafael Mancuso Paraiso Cavalcanti ◽  
Jaqueline Bierende ◽  
Beatriz Brusamarello ◽  
Jean Carlos Cardozo Da Silva ◽  
Giovanni Alfredo Guarneri ◽  
...  
Keyword(s):  
Fiber Bragg Grating ◽  
Induction Motor ◽  
Strain Measurement ◽  
Fiber Bragg Grating Sensor ◽  
Dynamic Strain ◽  
Bragg Grating ◽  
Speed Estimation ◽  
Three Phase ◽  
Bragg Grating Sensor

scholarly journals Minimizing Vibratory Strain Measurement Error

1998 ◽  
Author(s):  
Mark D. Sensmeier ◽  
Kurt L. Nichol
Keyword(s):  
Measurement Error ◽  
Objective Function ◽  
Strain Gage ◽  
Strain Measurement ◽  
Measured Data ◽  
Dynamic Strain ◽  
Model Predictions ◽  
Modes Of Vibration ◽  
Instrumentation Error ◽  
Time Basis

Correlation between dynamic strain gage measurements and modal analysis results can be adversely affected by gage misplacement and gage misorientation. An optimization algorithm has been developed which allows the modeled strain gage locations and orientations to be varied within specified tolerances. An objective function is defined based on the least squares sum of the differences between experimental and model results. The Kuhn-Tucker conditions are then applied to find the gage locations and orientations which minimize this objective function. The procedure is applied on a one-time basis considering all measured modes of vibration simultaneously. This procedure minimizes instrumentation error which then allows the analyst to modify the model to more accurately represent other factors, including boundary conditions. Flat plate vibratory data was used to demonstrate a significant improvement in correlation between measured data and model predictions.

scholarly journals The use of thermography in the diagnosis of ship piston internal combustion engines

2018 ◽  
Vol 182 ◽  
pp. 01027
Author(s):  
Jan Monieta
Keyword(s):  
Infrared Thermography ◽  
Internal Combustion Engines ◽  
Experimental Studies ◽  
Internal Combustion ◽  
Technical Condition ◽  
Operating Conditions ◽  
Combustion Engines ◽  
Destructive Testing ◽  
Fault State ◽  
Floating Objects

The intensity of infrared radiation emitted by objects depends mainly on their temperature. One of the diagnostic signals may be the temperature field. In infrared thermography, this quantity is used as an indicator of the technical condition of marine objects. The article presents an overview of the use of infrared thermography for the diagnosis mainly of marine piston floating objects and various types of reciprocating internal combustion engines as well as examples of own research results. A general introduction to infrared thermography and common procedures for temperature measurement and non-destructive testing are presented. Experimental research was carried out both in laboratory conditions and in the operating conditions of sea-going vessels. Experimental studies consisted of the presentation of photographs of the same objects made in visible light and the use of infrared thermography. The same objects were also compared, but for different cylinders of the tested internal combustion engines as well as for the up state and fault state. The characteristics of the temperature values at selected points were taken depending on the engine load along with the approximation mathematical models of these dependencies.

scholarly journals Research on the Energy Efficiency Indicators of Transport Diesel Engines under Transient Operation Conditions

Pomorstvo ◽  
2018 ◽  
Vol 32 (2) ◽  
pp. 228-238 ◽  
Author(s):  
Sergejus LebedevasPaulius ◽  
Paulius Rapalis ◽  
Rima Mickevicienė
Keyword(s):  
Diesel Engine ◽  
Diesel Engines ◽  
Engine Performance ◽  
Mechanical Efficiency ◽  
Operating Conditions ◽  
Efficiency Coefficient ◽  
Operation Conditions ◽  
Power Increase ◽  
Control Units ◽  
Additional Equipment

In this study, we have investigated the efficiency of transport diesel engines CAT3512B-HD in transient braking and acceleration modes in 2M62M locomotives. A comparative analysis of the diesel engine performance has been performed at speeds of power increase and braking ranging from 4–5 kW/s to 17–18 kW/s. A decrease in the fuel economy occurred, and the main reason for it (compared with the steady-state operating condition at qcycl = idem) has been found to be the deterioration of the mechanical efficiency coefficient due to the loss of the additional equipment kinetic energy of the engine. The efficiency decreased by 3–3.5% under power increase operations and by 10–14% in the braking modes. The original methodology for the evaluation of the diesel engine parameters registered by the engine control units (ECU) in the engine operating conditions, mathematical modelling application AVL BOOST, and analytical summaries in artificial neural networks (ANNs) have been used. The errors in the obtained results have been 5–8% at a determination coefficient of 0.97–0.99.

scholarly journals Prediction of fatigue limit of journal bearings considering a multi-axial stress state

2016 ◽  
Vol 68 (3) ◽  
pp. 430-438 ◽  
Author(s):  
Christopher Sous ◽  
Henrik Wünsch ◽  
Georg Jacobs ◽  
Christoph Broeckmann
Keyword(s):  
Stress State ◽  
Axial Stress ◽  
Design Guidelines ◽  
Journal Bearings ◽  
Operating Conditions ◽  
Test Results ◽  
Content Type ◽  
Operation Conditions ◽  
Component Test ◽  
Material Tests

Purpose The purpose of this paper is to investigate the applicability of the quadratic failure hypothesis (QFH) on journal bearings coated with a white metal sliding layer on the prediction of safe and unsafe operating conditions. The hypothesis covers operation conditions under static and dynamical loading. Design/methodology/approach Material tests and elastohydrodynamic, as well as structural, simulations were conducted to provide the required input data for the failure hypothesis. Component samples were tested to verify the results of the QFH. Findings The load bearing capacity of journal bearings was analysed for different operating conditions by the use of the QFH. Results allow for the identification of critical and non-critical loading conditions and are in accordance with component test results. Originality/value Today’s design guidelines for journal bearings do not consider a multi-axial stress state and actual stress distribution. The applied hypothesis enables consideration of multiaxiality inside the sliding surface layer, as well as determining the location of bearing fatigue due to material overload.

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