Part Of Technology Research Articles

Impact of mustard biodiesel and clove oil additives on particulate matter emission and carbon deposition in diesel engines

Recent studies suggest that the world is facing an energy crisis due to the depletion of fossil fuel reserves. To combat this issue, researchers have turned to biodiesel, a renewable bioenergy source made from vegetable oils, microalgae, and animal fats. A recent study analysed engine parts’ particulate matter emissions and carbon deposition during the long-term use of mustard biodiesel and clove oil as antioxidants in a compression ignition engine. Three samples of fuels: DF (diesel fuel), B30 (30% mustard biodiesel and 70% DF), and biodiesel blended fuel with 3000 PPM in a single-cylinder CI engine. The use of 30% biodiesel in diesel fuel (B30) for the endurance test was based on a good mix. The engine was run for 100 h to investigate the particulate matter emissions and carbon deposition. The particulate matter emission data was collected every 25 h, and for carbon deposition, the engine’s fuel injector was turned off after 100 h of engine running. The results showed a reduction in particulate matter emissions of about 9.97%, 13.367%, 7.24%, 14.64%, 5.3%, 12.32%, 1.88%, and 7.99% for PM1, PM2.5, PM7, and PM10 in biodiesel blended fuel and biodiesel blended fuel with clove oil, respectively. The deposition of clove oil added to biodiesel blended fuel in the fuel injector has been reduced compared with the other fuels. Carbon deposition of the fuel injector was analysed through SEM and EDX tests, and the results showed that the carbon content in biodiesel blended fuel was lower than in diesel fuel. The deposition of clove oil added to biodiesel blended fuel in the fuel injector has been reduced compared with biodiesel blended fuel.

Modeling of Residual Stress During EDM of AISI 4340 for Marine Propulsion Application

This investigation is conducted to estimate the extent of residual stress induced in the workpiece when machined on EDM. The Residual stresses induced post machining a product can led to lower life and inadequate failures during service. AISI 4340 finds its applicability in propulsion parts of marine engine and thus chosen as the material for study. Tungsten-Copper is selected as material for tool. Response Surface Methodology (RSM) with Central Composite Design (CCD) is utilized preparing the trails using current, on-time of pulse, voltage, and duty factor as machine variables. X-Ray Diffraction (XRD) was performed to estimate the d-space lattice of machined as well as un-machined specimens. Furthermore, Scanning Electron Microscopy (SEM) was executed to analyze effect of residual stress on surface post machining. The model suggested that voltage and on duration were crucial factors for residual stress while duty factor and current were less influential. Residual stress in the machined surface results from gradual heating and cooling during machining. The developed model was predicted to be accurate through the validation test. The micro-cracks resulted from the thermal stresses developed during machining of the workpiece.

Rapid screening of creep resistance in additive manufactured Ti-6Al-4V alloy

In this study, rapid screening of creep resistance for additively manufactured (AM) materials is enabled using an accelerated creep test (ACT) called the dynamic negative stepped test (DNST). Additively manufactured components are on the rise in aerospace systems, particularly turbine engine parts. It can be challenging to identify the AM process parameters that correspond to high-temperature strength and creep resistance. Tests are needed that rapidly screen and qualify creep resistance. In DNST, the temperature is held constant, and the specimen is taken through a series of load holds from high to low. The DNST contains two distinct characteristics: (1) the hold duration for each step is “dynamically” controlled to ensure the minimum-creep-strain-rate is achieved at every step, and (2) the “descending” profile maximizes damage accumulation while remaining on the edge of instability. The DNST assesses a material's ability to resist creep damage accumulated across multiple deformation mechanisms. In this study, electron beam melted Ti–6Al–4V, built at six (6) directions: 0°, 30°, 45°, 60°, 90°, and V, is tested using a four-step DNST at 650 °C. Analysis of the minimum-creep-strain-rate (at each step), creep ductility, and rupture were performed. A strain energy density (SED) benchmark metric was established to rapidly screen and classify creep resistance using an “Ashby-like” plot that balanced energy dissipated and energy dissipation rate. The creep resistance was found to be ranked from V, 60, 45, 30, 90, and 0 in descending order. Microstructural and crystallographic characterization revealed grain refinement progressing from the strain-free to the high-strain regions, indicative of dynamic recrystallization (DRX). Further observations revealed that the material's energy capacity increased with the alignment of the grains' long axis and tensile direction.

Highway tunnel safety detection and management

Highway tunnel is an important part of highway engineering, and its safety detection and management play a pivotal role in the construction and maintenance process of the whole project. However, due to the particularity of the tunnel itself, the engineering quality is difficult to guarantee, and there are many safety risks. With the continuous development of China's traffic industry, there are more and more highway tunnel construction, so safety detection and management is particularly important.

Pengaruh Surfaktan Polysorbate dan Lesitin Pada Pelumas Minyak Goreng Terhadap Temperatur Mesin dan Daya

The development of the automotive world to date has grown rapidly, especially two-wheeled vehicles. Large temperature changes in lubricating oil viscosity, even if the value is too low, will reduce the lubrication of engine parts, increase friction between metals, and cause engine parts to heat up quickly. Efforts to control and overcome excessive engine heat can replace mineral-based lubricating oils with environmentally friendly and biodegradable lubricating oils. The purpose of this study is to determine the effect of using a mixture of cooking oil and surfactants C64H124O26 and C42H80NO8P as engine lubricants on the power and temperature produced by motorized vehicles. The independent variables of this research are RPM variation and mixture of pure cooking oil with lecithin and polysorbate surfactant (2.5%, 5%, 7.5%). The dependent variables are engine temperature and power. The control variables of this research are testing at room temperature, 4 stroke 125CC matic vehicle, and Raw Material using Palm cooking oil. The test method uses an infrared thermo gun for temperature and Dyno test for the highest power test on the type of Cooking Oil + Polyosrbate 7.5% with an average overall power of 5.872, then for the lowest temperature on the type of Cooking Oil + Polysorbate 2.5% with an average value of 86.2ºC.

Exploring copper corrosion inhibition in value added neem biodiesel: Evaluation by traditional and machine learning approaches

Neem seed biodiesel is an eco-friendly fuel, however, to minimize its corrosion on copper metal used in engine parts, ethyl acetate extract of Syzygium aromaticum flowers was tested as an inhibitor. Copper corrosion evaluation in biodiesel revealed an inhibition efficiency of 97.96 %. Corrosion at the operating temperature of diesel engine was predicted by machine learning - quadratic regression. Thermodynamics and spectral evaluations bring to light the adsorption of inhibitors on the metal surface for inhibiting the corrosion of copper metal immersed in biodiesel. Surface morphological studies revealed the protective nature of the copper metal corrosion. Quadratic Surface Vector Machine (SVM) algorithm classified the corrosion classes as low, medium, and high with an overall accuracy value of 94.6 %. The percentage of non-corroded area of copper metal specimen in biodiesel medium with the said inhibitor as estimated with quadratic SVM is 97.193 %. The research findings suggest that the ethyl acetate extract of S. aromaticum flowers has the potential to perform as an effective corrosion inhibitor for copper in biodiesel medium and revealed the potential of quadratic SVM machine learning algorithm in corrosion estimation and classification.

The current status and trends of oral bone regeneration materials: a bibliometric analysis from 1991 to 2023

Objectives: Due to the complexity and importance of oral bone structure, oral bone regeneration materials differ from those used in other parts of the body. To study the research trends and hotspots of oral bone regeneration materials, this paper conducts a bibliometric analysis of related papers from 1991 to 2023 (retrieved on 27 September 2023).Materials and methods: Using bibliometric methods, two visualization metric software, Citespace and VOSviewer, were used to analyze 1217 papers in SCIE, including paper analysis, author analysis, country and institution analysis, keyword analysis, and cited literature analysis.Results: (Alavi et al., Oral Surgery Oral Medicine Oral Pathology Oral Radiology, 2023, 136 (5), 554–68) The number of papers is generally increasing and gradually stabilizing; (Xia et al., Bioactive Materials, 2021, 6 (11), 4186–208) Buser D is the most influential author, while Jung, Ronald E has the highest number of papers and total citations; (Wagner et al., Stem Cells Translational Medicine, 2019, 8 (10), 1084–91) The United States has the highest number of papers and citation frequency. The University of Bern and the University of Zurich in Switzerland are not only the institutions with the most papers but also the institutions with the most collaborations with other institutions. (Gallego et al., T Engineering Part A, 2010, 16 (4), 1179–87) Many research directions have persisted for decades since their inception. The field of oral bone regeneration materials is constantly developing and improving. In recent years, the research direction in this field may mainly focus on the role of blood cells and proteins in bone regeneration. (Wang et al., Japanese Dental Science Review, 2022, 58, 233–48). In recent years, the types of cited literature mainly include barrier membranes, alveolar ridge augmentation, bone graft materials, histological examination, and in vivo animal experimental models.Conclusion: The United States and Switzerland have a significant influence in the field of oral bone regeneration materials. The research hotspot in recent years is mainly on tissue engineering materials. However, traditional materials still occupy a large proportion in clinical treatment or research. In addition, the combined use of new and old materials has gradually become one of the research hotspots in this field.

Determination of Indicators for Optimal Selection of Technological Operations when Repairing Parts of Aircraft Gas Turbine Engines

Determination of Indicators for Optimal Selection of Technological Operations when Repairing Parts of Aircraft Gas Turbine Engines

Advanced Automation Detection of Cracks in Railway Tracks

Abstract: India’s transportation infrastructure relies heavily identification. The integration of IR sensors enables the early detection of cracks on the track surface, allowing for the timely identification of potential structural weaknesses, on the Indian Railways, which serves as a major means of long-distance travel for millions. Nevertheless, the discoveryof cracks on railway tracks still poses serious problems that can compromise safety if not addressed. This paper thereforedescribes a path-breaking effort towards a strong crack detection mechanism in railways. Our unique way involves integrating infrared (IR) sensors for crack detection and ultrasound sensors for object detection to entirely change track monitoring thereby enhancing railway safety and maintenance efficiency. The system presented is able to detect any possible hazards within targeted area thus leading to prevention-based action through proactive maintenance; italso reduces cases of accidents as early detections helps in minimizing their chances of occurrence by making use of real-time data from these sensors. Our method demonstratesits effectiveness through experiments, showing that it can detect both cracks and blocking objects on the train tracks, hence contributing towards better rail safety systems while offering a promising direction for pre- emptive maintenanceprograms and risk control strategies. Our study proposes an innovative remedy for the current issue of security inclusion along railway tracks. Withthis combination involving IRs as well as ultrasonic sensors, our device has fulltime surveillance applications so that they are able to intervene timely before accidents are caused by this malfunctioning parts of the locomotive engines.

Study the Corrosion Behavior of Low Carbon Steel Weldments Immersed in Tap Water

Corrosion is one of the main sources of failure for metals and alloys, thus it is a major engineering problem. Engineers must consider the corrosion of metals in different environments when designing engineering parts. Metals tend to corrode in different media; they show different behaviors due to differences in chemical composition and the severity of the corrosive medium. In tap water, the corrosion of mild steel products is an electrochemical phenomenon that includes two reactions: the dissolving of iron (anodic) and the reduction of oxygen (cathodic). This work observes the corrosion behavior of welded low-carbon steel by Friction Welding (FW), Shielded Metal Arc Welding (SMAW) , and MIG welding techniques using immersion tests in tap water at different periods. The results revealed that while the corrosion rate of Base Metal (BM) increases, it reaches a nearly steady state in the friction-welded and SMAW-welded samples. The difference in the corrosion rate of the welded samples can be attributed to changes in the concentrations of Cl– and CaCO3 ,as well as the pH values of the corrosive mediums. Pits could be observed in the microstructure of the nugget zone for all weldments.

Жароміцні інтерметалідні сплави та особливості їх легування

The work considers the prerequisites for the development of creep-resistant and heat-resistant alloys, based on intermetallics, taking into account the optimal combination of their physical and mechanical properties, as well as structural characteristics. It is shown that there is a sufficient number of intermetallics, which have a density lower than iron-based alloys, which, in combination with high melting temperatures and heat resistance, makes them promising materials for aerospace application, in particular, for gas turbine engine parts manufacturing. The most suitable creep-resistant and heat-resistant intermetallics can be called aluminides and silicides of titanium, nickel and molybdenum. For these compounds, it is possible to combine high values of specific strength with alloying-favorable types of crystal lattice. One of the most important and common creep-resistant alloys based on intermetallics is Ni3Al with FCC lattice. For this material, complex optimized alloying is the main way to increase creep resistance. The heat resistance of such alloys is significantly increased by applying ceramic coatings. Titanium aluminides Ti3Al and TiAl mainly have only a low density among the advantages. Their fragility at room temperatures and tendency to superplasticity at high temperatures significantly limits their application. The impact of disadvantages may be reduced by applying thermomechanical processing of such materials, which aims to change their structure. Alloying titanium aluminides with a large amount of niobium was chosen as a solution that significantly reduced marked week sides of Ti-Al intermetallic alloys. As a result, this led to the creation of a new alloy based on intermetallic Ti2AlNb with a high set of operational characteristics. Mo-Si and Mo-Si-B can be considered as one of the most perfect systems for creating heat-resistant intermetallic alloys. They combine an acceptable density, high creep and heat resistance, which can be additionally increased by reinforcing with ceramic particles. Keywords: intermetallic-based alloys, creep resistance, alloying, Ni-Al, Ti-Al, Mo-Si, Mo-Si-B.

Grinding of Thermal Spray Coated Aircraft Engine Parts

Aircraft engines that must be certified separately from the platform should comply airworthiness and remain unchanged for all types of operations and in all environments. Together with this, they might only be preferred by airlines if they are competitive in terms of several aspects such as fuel efficiency, speed, and maintainability. These requirements are met by an interdisciplinary effort including engine design, component materials, manufacturing techniques and electronic control. An illustrative example to this is the critical components designed and manufactured of titanium or superalloys and coated afterwards to resist various wear causes and to facilitate easy, cost-effective maintenance by keeping the component itself only via renewing the coating after certain flight hours. Although this solution sounds reasonable and feasible, it needs a considerable know-how level to apply a proper coating and subsequently to size it to an acceptable level of dimensional quality and surface integrity. In order to meet researchers' and engineers' know-how needs on the subject, this paper presents a systematic review on grinding of thermal spray coated aircraft engine parts. In this paper, spray coatings, which offer the widest substrate material range are explained in detail regarding their materials, application methods and characterizations. Later on, grinding of these is narrated considering tools and process parameters such as cutting speed, feed, and depth of cut. Finally, the influence of grinding conditions on dimensions, surface quality, hardness, residual stresses, and microstructure is discussed. The paper is concluded with a state-of-the-art summary and emphasis on research gaps and future perspectives on the subject.

GROM: A generalized routing optimization method with graph neural network and deep reinforcement learning

Routing optimization, as a significant part of Traffic Engineering (TE), plays an important role in balancing network traffic and improving quality of service. With the application of Machine Learning (ML) in various fields, many neural network-based routing optimization solutions have been proposed. However, most existing ML-based methods need to retrain the model when confronted with a network unseen during training, which incurs significant time overhead and response delay. To improve the generalization ability of the routing model, in this paper, we innovatively propose a routing optimization method GROM which combines Deep Reinforcement Learning (DRL) and Graph Neural Networks (GNN), to directly generate routing policies under different and unseen network topologies without retraining. Specifically, for handling different network topologies, we transform the traffic-splitting ratio into element-level output of GNN model. To make the DRL agent easier to converge and well generalize to unseen topologies, we discretize the huge continuous traffic-splitting action space. Extensive simulation results on five real-world network topologies demonstrate that GROM can rapidly generate routing policies under different network topologies and has superior generalization ability.

Investigations on the interaction of laser parameters for efficient microdrilling of NiTiV smart alloy system

Ni–Ti shape memory alloys (SMAs) are popular in current research due to their usefulness and mechanical properties. At different temperatures, Ni–Ti alloys transition from austenite to martensite. To restore high-temperature memory in nickel-titanium SMAs, vanadium (V) is added as an alloying element. For Ni–Ti-based SMAs, the fiber laser is one of the best machining procedures for bio-implants, actuators, and aircraft engine parts. Using a Box–Behnken design to experiment with laser power, nozzle distance, cutting speed, and frequency, this study examines fiber laser micro-drilled Ni50Ti48V2 SM alloy material removal and hole taper angle. By increasing power (P), frequency (F), and cutting speed (C S ), Ni50Ti48V2 alloy material removal rate (MRR) increased by 75.79%. The hole taper angle (HTA) dropped 75.33% when cutting speed, laser power and frequency decreased. Lowering cutting speed and laser power increases micro-hole circularity and reduces HTA. Upon surface topographical inspection, debris and molten materials were found on the drilled surface. The flow of nitrogen gas caused materials to diffuse on the Ni50Ti48V2 alloy’s entry and exit surfaces, changing surface roughness. High parameters influence surface roughness, HTA, and circularity due to nitrogen gas flow. The material’s DSC and XRD tests confirmed its suitability for biomedical microhole production.

Emergence of Coated Piston Ring Scuffing Behavior on an Application-Oriented Tribological Model Test System

A major problem in lubricated piston ring/cylinder liner contact sliding systems is the tribological failure mechanisms known as scuffing. In order to evaluate and better understand this damage phenomenon in these tribological systems, a tilted linear tribometer (TE77) for application-oriented reciprocating model tests was developed and validated with scuffed field engine parts. With precise oil lubrication, original engine parts, such as CKS-coated piston rings (chromium-based coating with included aluminum oxides), original liners and fully formulated lubrications, were tested under conditions similar to the most critical part of the internal combustion engines (ICEs), known as fired top dead center (FTDC). Various in situ measurements during the tests allowed for a detailed investigation of the damage processes (crack transformation) on the tribological components. For the coated piston ring, vertical cracks were attributed to residual stresses, while horizontal cracks resulted from shear stresses. The crack transformation and wear results from other studies were confirmed for the liner. The results from FIB (Focused Ion Beam) cuts, along with EDS and SEM analyses, revealed that Fe (deriving from material transfer) acts as a catalyst on the CKS layer for the tribopads and that zinc sulfides are not present everywhere.

Effect of phase difference in pulsed pressure on fatigue crack propagation life of engine heat shield

abstract Heat shield is one of the important parts in aero engine, its function is to effectively prevent engine overheating. Under normal operation, the heat shield is subjected to high temperature from the combustion chamber and pressure pulsations inside and outside, and the phase difference of this pulsation pressure results in a very harsh working environment. Based on the experimental results, the approximate equation of the pulsating pressure is established, and the finite element method (FEM) is used to simulate the pulsating pressure. Meanwhile, the mechanical quantities such as thermal stress and mechanical stress are considered comprehensively. Linear elastic fracture mechanics (LEFM), Paris and Forman-Newman-de Koning (FNK) models were employed during the study in order to calculate the fatigue crack propagation life (FCPL) of the heat shield. The results show that the heat shield has an infinite lifetime at a phase difference of zero. As the phase difference increases, the FCPL and critical crack length (CCL) tend to decrease nonlinearly. When the phase difference is π, the FCPL and CCL are the shortest, which are only 3% and 17.1% of those at π/6. This study can provide a reference for the improvement and overhaul of heat shields.

Developing technology of directed energy deposition of workpieces of parts of aircraft engines from heat-resistant nickel alloys by means of using layer-by-layer microplasma surfacing method

Developing technology of directed energy deposition of workpieces of parts of aircraft engines from heat-resistant nickel alloys by means of using layer-by-layer microplasma surfacing method

Research on active vibration control of blade using variable-step-size filtered-x least mean square algorithm

The engine blade is one of the important parts of the aero engine, vibration can lead to engine blade off or fracture. Active Vibration Control (AVC) has a higher flexibility is increasingly used to suppress the vibration of the blade. The filtered-x least mean square (FxLMS) algorithm is an adaptive algorithm commonly used in active vibration control, but its fixed step size has a contradiction between convergence speed and steady-state error. A new variable-step-size FxLMS (VSSFxLMS) algorithm based on hyperbolic secant function was proposed, and the sech function ensures the control signal is bounded. In the early stage, a larger step size enables the error to decrease rapidly. The step size decreases as the error decreases, and a smaller step size ensures a smaller steady-state error. Firstly, this paper summarizes three VSSFxLMS algorithms and proposes an improved algorithm; Secondly, it compares and analyses the mentioned algorithms; Then, a joint simulation platform using ADAMS and Simulink is built to verify the effectiveness of the proposed algorithms; Finally, an experimental platform was built to complete the blade vibration active control experiments using several VSSFxLMS algorithms, and the results of the experiment verify the better vibration suppression effect of the proposed algorithm.

Effect of zirconium carbide coating on thermal behavior of heavy duty V12 diesel engine using finite element method

Thermal losses and emissions are considered as major contributing factors in decreasing the efficiency of engines and life span of engines. To prevent heat losses and emissions, thermal ceramic coatings are considered as potential contenders. Moreover, ceramic coatings also prevent engine parts from damage due to thermal stresses. In this computational study, the effect of Zirconium Carbide coating on the thermal behavior of V12 engine is explored. Geometry of V12 engine’s piston and cylinder is generated in SolidWorks 2016. After that, piston’s surface and cylinder’s inner walls are coated with Zirconium Carbide ceramic coating and thermal behavior is analyzed using ANSYS Workbench 19.2. Two cases are discussed in this work. In the first case, piston is made of Al-3003 alloy and cylinder walls are made of gray cast iron whereas in the second case, whole assembly is made of Al-3003 alloy. Temperature and heat flux profiles of both the cases are compared with coating and without coating. Maximum temperature is recorded to be at the top of piston head surface. The results show 44.9% increase in maximum temperature for the first case whereas 83.5% increase in the second case. Heat flux results after show reduction after coating. Zirconium Carbide ceramic coatings can act as thermal barrier and prevent engine parts from thermal stresses. Moreover, it provides insulation to cylinder which prevents heat transfer and retains more temperature inside the cylinder which in turn enhances the efficiency.

An ontology‐based digital test and evaluation master plan (dTEMP) compliant with DoD policy

AbstractTest and evaluation (TE) planning is a critical part of systems engineering. However, it has not received as much attention from digital engineering efforts as early‐stage design and analysis. Digital engineering has the potential to reduce the risk and effort associated with TE, while leveraging existing digital capabilities to add value. One aspect in particular that may benefit from such attention is the Department of Defense's Test and Evaluation Master Plan (TEMP). The purpose of the TEMP is to identify the key processes with respect to the TE of a product, and to specify the roles and responsibilities of key personnel and organizations. Concerns have been raised regarding the document‐based nature of the TEMP and the increased risk and reduced reward that this entails. In this paper, we investigate the potential benefits of digitalizing the TEMP and outline an incremental approach for achieving this. We also present a set of ontologies, collectively known as the Digital TEMP (dTEMP), and investigate potential benefits and limitations by applying the dTEMP to an example test program.