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Technical Paper

Optimum Design Point to Recover Maximum Possible Exhaust Heat Over the Operating Range of a Small Diesel Truck Using Bottoming Rankine Cycle

2018-04-03
2018-01-1377
Abstract This paper focuses on waste heat recovery (WHR) system, which is an efficient technology to reduce fuel and vehicle carbon dioxide (CO2) emissions per kW of power produced. Wide variations of power of a vehicle make it difficult to design a WHR system which can operate optimally at all powers. The exhaust temperature from the engine is critical to design a WHR system. Higher the temperature higher will be the gain from the WHR system. However, as power drops the exhaust temperature drops which makes the WHR system perform poorly at lower powers. In this research, a small diesel truck engine was used to design a WHR system to produce additional power using a Rankine cycle (RC). The WHR system was designed at the rated power and speed of 42.8 kW and 2600 rpm, respectively. At this design point, around 15% additional power improvement was achieved resulting around 13% break specific fuel consumption reduction.
Technical Paper

Cold Start HD FTP Test Results on Multi-Cylinder Opposed-Piston Engine Demonstrating Rapid Exhaust Enthalpy Rise to Achieve Ultra Low NOx

2018-04-03
2018-01-1378
Abstract The 2010 emission standards for heavy-duty diesel engines in the U.S. have established a limit for oxides of nitrogen (NOx) emissions of 0.20 g/bhp-hr., a 90% reduction from the previous emission standards. However, it has been projected that even when the entire on-road fleet of heavy-duty vehicles operating in California is compliant with the 2010 emission standards, the upcoming National Ambient Air Quality Standards (NAAQS) requirement for ambient particulate matter and ozone will not be achieved in California without further significant reductions in NOx emissions from the heavy-duty vehicle fleet. Given this, there is potential of further reduction in NOx emissions limit standards for heavy duty engines in the US. Recently there have been extensive studies and publications focusing on ultra-low NOx after treatment technologies that help achieve up to 0.02g/bhp-hr. at tailpipe [1].
Technical Paper

Thermodynamic Cycle and Working Fluid Selection for Waste Heat Recovery in a Heavy Duty Diesel Engine

2018-04-03
2018-01-1371
Abstract Thermodynamic power cycles have been shown to provide an excellent method for waste heat recovery (WHR) in internal combustion engines. By capturing and reusing heat that would otherwise be lost to the environment, the efficiency of engines can be increased. This study evaluates the maximum power output of different cycles used for WHR in a heavy duty Diesel engine with a focus on working fluid selection. Typically, only high temperature heat sources are evaluated for WHR in engines, whereas this study also considers the potential of WHR from the coolant. To recover the heat, four types of power cycles were evaluated: the organic Rankine cycle (ORC), transcritical Rankine cycle, trilateral flash cycle, and organic flash cycle. This paper allows for a direct comparison of these cycles by simulating all cycles using the same boundary conditions and working fluids.
Technical Paper

Advanced Exergy Analysis of Air-Film Blade Cooled Marine Gas Turbine (LM2500+)

2018-04-03
2018-01-1372
Abstract Exergy analysis provides appropriate information for improvement of thermodynamic efficiency of the system focusing on system components with maximum exergy destruction. But this method lacks in showing the mutual interaction between system components on cycle performance. Hence an advanced approach i.e. Advanced Exergy Analysis’ has been adopted and discussed in present paper. Advanced exergy analysis of LM2500+, a marine gas turbine cycle adopting air-film blade cooling techniques has been reported. The advanced exergy analysis primarily focuses on categorizing the irreversibility of process components. Advanced exergy analysis identifies exergy destruction based on two different aspects: first identifying source of irreversibility and other being minimization of this irreversibility. Thus, advanced exergy analysis splits exergy destruction into endogenous and exogenous exergy destruction as well as avoidable and unavoidable exergy destructions.
Technical Paper

A Comparative Study on the Thermodynamic Analysis and Performance Characteristics of a Dedicated EGR Gasoline Engine Under Various D-lambda

2018-04-03
2018-01-1373
Abstract The concept of D-EGR (Dedicated EGR) used high EGR rate and fuel reformation to improve thermal efficiency, entire exhaust gas which supplied from a single cylinder is recirculated to the intake system and then entered into all cylinders to improve combustion. In this study, the D-EGR system is performed on a 1.5 L port fuel injection 4-cylinder gasoline engine, in comparison to the basic engine, the reduction of fuel consumption is about 20~30 g/kWh in most of the D-EGR engine operating range, a maximum 104.1 g/kWh BSFC reduction is found at 14.0bar@1800rpm, the lowest fuel consumption is decreased from 253.7 to 224.3 g/kWh by D-EGR, and the corresponding maximum brake thermal efficiency is improved from 32.6 to 36.9%.
Technical Paper

Exhaust Heat Recovery System Study in Internal Combustion Engines

2018-04-03
2018-01-1374
Abstract Strict regulations exist in different countries with respect to vehicular emissions by their respective government bodies requiring automakers to design fuel-efficient vehicles. Fuel economy and carbon emission are the main factors affecting these regulations. In this competitive industry to make fuel efficient vehicles and reduce Green House Gas (GHG) emissions in internal combustions has led to various developments. Exhaust Heat Recovery System (EHRS) plays a vital role in improving powertrain efficiency. In this system, heat rejected by the engine is reused to heat the vehicle fluids faster (for example, engine coolant, engine oil, etc.) correspondingly reducing harmful gas emissions. In internal combustion engines, generally only 25% of the fuel energy is converted into useful power output and approximately 40% of it is lost in exhaust heat.
Technical Paper

Autonomous Meshing

2018-04-03
2018-01-1386
Abstract Autonomous cars already exist, why should anybody these days spend manual time on mesh preparation? This is a task for a machine, not for a human being. In this session, we will show a one-click way to prepare the mesh for multi-bodies or complex topological objects for 3D printing. The underlying software is already in use for paint shop applications: here it prepares a body in white starting from a CAD geometry fully automatically with 5-8 hours computational time on a desktop machine, while requiring less than 15 minutes of manual work. As an input, tessellated data can be imported from several sources including automatic interfaces allowing to extract the data of multi-bodies from CAD. However, these data are often defective and not manifold. In addition, the describing surface is not represented in an exact way. The only exact information one can rely on at this stage is the position of the vertices of the mesh: they are located directly on the surface.
Technical Paper

Design of an Additive Manufactured Steel Piston for a High Performance Engine: Developing of a Numerical Methodology Based on Topology Optimization Techniques

2018-04-03
2018-01-1385
Abstract Modern high performance engines are usually characterized by high power densities, which lead to high mechanical and thermal loadings acting on engine components. In this scenario, aluminium may not represent the best choice for piston manufacturing and steel may be considered as a valid alternative. In this paper, a methodology involving optimization techniques is presented for the design of an internal combustion engine piston. In particular, a design strategy is preliminary investigated aiming at replacing the standard aluminium piston, usually manufactured by forging or casting, with an alternative one made of steel and manufactured via an Additive Manufacturing process. Three different loading conditions are employed for the topology optimizations set up. Optimization results are then interpreted and the various structural features of the steel piston are designed starting from the density distribution contour plots.
Technical Paper

The Effect of the Cell Shape on Compressive Mechanical Behavior of 3D Printed Extruded Cross-sections

2018-04-03
2018-01-1384
Abstract Additive manufacturing has been a promising technique for producing sophisticated porous structures. The pore's architecture and infill density percentage can be easily controlled through additive manufacturing methods. This paper reports on development of sandwich-shape extruded cross sections with various architecture. These lightweight structures were prepared by employing additive manufacturing technology. In this study, three types of cross-sections with the same 2-D porosity were generated using particular techniques. a) The regular cross section of hexagonal honeycomb, b) the heterogeneous pore distribution of closed cell aluminum foam cross section obtained from image processing and c) linearly patterned topology optimized 2-D unit cell under compressive loading condition. The optimized unit cell morphology is obtained by using popular two-dimensional topology optimization code known as 99-line code, and by having the same volume fraction as the heterogeneous foam.
Technical Paper

Simulation and Experimental Research on Compression Release Engine Brake Performance

2018-04-03
2018-01-1382
Abstract A 3D grid model of engine brake is established for an automobile engine. The dynamic compression release braking process is simulated by using this model. In the process of engine braking, the movement of valve and piston causes changes of the internal flow field of the engine. In this paper, the movement of valve and piston were defined by using the dynamic grid technology, so that the numerical simulation is closer to the actual situation via the updating of grid. Based on the relevant parameters of compression release engine brake (including the opening of the exhaust valve, the engine speed and the exhaust back pressure), the pressure and power of the compression release braking system were simulated under the conditions of multiple operating conditions and experimental verification was carried out. The results showed that the braking works of the compression release engine brake are mainly from the compression stroke and the exhaust stroke.
Technical Paper

Braking Force Identification of EMB Using Recursive Least-squares Method and Disturbance Observer Iteratively

2018-04-03
2018-01-1381
Abstract An identification method using recursive least-squares method with moving data window and reduced-order disturbance observer iteratively is proposed in this paper to identify fast time-varying braking force in the electronic mechanical braking system (EMB). For the type of EMB which generates braking force by balls screw and motor mounted beside wheel, the actuator will go rapidly to eliminate clearance at beginning of braking process by means of raising the braking response speed, and at the same time, increasing the motor output torque which might be far larger than required. The proposed identification method is able to identify the point of contact between the brake pads and the disk in time by identifying the change of break force, and the torque of motor will be changed in time to reduce the braking force overshoot so that brake locking is avoided.
Technical Paper

An Integrated Deformed Surfaces Comparison Based Validation Framework for Simplified Vehicular CAE Models

2018-04-03
2018-01-1380
Abstract Significant progress in modeling techniques has greatly enhanced the application of computer simulations in vehicle safety. However, the fine-meshed impact models are usually complex and take lots of computational resources and time to conduct design optimization. Hence, to develop effective methods to simplify the impact models without losing necessary accuracy is of significant meaning in vehicle crashworthiness analysis. Surface deformation is frequently regarded as a critical factor to be measured for validating the accuracy of CAE models. This paper proposes an integrated validation framework to evaluate the inconsistencies between the deformed surfaces of the original model and simplified model. The geometric features and curvature information of the deformed surfaces are firstly obtained from crash simulation. Then, the magnitude and shape discrepancy information are integrated into the validation framework as the surface comparison objects.
Technical Paper

Powertrain Cradle Verification and Validation for Bus Application Export Market

2018-04-03
2018-01-1379
Abstract To capture market share in different regions of the world, the product must fit different road profiles and operating conditions. Designing a product which suits two different markets requires many factors to be considered like the topography, driving pattern and road load profiles. This project deals with once such situations and required a stringent validation protocol which shall encompass all possible driving scenarios. The fully built vehicle is to be exported to a different market and required powertrain change and subsequently required a new cradle design. Customer usage and road profile study was carried out in the new market to estimate the percent operation in each zone i.e. good road and bad road. CAE analysis carried out to capture stress hotspots and possible failure locations. Vehicle is taken to road to measure frame acceleration at different speeds i.e. 40 kmph to 100 kmph.
Technical Paper

Atomization in High-Pressure Die Casting - Step 2 Simulation of Atomized Flow of Molten Aluminum by LES-VOF Method

2018-04-03
2018-01-1393
Abstract The atomization of molten aluminum when injected during high-pressure die casting is analyzed to determine its effect in enhancing the strength of the product being cast. In the previously reported first step of this study, molten aluminum was injected into open space and its atomization was observed photographically. Now in the second step of the study, a simulation is conducted to determine how the molten aluminum becomes atomized at the injection nozzle (gate) and how this atomized material flows and fills the cavity. A new simulation method is developed based on large-eddy simulation coupled with the volume-of-fluid method. The simulation system is verified by comparing its output with photographs taken in the first step of the study. Simulations are then conducted using an approximation of a real cavity to visualize how it is filled by the atomized molten aluminum.
Technical Paper

Research of Atomization Phenomena in HPDC-Step 1 Feature of Gas Porosity Dispersion and Photography of Atomized Flow

2018-04-03
2018-01-1392
Abstract In recent years, studies have been conducted on the relationship between the J factor, which indicates flow of molten aluminum at the time of injection, and the quality of HPDC products. The flow of molten metal at a high J factor is referred to as “Atomized Flow.” The authors and others conducted studies on the relationship between the J factor and the strength of HPDC products. An area exceeding 300MPa was found in the product produced at a high J factor corresponding to the “Atomized Flow.” The defect was less in the above-mentioned position because the gas porosity was finely dispersed. Considering that the fine dispersion of gas porosity is related to the “Atomized Flow”, pictures were taken to analyze “Atomized Flow.” The molten aluminum was ejected into an open space at a high speed and the splashed conditions were photographed. From the images taken by the pulse laser permeation, the conditions of microscopic atomized flow were observed precisely.
Technical Paper

Control of Robots Using Discrete Event System Theory

2018-04-03
2018-01-1391
Abstract In this paper, we present a project being conducted at Yalong Educational Equipment Company on control of educational robots using discrete event system theory. An educational robot is a programmable robot to be used by students for training and learning. To model a robot, we divide the robot into nine physical modules. Each module is modeled as an automaton. Parallel composition is used to obtain the entire model. The robot can be programmed to perform sequences of basic tasks. We investigate six basic tasks and use supervisors to control and achieve the tasks. Desired languages are obtained for all tasks and supervisory control theory is used to synthesize supervisors. To reduce computational complexity, modular/coordinated supervisors are used
Technical Paper

Real-Time Path Correction of an Industrial Robot for Adhesive Application on Composite Structures

2018-04-03
2018-01-1390
Abstract Due to their unique and favorable properties as well as high strength to weight ratio, composite materials are finding increasing applications in automotive, aircraft and other vehicle manufacturing industries. High demand, production rates and increasing part complexity, together with design variations require fast, flexible and fully automated assembly techniques. In automotive and aircraft manufacturing, widely used bonding and sealing processes are automated using industrial robots due to their speed, flexibility and large working volume. However, there are limitations in achieving complete automation of these processes due to the inherent inaccuracies of the industrial robots, workpiece positioning and process tolerances. Currently, the robot programs are generated in CAD/CAM environment and are adjusted manually according to the actual workpiece.
Technical Paper

Design and Prototyping of Cleaning Systems for Cylinder Head and Engine Block Conveying Lines

2018-04-03
2018-01-1387
Abstract This paper presents the design of two cleaning systems following systems engineering design approach. An in situ cleaning system was designed for removing engine oil stains and metal swarf and shavings that adhere to rollers of conveying lines which convey cylinder head as well as other heavy engine components. The other system was to clear and collect metal debris accumulated in the grooves of an engine block internal assembly line. Prototypes were fabricated for the designed cleaning equipment for further testing and assessment. In the system engineering design process, preliminary, intermediate, and detailed design were conducted following an identification of the design problem, within that process a sequence of tasks such as synthesis, analysis, prototyping, and assessment were completed.
Technical Paper

Forklift Free Operation: Compensating Downtime from Bullwhip Effect and Escalating Operation Safety

2018-04-03
2018-01-1389
Abstract The base of this project formed when trying to mitigate the loss due to downtime in logistic operation. This paper provides the insight about the interdependency of various variables that contribute toward the Bullwhip effect in Production Downtime and how the Forklift free operation can help tackle this problem and at the same time incur safe work environment. Findings from the optimization project led to the detection of the root cause of the loss of valuable time in operations related to the movement of material due to forklifts. This waste of precious movements rapidly scaled up as the material flowed through the facility and shipped out as finished goods. The concept of forklift-free operations on the production floor seemed to be a potent solution, but it came with its challenges. After SWOT analysis of the change in operations, the outcome favored the changes.
Technical Paper

Vibration Control of Active Vehicle Suspension System Using Optimized Fuzzy-PID

2018-04-03
2018-01-1402
Abstract In this paper, a fuzzy-PID controller is applied in a half vehicle active suspension system to enhance vibration levels of vehicle chassis and passenger seat. The fuzzy-PID controller consists of fuzzy and PID connecting in a series manner, the fuzzy output is considered as the PID input. Genetic Algorithm (GA) is selected to tune controller parameters to obtain optimal values that minimize the objective function. The equations of motion of five-degrees-of-freedom active half-vehicle suspension system are derived and simulated using Matlab/Simulink software. Double bumps and random road excitations are used to study the performance of suspension systems including bounce and pitch motion. The performance of the active suspension system using optimized fuzzy-PID controller is compared with conventional passive to show the efficiency of the proposed active suspension system.
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