Refine Your Search

Topic

Author

Affiliation

Search Results

Technical Paper

Wall Heat Flux on Impinging Diesel Spray Flame: Effect of Hole Size and Rail Pressure under Similar Injection Rate Condition

2020-10-30
2020-32-2313
The fuel economy of recent small size DI diesel engines has become more and more efficient. However, heat loss is still one of the major factors contributing to a substantial amount of energy loss in engines. In order to a full understanding of the heat loss mechanism from combustion gas to cylinder wall, the effect of hole size and rail pressure under similar injection rate conditions on transient heat flux to the wall were investigated. Using a constant volume vessel with a fixed impingement wall, the study measured the surface heat flux of the wall at the locations of spray flame impingement using three thin-film thermocouple heat-flux sensors. The results showed that the characteristic of local heat flux and soot distribution was almost similar by controlling similar injection rate except for the small nozzle hole size with increasing injection pressure.
Technical Paper

Investigations on NOx and Smoke Emissions Reduction Potential through Diesel-Water Emulsion and Water Fumigation in a Small Bore Diesel Engine

2020-10-30
2020-32-2312
In the present work, a relative comparison of addition of water to diesel through emulsion and fumigation methods is explored for reducing oxides of nitrogen (NOx) and smoke emissions in a production small bore diesel engine. The water to diesel ratio was kept the same in both the methods at a lower concentration of 3% by mass to avoid any adverse effects on the engine system components. The experiments were conducted at a rated engine speed of 1500 rpm under varying load conditions. A stable water-diesel emulsion was prepared using a combination of equal proportions (1:1 by volume) of Span 80 and Tween 80. The mixture of Span 80 in diesel and Tween 80 in water was homogenized using an IKA Ultra Turrax homogenizer with tip stator diameter 18mm at 5000 rpm for 2 minutes. The water-in-diesel emulsions thus formulated were kinetically stable and appeared translucent. No phase separation was observed on storage for approximately 105 days.
Technical Paper

Enclosure-In-Chamber Setup to Achieve Near-Zero Background Concentrations for Brake Emissions Testing

2020-10-05
2020-01-1634
Measuring brake emission is still a challenging non-standardized task. Extensive research is ongoing. Updates of work in progress are presented at SAE Brake Colloquium and PMP meetings. However, open items include how to achieve lower background concentration and how to design the brake enclosure. A low background concentration is essential as brake events are short and some emit in the range of reported background levels. Hence these emissions are difficult to distinguished from the background level. Even more critical, a high background concentration can result in a wrong particle number emissions value, either overestimated, background counted as emissions, or underestimated, background level subtracted, and low emission events no longer detected and counted. However, reducing the background level to less than 100 #/cm³ appeared to be quite challenging.
Technical Paper

Rust is not a Must. Improvement of Discs Corrosion Resistance by Tuning of Cast Iron Alloying Elements and Microstructure.

2020-10-05
2020-01-1624
In the last decade, the increasing electrification of road transports has stimulated the look for new braking systems with a high corrosion resistance. This resulted in a fervent research activity behind the development of disc brakes with a reduced corrodibility under demanding tribocorrosive environments. Despite of this, a significant reduction of the cast iron disc corrodibility can be achieved not only by developing variously coated rotors, but also by modulating the intrinsic corrodibility of iron. This can be done by and ad-hoc refining of the cast iron: a) alloying elements concentration; b) microstructure; and c) carbon content and morphology. At this regard, in this contribution, the corrosion properties of a representative ensemble of cast iron specimens are reviewed.
Technical Paper

Anodization: Recent Advancements on Corrosion Protection of Brake Calipers

2020-10-05
2020-01-1626
Brake calipers for high-end cars are typically realized using Aluminum alloys, with Silicon being the most common alloying element. Despite the excellent castability and machinability of AlSix alloys, anodization is often necessary in order to provide to AlSix components the required corrosion resistance or when the braking system has to withstand to severe chloride-rich environments [1]. Even if the anodization process is known for almost 100 years, a continuous research and process optimization can lead to the development of anodic layers with enhanced morphological and electrochemical properties, which enable a prolonged resistance of calipers under endurance corrosive tests (e.g. >1000hours Neutral Spray Tests).
Technical Paper

Wear Evaluation of Niobium-Added Cast Iron for Brake Disc and Drum Applications

2020-10-05
2020-01-1627
Grey cast iron alloys for brake drum and brake disc applications are being developed with niobium additions and a range of equivalent carbon for commercial, passenger vehicle, and performance applications. The benefit of niobium in cast iron is based on the contribution of strength by matrix refinement for a given carbon equivalence that may permit the direct improvement of wear improvement or allow for an increase in carbon equivalence for a given strength. Proper carbon equivalency and pearlite stabilization contribute to an improved pearlite structure with an optimized distribution of graphite. These structures, when refined with niobium, demonstrate increased service life and reduced wear relative to their niobium-free equivalents as measured by lab dynamometer testing and by on-vehicle testing in passenger bus fleets.
Technical Paper

A Generic Testbody for Low-Frequency Aeroacoustic Buffeting

2020-09-30
2020-01-1515
Raising demands towards lightweight design paired with a loss of originally predominant engine noise pose significant challenges for NVH engineers in the automotive industry. From an aeroacoustic point of view, low frequency buffeting ranks among the most frequently encountered issues. The phenomenon typically arises due to structural transmission of aerodynamic wall pressure fluctuations and/or, as indicated in this work, through rear vent excitation. A possible workflow to simulate structure-excited buffeting contains a strongly coupled vibro-acoustic model for structure and interior cavity excited by a spatial pressure distribution obtained from a CFD simulation. In the case of rear vent buffeting no validated workflow has been published yet. While approaches have been made to simulate the problem for a real-car geometry such attempts suffer from tremendous computation costs, meshing effort and lack of flexibility.
Technical Paper

A Simulation Study Assessing the Viability of Shifting the Location of Peak In-Cylinder Pressure in Motored Experiments

2020-09-27
2020-24-0009
Some hybrid powertrains utilize an engine to benefit from the power density of the liquid fuel while the electric machine; for transient needs, for very low loads and where legislation prohibits any gaseous and particulate emissions. Consequently, the operating drive cycle of an engine also shifted from its conventional, broad range of speed and load to a narrower operating range of high thermal efficiency. This requires a drastic departure from conventional engine architecture, meaning that analytical models used to predict the behaviour of the engines early in the design cycle are no longer always applicable. Friction models are an example of sub-models which struggle with previously unexplored engine architectures. The pressurized motored method has proven to be a simple experimental setup which allows a robust FMEP determination against which engine friction simulation can be fine-tuned.
Technical Paper

Experimental Investigation on the Effects of Cooled Low Pressure EGR and Water Injection on Combustion of a Turbocharged GDI Engine

2020-09-27
2020-24-0003
This work focuses on the effects of cooled Low Pressure EGR and Water Injection observed by conducting experimental tests consisting mainly of Spark Advance sweeps at different cooled LP-EGR and WI rates. The implications on combustion and main engine performance indexes are then analysed and modelled with a control-oriented approach, showing that combustion duration and phase and exhaust gas temperature are the main affected parameters. Results show that cooled LP-EGR and WI have similar effects, being the associated combustion speed decrease the main cause of exhaust gas temperature reduction. Experimental data is used to identify control-oriented polynomial models able to capture the effects of LP-EGR and WI on both these aspects. The limitations of LP-EGR are also explored, identifying maximum compressor volumetric flow and combustion stability as the main ones.
Technical Paper

Experimental studies on weldability of Oil Hardening Non Shrinking die steel

2020-09-25
2020-28-0424
The Oil Hardening Non Shrinking (OHNS) die steel refers to a variety of carbon and alloy steels that are particularly well-suited for making tools. Though these steels are weldable, there is risk of crack formation. But, this can be avoided with convinced specifications like pre heating, proper choice of electrode etc., In the present work, OHNS die steel is welded with three different electrodes. The chosen electrodes are mild steel electrode, E312-16 chromium based electrode and E-NiCrFe-3 nickel based electrode. The OHNS steel is welded with these three electrodes and the welded specimens were examined for hot cracking tendency and mechanical properties of the joint. The hot cracking tendency was assessed by Houldcroft`s weldability test (Fishbone test). All the three electrodes proved the good results in terms of hot crack resistance and the specimen welded with E312-16 chromium based electrode provides good mechanical properties.
Technical Paper

Design and analyse of air intake in manifold student formula vehicle

2020-09-25
2020-28-0485
The SAE organization constrained a rule to place a restrictor of diameter 20mm in between the throttle body and the engine inlet . The restrictor is an component which reduces and regulates the mass flow of air into the engine inlet. For this a venture nozzle will be used as a restrictor in vehicle to decrease the air pressure and increase the velocity in the intake manifold . The aim of our proposed work is to minimize the pressure drop by changing the convergent and divergent angles in the restrictor. For this by using solidworks sixteen various models with convergent angle as 11,13,15,17 degrees and divergent angle as 3,5,7,9 degrees was designed and analysed using CFD fluent in ansys work bench. In this 13 degree as convergent and 5 degree as divergent model was found to have laminar air flow through out with optimum pressure drop. The plenum is a large duct which equalise the pressure drop caused by restrictor in order to improve the efficiency of engine.
Technical Paper

Modeling and Simulation of A Fighter Aircraft Cabin Temperature Control System Using Amesim

2020-09-25
2020-28-0497
Environmental Control System (ECS) of an aircraft is a complex system which operates classically in an air standard refrigeration cycle. ECS controls the temperature, pressure and flow of supply air to the cockpit, cabin or occupied compartments. The air cycle system of ECS takes engine bleed air as input. Parameters like bleed air pressure and temperature, mass flow, the external factors like ambient temperature, pressure, and aircraft attitude affect the performance of ECS to a large extent especially during transient. So, it is very important to consider the transient characteristics of these parameters in the design stage itself in order to ascertain the dynamic response of the system. This paper explains in detail the importance of transient input characteristics during the detailed design of ECS. A typical temperature control scheme for combat aircraft ECS has been studied and modeled in LMS AMESim.
Technical Paper

Optimization and experimental analysis of Magnesium alloy (AZ91E) hybrid nano composite by drilling operation

2020-09-25
2020-28-0509
The usage of AZ91E series magnesium alloy material increases in the field of automobile, aero space and structural applications because of its enhanced mechanical properties, light weight and good machinability characteristics. The present investigation is to optimize the drilling process parameters of magnesium alloy (AZ91E) hybrid nano composite consisting of chopped basalt fiber (9wt%) and SiCnp(7.5wt%) fabricated by vacuum stirring technique.. AZ91E hybrid nano composite is drilled by M-Tab vertical machining centre equipped with CNC under dry state (without coolant). The dry state drilling operation was performed by HSS tool with varied input parameters like drill diameter (4mm, 6mm, 8mm and 10mm), drill diameter prevailing with spindle speed, feed rate and constant depth of cut. The effect of machining time, metal removal rate and surface roughness is evaluated and optimum level of drilling parameters is determined through taguchi technique.
Technical Paper

Effect of Shot Peening Exposure Time on Mechanical Behavior of Al 7075-T6 Alloy

2020-09-25
2020-28-0430
This investigation addresses the effect of exposure time applied through shot peening as one of the severe plastic deformation technique on mechanical behavior of Al 7075-T6 alloy. Shot peening induces hardened layer in the surface region due to work-hardening effect by shot peening. The specimen shot peened for 105 s (SP105) exhibited highest values of tensile strength (591 MPa), yield strength (550 MPa) and surface hardness (265 VHN) as compared with untreated specimen with 568 MPa, 504 MPa and 184 VHN respectively. The increment in tensile properties are due to rapid improvement in the surface work-hardening by virtue of peening treatment with 105 s duration. In contrast, the shot peened alloy exhibited lower percentage elongation and higher surface roughness as compared with untreated one. The surface morphology and roughness studies before and after the treatment analyzed by suitable characterization.
Technical Paper

Experimental Study on Influence of Iron Oxide Nano particles on Characteristics of a Low Heat Rejection Diesel Engine Operated with Methyl Esters of Waste Cooking Oil

2020-09-25
2020-28-0412
In this study, an attempt was made to investigate the influence of Iron Oxide Nano particle on the performance, emission and combustion characteristics of Low Heat Rejection (LHR) diesel engine operated with methyl esters of Waste Cooking Oil (WCOME). In the first phase of the work, single cylinder, direct injection diesel engine test rig was developed and tested for its baseline readings with diesel at different power output. In the second phase of the work, test engine was operated with WCOME and tested for its characteristics. Test engine was modified to operate in the LHR mode in the third phase of the work. Engine's cylinder head, valves and piston crown were coated with lower thermal conductivity materials namely, 200 microns of Yttrium Stabilized Zirconia & 100 microns of Nickel, Chromium and aluminium alloys. LHR engine was tested with WCOME and tested for its characteristics in the fourth phase.
Technical Paper

Ergonomic study of occupant seating using near-vertical posture for shared mobility applications

2020-09-25
2020-28-0519
Transportation system is at the brink of revolution and many new ways of mobility are arising in the market to ease the pressure on the established transportation infrastructure. Many companies and government around the world are exploring innovative options in the space of shared mobility to reduce the overall carbon footprint. To expedite the adoption of shared mobility based travelling options in India, it is necessary to make such options comfortable and cost-effective. To make the mobility option cost-effective, it is important to comfortably allow as many passengers per vehicle foot-print as possible. This paper aims to evaluate a novel method of occupant seating to maximize the number of passages the vehicle cabin can accommodate. Since shared mobility options are used for a short duration of commute, the comfort of the seat can be compromised for increasing the no. of occupants. This paper studies the relation between occupant comfort and the inclination of seat cushion.
Technical Paper

Experimental and Numerical Investigation of Contact Pressure Existance in Sealing Structure

2020-09-25
2020-28-0343
Sealing is one of the important components in automotive and aerospace industry. The primary function of lip seal is to protect contamination and retaining the lubricant. This investigation relates to study of contact pressure existence on dynamic sealing. Sealing for steering intermediate shaft requires sliding motion between shaft and seal as well as protection of lubricant from contamination and retention. Contact pressure analysis of Steering intermediate shaft with hyper elastic rubber seal is done at static as well as sliding condition using ABAQUS. Experiments were also conducted to check contact pressure between seal and shaft by using Fuji-pressure film sensor. The result from CAE analysis was compared with experimental data. This analysis of contact pressure helps to support enough interference between seal and shaft with satisfies the need of sealing as well as sliding in intermediate shaft.
Technical Paper

The effect of TiB2 on mechanical and microstructural properties of AZ91 matrix composites manufactured by cold chamber die casting process

2020-09-25
2020-28-0425
In these work AZ91 magnesium matrix composites reinforced with two weight fractions (5 and 10 wt. %) of TiB2 particulates were fabricated by cold chamber die casting process technique. The microstructure, density, hardness, mechanical properties of the specimens was investigated. Microstructure studies showed that fairly uniform distribution of reinforcements was achieved up to the weight fraction studied. As compared to base alloy AZ91, the hardness and tensile strength considerably increased with increasing reinforcement content. The presence of TiB2 particles improved the hardness around 24.4 %, compressive strength around 67.2% and the yield strength around 20%. The enormous amount of increment in the compressive strength due to the dislocation density created by the difference in thermal properties of matrix and composites and also due to the micro-pores presence in the composite.
Technical Paper

Comparative Studies on Conventional groove SMA and GMA welds of Dissimilar 304LN ASS and HSLA Steels.

2020-09-25
2020-28-0405
Dissimilar metal welds (DMWs), between austenitic stainless steel (ASS) and micro-alloyed high strength low alloy steel (HSLA), are used in high temperature applications in power stations and petrochemical plants. The gas metal arc welding (GMAW) has surpassed the shielded metal arc welding (SMAW) process due to its advantages of producing fast, long, clean continuous weld at any position [1-4]. A studies on mechanical and metallurgical properties of conventional V-groove SMAW and GMA Welding of dissimilar 20 mm thick 304LN ASS and micro alloyed HSLA steel plate were carried out by using austenitic E308L- 15 electrode with gas tungsten arc welding (GTAW) root pass. The tensile (axial and all-weld) properties, hardness and microstructure of the weld and HAZ are analyzed.
Technical Paper

Investigations on the Effect of Synchronizer Strut Detent Groove Profile on Static and Dynamic Gear Shift Quality of a Manual Transmission

2020-09-25
2020-28-0319
Automotive manufacturers are constantly working towards enhancing the driving experience of the customers. In this context, improving the static and dynamic gear shift quality plays a major role in ensuring a pleasant and comfortable driving experience. Moreover, the gear shift quality of any manual transmission is mainly defined by the design of the synchronizer system. In the present work, the static and dynamic shift quality of a 300 Nm manual transmission is analyzed with different synchronizer sleeve strut detent profiles. The synchronizer sleeve strut detent groove profile play a vital role in defining the performance of the synchronizer system by generating the minimum required pre-synchronization force. This force is important to move the outer synchronizer ring (blocker ring) to the required index position and to wipe-out the oil from the conical friction surfaces to build rapid high cone torque.
X