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DYNROT is a code based on the finite element method which is intended to perform a complete study of the dynamic behaviour of rotors. Although initially designed to solve the basic linear rotordynamic problems (Campbell diagram for damped or undamped systems, unbalance response, critical speeds, static loading), it can be used for the study of non‐stationary motions of nonlinear rotating systems and for the torsional analysis of rotors and reciprocating machines. Explains that one of the distinctive features of the code is the use of complex co‐ordinates, both for isotropic and non‐symmetric systems. Makes extensive use of complex arithmetics in all parts of the analysis. Applies the modal approach in some of the solution routines to increase the efficiency of the computation or to compute an equivalent viscous damping in those cases where hysteretic damping cannot be introduced directly to the model. The dynamics of bladed discs is included in the code.

This study aims to provide data references for deposit cleaning, fuel formulation and lubricant formulation.

The engine disassembly procedure was carried out based on the IO540 operation manual part number 60297-10-1-7 document. Except for the normal disassembly and assembly of the engine and the measurement of parts, the main test contents included break-in run operation, cylinder pressure test, oil consumption run, pretest calibration run, post-test calibration test and the most critical endurance test. The Lycoming IO-540-V4V5 engine and the customized Hartzell CK319 propeller were selected for the test run.

The deposits were mainly composed of C, O, B, Al, Br and Pb, which were mainly sourced from fuel, lubricating oil and body materials. XPS analysis showed that the presence of O determined the richness of the deposit components, giving the deposit structure with organic and inorganic components.

This work provides certain data support and reference for subsequent aircraft maintenance, fuel formula and lubricating oil formula. The long-term stability and safety of the aircraft run can be ensured through continuous research, improvement and optimizing the operating of the engine.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-08-2024-0300/

The purpose of this paper is to present an electro‐thermo‐structural analysis based on the cell method (CM).

CM is useful for solving coupled problems when the same geometrical discretization can be adopted for different phenomena. In this case, the same geometrical structures and operators can be used, leading to a simplification of the numerical model.

In order to asses the performance of the proposed coupling scheme, results have been compared with values measured on a carbon‐fiber specimen heated by an electric current and with an applied the mechanical load.

A new dynamic coupling scheme based on the CM has been proposed and assessed with respect to measurements. A good agreement between model results and measurements has been shown, at least until second order effects appears, like the breaking of some fibers of the specimen or high‐temperature effects on epoxy resin.

The paper aims to examine the inhibition effect of NiO nanoparticles and the influence of liquid nitrogen immersion on the corrosion behavior of (NiO)_x(Bi_1.6 Pb_0.4)Sr₂Ca₂Cu₃O_10-δ and (NiO)_x (Bi, Pb 2223), where x = 0.00 and 0.05 Wt.% phase superconductor in 0.1 M Na₂SO₄ at 30°C.

This study was done using open-circuit potential electrochemical impedance spectroscopy, potentiodynamic polarization curves and chronoamperometry measurements.

Potentiodynamic polarization technique showed that NiO nanoparticles suppress both the anodic and cathodic parts of the polarization curves of (NiO)_x(Bi, Pb)-2223 superconductor in 0.1 M Na₂SO₄ solution. A significant enhancement in the corrosion resistance of the prepared superconductors is observed on immersing them in liquid nitrogen. This is owing to the fact that immersion in liquid nitrogen increases the volume contraction of the superconductor matrix, causing the shrinkage of the pores and voids present in the samples and thus reducing the active surface area for the dissolution of (NiO)_x(Bi, Pb)-2223 superconductor matrix.

This paper fulfills the need to investigate the corrosion behavior of superconductors and the influence of liquid nitrogen immersion on such behavior.

The purpose of this paper is to study the effect of ultrasonic machining process parameters on surface quality while machining titanium alloy Ti-6Al-4V.

Effect of cryogenic treatment (CT) of tool and work material was also explored in the study. Taguchi’s L18 orthogonal array was chosen for design of experiments and average surface roughness was measured.

Different modes of fracture were detected at work surface corresponding to varied input process parameters. Slurry grit size, power rating and tool material along with CT of work material were found to be the significant parameters affecting surface quality.

The results obtained have been modelled using artificial neural network approach.

This study aims to simulate the influence of surface texturing produced via turning process toward pressure distribution and load capacity generation using computational fluid dynamics (CFD).

The dimple geometry was obtained via turning process, to be used for future application on piston skirt surfaces. Two cases were studied: a preliminary study using single periodic dimple assuming linear dimple distribution and an application study using multiple periodic dimples to address actual dimple orientation following the turning process.

For the first case, the dimple was proven to generate load capacity with regard to untextured surface, owing to the asymmetric pressure distribution. Increasing the Reynolds number, dimple width and dimple depth was found to increase load capacity. For the second case, although load capacity increases via surface texturing, the value was 97.4 per cent lower relative to the first case. This confirmed the importance of doing multiple dimple simulations for real applications to achieve more realistic and accurate results.

A new concept of dimple fabrication using a low-cost turning process has been developed, with a potential to increase the tribological performance under hydrodynamic lubrication. Previous CFD simulations to simulate these benefits have been done using a single periodic dimple, assuming equal distribution array between dimples. However, due to the different orientations present for dimples produced using turning process, a single periodic dimple simulation may not be accurate, and instead, multiple dimple simulation is required. Therefore, present research was conducted to compare the results between these two cases and to ensure the accuracy of CFD simulation for this type of dimple.

The purpose of this study is to investigate the application of non-destructive testing methods in measuring bearing oil film thickness to ensure that bearings are in a normal lubrication state. The oil film thickness is a crucial parameter reflecting the lubrication status of bearings, directly influencing the operational state of bearing transmission systems. However, it is challenging to accurately measure the oil film thickness under traditional disassembly conditions due to factors such as bearing structure and working conditions. Therefore, there is an urgent need for a nondestructive testing method to measure the oil film thickness and its status.

This paper introduces methods for optically, electrically and acoustically measuring the oil film thickness and status of bearings. It discusses the adaptability and measurement accuracy of different bearing oil film measurement methods and the impact of varying measurement conditions on accuracy. In addition, it compares the application scenarios of other techniques and the influence of the environment on detection results.

Ultrasonic measurement stands out due to its widespread adaptability, making it suitable for oil film thickness detection in various states and monitoring continuous changes in oil film thickness. Different methods can be selected depending on the measurement environment to compensate for measurement accuracy and enhance detection effectiveness.

This paper reviews the basic principles and latest applications of optical, electrical and acoustic measurement of oil film thickness and status. It analyzes applicable measurement methods for oil film under different conditions. It discusses the future trends of detection methods, providing possible solutions for bearing oil film thickness detection in complex engineering environments.

Piezoelectric materials are widely used as actuators, due to the advantages of quick response, high sensitivity and linear strain-electric field relationship. The previous work on the piezoelectric material plate structures is not enough; however, such structures play a very important role in the practical design. In this paper, the actuation performance of piezoelectric laminated plate actuator (PLPA) is analyzed based on Galerkin method to parametric study the shape control.

In this paper, the actuation performance of PLPA is analyzed based on Galerkin method to parametric study the shape control. The stress components of the matrix plate are formulated based on electro-mechanical coupling theory and Kirchhoff's classical laminated plate theory. The effectiveness of the developed method is validated by the comparison with finite element method.

The actuation performance of PLPA and its influencing factors are numerically analyzed through the developed method. The deflection of PLPA is reasonably increased by optimizing the electric fields, the piezoelectric patch and the matrix plate.

The Galerkin method can be used for engineering applications more easily, and it does not require to rebuild the calculation model as finite element method during the calculation and analysis of PLPA. This paper is a valuable reference for the design and analysis of PLPAs.

Model-based systems engineering (MBSE) is an important approach for the transforming process from “document-centered” to “model centered” systems engineering mode in equipment development, which can effectively shorten the equipment development cycle and improve product design quality. This paper aims to understand if MBSE enables to support manufacturing and equipment development.

The paper opted a bibliometric analysis of MBSE in domain of advanced manufacturing from different perspectives such as publication volume, research team, sources and keyword co-occurrence.

Firstly, the application of MBSE in advanced manufacturing can be roughly divided into three stages. And MBSE has been widely implemented globally and has gradually formed several noteworthy teams. Secondly, this article has identified some high-quality sources, with a large number of publications and citations, the most influential publications focus on the practice or guidance of digital twins and intelligent manufacturing. Thirdly, research can be divided into six categories, including systems engineering, digitalization, intelligent manufacturing, product design, model and architecture and MBSE applications.

Because of the chosen research approach, the visualized network tends to lose certain information such as a few keywords may be inaccurately categorized.

This paper comprehensively study the research status of MBSE in advanced manufacturing and forecasts future research trends, emphasizing the combination of intelligent manufacturing and digitization.

This paper fulfills an identified need to understand the current application status and future development trends of MBSE.

The lack of integrity of the piston machine combustion chamber manifests itself in leakages of the working fluid between the piston and the cylinder liner, at valves mounted in the cylinder head and between the head and the liner. An untight combustion chamber leads to decreased power output or efficiency of the engine, while leaks of a fluid may cause damage to many components of the chamber. The actual value of working chamber leak is a desired and essential piece of information for planning operations of a given machine.

This research paper describes causes and mechanisms of leakage from the working chamber of internal combustion engines. Besides, the paper outlines presently used methods and means of leak identification and states that their further development and improvements are needed. New methods and their applicability are presented.

The methods of leak identification have been divided into diagnostic and non-working machine leak identification methods. The need has been justified for the identification of leakage from the combustion chamber of a non-working machine and for using the leakage measure as the value of the cross-sectional area of the equivalent leak, defined as the sum of cross-section areas of all leaking paths. The analysis of possible developments of tightness assessment methods referring to the combustion chamber of a non-working machine consisted in modelling subsequent combustion chamber leaks as gas-filled tank leak, leak from another element of gas-filled tank and as a regulator of gas flow through a nozzle.

A measurement system was built allowing the measurement of pressure drop in a tank with the connected engine combustion chamber, which indicated the usefulness of the system for leakage measurement in units as defined in applicable standards. A pneumatic sensor was built for measuring the cross-sectional area of the equivalent leak of the combustion chamber connected to the sensor where the chamber functioned as a regulator of gas flow through the sensor nozzle. It has been shown that the sensor can be calibrated by means of reference leaks implemented as nozzles of specific diameters and lengths. The schematic diagram of a system for measuring the combustion chamber leakage and a diagram of a sensor for measuring the cross-sectional area of the equivalent leak of the combustion chamber leakage are presented. The results are given of tightness tests of a small one-cylinder combustion engine conducted by means of the set up measurement system and a pre-prototype pneumatic sensor. The two solutions proved to be practically useful.