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2017-10-08
Technical Paper
2017-01-2252
Weihua Sun, Wei Du, Xuefei Dai, Xiangdong Bai, Zhiping Wu
Getting real cylinder pressure is the basis of engine combustion analysis. Because of the advantages of good thermal performance, fast response, small size, high accuracy, large range and so on, piezoelectric quartz sensor is widely used in the measurement of the cylinder pressure. But this kind of sensor can only get the dynamic cylinder pressure which may not represent the real one. In this situation, the cylinder pressure needs to be corrected by some method. It also could cause great result divergences of the combustion analysis by using different cylinder pressure correction methods. This paper aims to acquire a proper cylinder pressure correction method by carrying out the theory analysis based on ideal gas equation and experiment research of cylinder pressure on a turbocharged eight-cylinder diesel engine.
2017-10-08
Technical Paper
2017-01-2455
Vikram Chopra
This paper reports on the design of a synchronizer brake based on permanent magnets, capable of braking with an active zero-slip load. Eddy-current brakes are widely used in automation and transportation applications; however, their use is limited by the rotor speed. For low-speed and high-torque applications, designs based on permanent magnets are better suited. Zero-slip braking torque is increased by the use of permanent magnets but, consequently, so is the cogging torque. At first, the synchronizer brake was designed with 16 surface magnets on the rotor. However, in order to reduce the permanent magnet mass, the rotor was re-designed with half the number of surface magnets. This novel design helped lower cogging torque and fabrication costs. Simulation of the design, using the 3D transient with motion solver in commercial finite element software, showed promising results.
2017-10-08
Technical Paper
2017-01-2196
Giuseppe Cicalese, Fabio Berni, Stefano Fontanesi, Alessandro D'Adamo, Enrico Andreoli
High performance Diesel engines are characterized by remarkable thermo-mechanical loads. Therefore, compared to spark ignition engines, designers are forced to increase component strength in order to avoid failures. By the way, 3D-CFD simulations represent a powerful tool for the evaluation of the engine thermal field and may be used by designers, along with FEM analysis, to prevent thermo-mechanical failures. The current work aims at providing an integrated in-cylinder/CHT methodology for the estimation of a Diesel engine thermal field. On one hand, in-cylinder simulations are fundamental to evaluate not only the global heat transfer at the combustion chamber walls, but also its point-wise distribution. In particular, thanks to an improved heat transfer model based on a modified thermal wall function, wall heat fluxes due to combustion are correctly estimated.
2017-10-08
Technical Paper
2017-01-2359
Yaodong Hu, Fuyuan Yang, Minggao Ouyang
Energy saving is becoming one of the most important issues for the next generation of commercial vehicles. The fuel consumption limits for commercial vehicles in China have stepped into the third stage, which is a great challenge for heavy duty commercial vehicles. Hybrid technology provides a promising method to solve this problem, of which the dual motor coaxial series parallel configuration is one of the best options. Compared with P2 configuration, the powertrain can not only operate in pure electric or parallel mode, but also can operate in series, which shows better flexibility. In this paper, regulations on test cycle, fuel consumption test methods and its limits of the third stage will be introduced and explained in detail. Then, the quasi static models of the coaxial series parallel powertrain with/without gearbox under C-WTVC cycle are built.
2017-10-08
Technical Paper
2017-01-2432
Xiangwang Li, Weimin Wang, Xiongcai Zou, Zhiming Zhang, Wenlong Zhang, Shemin Zhang, Tao Chen, Yuhuang Cao, Yuanda Chen
In order to reduce emissions, size and manufacturing cost, integrated exhaust manifold become popular in gasoline engine, especially in three-cylinder engine. Moreover, due to shorter length, lighter weight, and less component connections, the exhaust manifold and hot end durability will improve apparently. In this work, an advanced cylinder head with integrated exhaust manifold is in adopted in one three-cylinder turbo engine. Because of this integration characteristic, the gas retain in cylinder head longer and the temperature reach higher level than normal cylinder head, which will cause thermal fatigue failure more easily. To validate the exhaust manifold and hot end durability, series simulation and test validation work have been done. Firstly, overall steady state and transient temperature simulation was done for global model. The global model include cylinder head, block, turbocharger, and catalyst components.
2017-10-08
Journal Article
2017-01-2293
Jim Barker, Jacqueline Reid, Sarah Angel Smith, Colin Snape, David Scurr, Graham Langley, Krina Patel, Anastarsia Carter, Cris Lapthorn, Frank Pullen
Abstract Studies of diesel system deposits continue to be the subject of interest and publications worldwide. The introduction of high pressure common rail systems resulting in high fuel temperatures in the system with the concomitant use of fuels of varying solubilizing ability (e.g. ULSD and FAME blends) have seen deposits formed at the tip of the injector and on various internal injector components. Though deposit control additives (DCAs) have been successfully deployed to mitigate the deposit formation, work is still required to understand the nature and composition of these deposits. The study of both tip and internal diesel injector deposits (IDID) has seen the development of a number of bench techniques in an attempt to mimic field injector deposits in the laboratory. One of the most used of these is the Jet Fuel Thermal Oxidation Tester or JFTOT (ASTM D3241).
2017-10-08
Journal Article
2017-01-2446
Pengchuan Wang, Nikolaos Katopodes, Yuji Fujii
Wet clutch packs are the key component for gear shifting in the step-ratio automatic transmission system. They are coupled or de-coupled to alter gear ratios based on driver’s demand and vehicle operating conditions. The frictional interfaces between clutch plates are lubricated with automatic transmission fluid (ATF) for both thermal and friction management. In a 10-speed transmission, there may be as many as 6 clutch packs. Under any driving conditions, 2 to 3 clutch packs are typically open, shearing ATF and contributing to energy loss. There is an opportunity to improve fuel economy by reducing this viscous drag. One main factor that directly affects clutch drag is the clearance between rotating plates. The axial position of clutch plates changes continually at every instance. It is empirically known that not only the total clearance, but also its distribution between the plates affects the viscous drag.
2017-09-23
Technical Paper
2017-01-1982
Xiaoming Lan, Hui Chen, Xiaolin He, Jiachen Chen, Yosuke Nishimura, Kazuya Ando, Kei Kitahara
Abstract In the recent years, the interaction between human driver and Advanced Driver Assistance System (ADAS) has gradually aroused people’s concern. As a result, the concept of personalized ADAS is being put forward. As an important system of ADAS, Lane Keeping Assistance System (LKAS) also attracts great attention. To achieve personalized LKAS, driver lane keeping characteristic (DLKC) indices which could distinguish different driver lane keeping behavior should be researched. However, there are few researches on DLKC indices for personalized LKAS. Although there are many researches on modeling driver steering behavior, these researches are not sufficient to obtain DLKC indices. One reason is that most of researches are for double lane change behavior which is different from driver lane keeping behavior.
2017-09-19
Technical Paper
2017-01-2136
Almuddin Rustum Sayyad, Pratik Salunke, Sangram Jadhav
The objective of this work is to optimize the operating parameters of the Direct Injection single cylinder (5.2 kw) CI engine with respect to Brake Thermal Efficiency (BTHE), Hydro carbons (HC) and Carbon dioxide (CO2). For this investigation, we used Simarouba Biodiesel as an alternate fuel for diesel fuel which possesses low cetane number which is not sufficient to operate existing diesel engine. However, this could be combined with the diesel fuel in the form of blends. For this investigation four levels and four parameters were selected viz. Injection Pressure (IP), Fuel Fraction (FF), Compression Ratio (CR) and Injection Timing (Before TDC). Taguchi Method is used for minimizing the number of experiments and Multiple Regression Analysis is used to find the optimum condition. Three outputs variables such as; Brake Thermal Efficiency (BTHE), content of HC particles and CO2 in the emission are measured and considered its influence on CI Engine performance.
2017-09-19
Technical Paper
2017-01-2137
Dnyaneshwar V. Kadam, Sangram D. Jadhav
Vibration is the most considerable factor in dynamics of machinery. Vibration causes unfavorable effects on engine components and may reduce the life of engine. The conventional fossil fuel sources are limited in the world. The dependency on diesel should be reduced by using biodiesel as an alternative fuel in next few years. The input parameters are affected on engine performance and emission. The present study mainly focuses on an optimization of vibrations, performance and emission using Taguchi and multiple regression analysis for biodiesel as a fuel. The test was performed on single cylinder, four-stroke, diesel engine with VCR. Taguchi method is used to prepare the design of experiment of L16 array for minimizing number of experiments and multiple regression analysis for finding the best relationship between the input and output parameters. The selected input parameters are: fuel fraction, compression ratio, injection pressure and injection timing.
2017-09-19
Technical Paper
2017-01-2044
Mithilesh Kumar Sahu, Tushar Choudhary, Sanjay Y
Aircraft engines powering propulsion of the aircraft is the key component of the system. In aircraft industry it is desirable that an aircraft engines should supply high speeds (for military fighters) with low maintenance (for civil airplanes). In this regard an integration of gas turbine engines with traditional propeller has been introduced and termed as turboprop engine. In present work, a gas turbine with cooled blading has been proposed to be the turboprop engine which has been exergoeconomically analysed to assess the performance and economics related to the proposed turboprop engine. Exergoeconomic analysis is a tool which combines thermodynamic analysis and economic principles to provide information that is helpful to predict thermodynamic performance and total cost of the engine (thermal system). The methodology includes energy, exergy and cost balance equations for component-wise modelling of whole system.
2017-09-19
Technical Paper
2017-01-2125
Mohammad Barkat, Vivek Karan, Pradeep N
The exponential increase in the number of aircrafts and air travellers has triggered new innovations which aim to make airline services more reliable and consumer friendly. Quick and efficient maintenance actions with minimum downtime are the need of the hour. Areas that have a large potential for improvement in this regard are the real time use of diagnostic data, filtering/elimination of nuisance faults and machine learning capabilities with respect to maintenance actions. Although, numerous LRUs installed on the aircraft generate massive amounts of diagnostic data to detect any possible issue or LRU failure, it is seldom used in real time. The turnaround time for LRU maintenance can be greatly reduced if the results of the diagnostics conducted during LRU normal operation is relayed to ground stations in real-time. This enables the maintenance engineers to plan ahead and initiate maintenance actions well before the aircraft lands and becomes available for maintenance.
2017-09-19
Technical Paper
2017-01-2072
Yilian Zhang, Qingzhen Bi, Nuodi Huang, Long Yu, Yuhan Wang
Interference-fit riveting is a critical fastening technique in the field of aerospace assembly. The fatigue and sealing performance of the rivet joint are determined by the interference-fit level of the rivet joint. As a result, it is of great importance to measure the interference-fit level accurately and effectively. Conventional interference-fit level measurement methods can be divided into direct measurement (destructive test on test-piece) and indirect measurement (off-line dimensional measurement of upset rivet head). Both methods cannot be utilized in automatic riveting. In this paper, an on-line non-destructive measurement method is developed to measure the interference-fit level. By taking full advantage of servo-driving riveting integrated with force measurement, the force-deformation data of the deformed rivet can be obtained in real time. The recognized feature points from the force-deformation data can reflect the height of the upset rivet head.
2017-09-19
Technical Paper
2017-01-2021
Numair Mazgaonkar, Andrew Stankovich
For large aerospace assemblies in finite element (FE) analysis problems, contact interaction between the surrounding bodies has to be established to simulate the load transferred between the components, like aircraft engine carrying bracket assemblies, spigots assemblies etc., and understand the effects of interaction between respective parts. In some cases, depending upon geometry of the assembly, the region of study may not be contact area but the stresses acting within the parts themselves. If there is no geometric or material non-linearity in such problems, a new contact formulation method known as Fast Contact can be used in these contact regions. In this method, contact non-linearity could be introduced to simulate the problem but friction between the contacting parts should not be present. Currently, there is a scope for applying this method for solving FE problems in the aerospace and rail industry.
2017-09-19
Technical Paper
2017-01-2029
Thibaut BILLARD, Cedric Abadie, Bouazza Taghia
The present paper reports non-electrically intrusive partial discharge investigations on aeronautic and electric vehicle motors fed by SiC inverter drive under variable environmental conditions. A representative test procedure and experimental set-up based on operating aeronautic conditions are essential to ensure the accuracy and reliability of partial discharge test on aircraft systems to make informed decisions on insulation system design choice. The aim of this paper is to demonstrate the feasibility of partial discharge test of the insulation system on a different type of motor under such conditions, both electrically and environmentally. To do so, the paper will start by detailing the innovative experimental set-up to be used in the study. It mainly consists in a high-voltage (1000V) inverter drive using SiC components to provide fast rise time surges.
2017-09-19
Technical Paper
2017-01-2052
K Friedman, G Mattos, K Bui, J Hutchinson, A Jafri, J Paver PhD
Aircraft seating systems are evaluated utilizing a variety of impact conditions and selected injury measures. Injury measures like the Head Injury Criterion (HIC) are evaluated under standardized conditions using anthropometric dummies such as those outlined in 14 CFR part 25. An example would be a dummy seated in an upright position held with a two point belt decelerated from an impact speed and allowed to engage components that are in front of the dummy. Examples of head contact surfaces would include video monitors, a wide range of seat back materials, and airbags from which the HIC and other injury measures can be calculated. Other injury measures, such as Nij, are also of interest and can be measured with the Hybrid III dummy as well. A minimum deceleration pulse is defined as part of the regulations for a frontal impact. In this study the effect of variations in decelerations that meet the requirements is considered.
2017-09-19
Technical Paper
2017-01-2051
Vasanth Thanigaivelu, Samir Choksi
Testability addresses the extent to which a system or unit supports fault detection and fault isolation in a confident, timely and cost-effective manner. The incorporation of adequate testability, including Built-In Test (BIT), requires early end systematic management attention to testability requirements, design and measurement. Whilst the design of BIT has become a standard design practice for a complex control system, the process to measure the effectiveness of such circuitry (both hardware and software) remains qualitative. The Built-In Test Effectivity Analysis or BEA tries to quantify such analysis at each phase; identifying requirement gaps that help design safer products. The BEA modifies standard reliability programme to use Functional Failure Modes and Effects Analysis (FFMEA), and a reliability prediction of each functional group to generate a measure of how thoroughly the system can check itself.
2017-09-19
Journal Article
2017-01-2036
William Schley
Abstract Of all aircraft power and thermal loads, flight controls can be the most challenging to quantify because they are highly variable. Unlike constant or impulsive loads, actuator power demands more closely resemble random processes. Some inherent nonlinearities complicate this even further. Actuation power consumption and waste heat generation are both sensitive to input history. But control activity varies considerably with mission segment, turbulence and vehicle state. Flight control is a major power consumer at times, so quantifying power demand and waste heat is important for sizing power and thermal management system components. However, many designers sidestep the stochastic aspects of the problem initially, leading to overly conservative system sizing. The overdesign becomes apparent only after detailed flight simulations become available. These considerations are particularly relevant in trade studies comparing electric versus hydraulic actuation.
2017-09-19
Technical Paper
2017-01-2060
Joseph Dygert, Patrick Browning, Magdalena Krasny
The dielectric barrier discharge (DBD) has seen significantly increased levels of interest for its applications to various aerodynamic problems. The DBD produces stable atmospheric-pressure non-thermal plasma with highly energetic electrons and a variety of ions and neutral species. The resulting plasma often degrades the dielectric barrier between the electrodes of the device, ultimately leading to actuator failure. Several researchers have studied a variety of parameters related to degradation and time-dependent dielectric breakdown of various polymers such as PMMA or PVC that are often used in actuator construction. Many of these studies compare the degradation of these materials to that of borosilicate glass in which it is claimed that there is no observable degradation to the glass. Recent research at West Virginia University has shown that certain actuator operating conditions can lead to degradation of a glass barrier and can ultimately result in failure.
2017-09-19
Technical Paper
2017-01-2064
Parvez Alam M, Dinesh Manoharan, Satheesh Chandramohan, Sabarish Chakkath, Sunil MAURYA
In the present market, multiple sophisticate and expensive Thrust Test Rigs for Brushless Motors (BLDC Motor) are available making it impossible to conduct such thrust analysis on a regular and cost effective basis. Moreover the present test rigs are incapable to measure high Thrust values. This needs specialized thrust testing rig which is more expensive. This paper aims at Design & Development of the Small Scale Test Rig Setup for measurement of the thrust of any Brushless DC motor and helps in refining the Selection of motor and propeller. This is a set up based on cost efficiency factor to implement such rigs, test and for comparing the static thrust produced by the BLDC motor. The fairly simple construction contains a weighing machine, a Tachometer and a Wattmeter to measure the Thrust, RPM and the Current Drawn respectively, and provide comprehensive, accurate and efficient data coming from the BLDC Motor including the Propeller and Electronic Speed Control (ESC).
2017-09-19
Technical Paper
2017-01-2062
Tushar Choudhary, Mithilesh Sahu, Shreya KRISHNA
Solid oxide fuel cell (SOFC) is the most promising candidate for utilization of waste generated from the GT based power system. By coupling SOFC with gas turbine (GT) based power system, a hybrid SOFC–GT power system has been developed and the thermal efficiency of the system can be enhanced upto 70-85%. This paper focuses of thermodynamic analysis of an internal reformed solid oxide fuel cell which is integrated with the gas turbine cycle to form a hybrid power generation system for an unmanned aerial vehicle (UAV) with a long range. Thermodynamic 1st and 2nd law, parametric analysis has been carried out and the effect of various parameters such as compressor pressure ratio, turbine inlet temperature, air flow rate has been examined. In order to validate the results, present work has been compared with the available literature and it shows good agreement.
2017-09-19
Technical Paper
2017-01-2124
Violet Leavers
Within the aviation industry the analysis of wear debris particles recovered from magnetic plugs and lubricating fluids is an essential condition monitoring tool. However, in large organisations, high staff turnover in remote work environments often leaves dangerous gaps in on-site support and background knowledge. The current work seeks to bridge those gaps by developing interactive software dedicated to wear debris particle classification, root cause diagnosis and serviceability prognostics. During the research several hundred wear debris particle images were collected, analysed and classified. Each image was analyzed by a number of experts and at each stage of the analysis the experts were questioned about the knowledge and experience used to make their diagnoses and prognoses. The end result is the compilation of an extensive knowledge base representing the combined expertise of a number of highly trained engineers, each with decades of hands-on experience.
2017-09-17
Journal Article
2017-01-2480
Roberto Dante, Andrea Sliepcevich, Marco Andreoni, Mario Cotilli
Tin sulfides (SnS, Sn2S3, and SnS2, represent a safer and greener alternative to other metal sulfides such as copper sulfides, etc. Their behavior is usually associated to that of solid lubricants such as graphite. A mixture of tin sulfides, with Sn having different oxidation states, has been characterized by scanning electron microscopy and by thermal gravimetric analysis (TGA). In order to investigate the effect of tin sulfides upon two crucial friction material ingredients, two mixtures were prepared: the former was made by mixing tin sulfides with graphite and the latter was made mixing tin sulfides with a straight novolak. They were analyzed by TGA and differential thermal analysis (DTA) in nitrogen air. Almost no interference was detected between tin sulfides and graphite in air since the thermal oxidation of the tin sulfides and that of graphite were separated by more than 200°C.
2017-09-17
Technical Paper
2017-01-2490
Qianjin Yang, Baozhi Zhang, Kangrong Ding, Liqiang Song
A brake disc is one of the most critical components in modern vehicle’s brake systems, and is always among the top customer concerns of safety and conformability. To meet the challenges in its applications, strict validation of the brake disc performances in the development process is necessary. These performances include its ability to sustain its designed functions under extreme loading conditions; the high-cycle and low-cycle durability under repeated thermal and/or mechanical loading; and fine NVH performances and environment friendly. Finite element analysis, one of the most popular CAE tools, has become a great validation tool in the brake disc development process. In this paper, a disc brake system under a constant braking torque is analyzed using finite element method, in which the stress and strain in the ventilated brake disc employed are the major concern.
2017-09-17
Technical Paper
2017-01-2489
Christian Ball, Li Lee, Weicherng Wang
The standard method for using FEA to predict and eliminate brake squeal has been to use complex eigenvalue analysis (CEA). Energy flow analysis has been adapted for use with FEA for brake squeal as an alternate mechanism for squeal prediction. This paper demonstrates an implementation of energy flow analysis with commercially available FEA software. The approach leverages the ability of the Abaqus FEA solver to obtain a quasi-static, pre-loaded brake model, as well as Abaqus’ eigenvalue extraction algorithms to create a modal space for energy flow calculations. This modal space, as well as the pre-loaded stiffness matrix, is then utilized to calculate energy flow values between nearby system modes. Three case studies are presented that compare the results of CEA and energy flow to different systems and countermeasures adopted to reduce noise occurrence in physical testing.
2017-09-17
Technical Paper
2017-01-2492
Dejian Meng, Ziyi Wang, Lijun Zhang, Zhuoping Yu
Supposed disc surfaces have initial disc thickness variation (DTV) with 2 order sine function characteristics, a FE model of ventilated disc brake for transient thermomechanical coupling simulation was established. With the distribution of the temperature, the normal stress and the elastic deformation on disc surfaces for the evaluation, the influences of the initial DTV and its direction and maximum on thermomechanical coupling characteristics were analyzed. The simulation results show that the temperature, the normal stress and the thickness variation have a 2 order sine function characteristic in circumferential direction, which is the most important difference between the thermomechanical coupling characteristics with and without the initial DTV. The 2 order sine function distribution in circumferential direction is related with the initial DTV direction and tendency.
2017-09-17
Technical Paper
2017-01-2494
Severin Huemer-Kals, Manuel Pürscher, Peter Fischer
Complex Eigenvalue Analysis (CEA) is widely established as a mid- to high-frequency squeal simulation tool for automobile brake development. As low-frequency phenomena like creep groan or moan become increasingly important and appropriate time-domain methods are presently immature and expensive, some related questions arise: Is it reasonable to apply a CEA method for low-frequency brake vibrations? Which conditions in general have to be fulfilled to evaluate a disk brake system’s noise, vibration and harshness (NVH) behavior by the use of CEA simulation methods? Therefore, a breakdown of the mathematical CEA basis is performed and its linear, quasi-static approach is analyzed. The mode coupling type of instability, a common explanation model for squeal, is compared with the expected real world behavior of creep groan and moan phenomena.
2017-09-17
Technical Paper
2017-01-2485
Tarun Teja Mallareddy, Peter Blaschke, Sarah Schneider, Daniel J. Alarcón
Brake squeal is an NVH issue experienced by brake systems and vehicle manufacturers for decades. This leads to customer dissatisfaction and the questioning of quality of the brake system. Advanced testing tools, design modification, dynamometer testing, vehicle validation etc., are performed to study, analyze and eliminate this problem. But, still it continues to exist. One of the most important reasons is the complexity of the brake pad which leads to its non-linear properties. Therefore, it is imperative to understand the behavior of the brake pad, in terms of its dynamic properties (eigenfrequencies, damping and mode shapes), under varying boundary conditions. Experimental Modal Analysis (EMA) is used to study the dynamic properties of any structure and is generally performed under free-free boundary conditions. An approach to study brake pads under pressure condition is a step towards reality, as brake pads squeal only during braking events.
2017-09-17
Technical Paper
2017-01-2509
Guirong Zhuo, Ruonan Xue, Subin Zhang, Cheng Wu, Kun Xiong
Abstract Electromechanical Braking System (EMB) stops the wheel by motor and related enforce mechanism to drive braking pads to clamp the friction plate. It is compact in sized as well as faster in response, which solves the issue of potential leakage and slows response of traditional hydraulic brake system. The institutions at home and abroad have put forward all kinds of new structural schemes of EMB. At present, there are various EMB structural schemes, but the analysis and evaluation of these schemes are relatively few. In this paper, on the basis of a large number of research, the EMB actuator is modular decomposed according to function ,then the parametric 3D model library of each function module is established. According to brake requirements of the target vehicle, a development platform is set up to match EMB actuator structure scheme quickly.
2017-09-17
Journal Article
2017-01-2527
Dejie Huang, Xu Zhou, Peiqing Qian, Chao Wen, Yu Liu
Abstract The seal structure and key parameters of wheel bearing were introduced. Research on sealing failure diagnosis, abrasive scratch analysis, residual interference, and abrasion reconstruction was carried out for a typical seal structure. Based on these methods of scientific failure analysis, eight causes of seal failure were summarized systematically, which were important for the guidance of seal design and failure analysis of wheel bearings.
Viewing 1 to 30 of 8137