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Experimental study on a turbine housing with inner insulation structure has been conducted for rapid light-off of the catalyst unit, which is located at the downstream side of turbochargers. The turbine housing with feasible inner-insulation structures has been designed and prototyped. It is referred to as the inner-insulated turbine housing. The concept of inner-insulation structures is a combination of sheet metals and insulators. The turbine housing was built using metal additive manufacturing with powder bed fusion technique. The gas stand test demonstrates the inner-insulated turbine housing under cold start-up with high temperature and idle condition to evaluate the time reduction for activation of the catalyst unit. To acquire the thermal and flow characteristic of the catalyst element, sheathed thermocouples were installed in the catalyst element.

Upcoming, increasingly stringent greenhouse gas (GHG) as well as emission limits demand for powertrain electrification throughout all vehicle applications. Increasing complexity of electrified powertrain architectures require an overall system approach combining component technology with integration and industrialization requirements when heading for further significant efficiency optimization of the subsystem internal combustion engine. The requirements on the combustion engine in hybrid powertrains are quite different to those in a conventional powertrain solution. Next-generation hybrid engines, with brake thermal efficiency (BTE) targets starting from 42-43% and aiming for 45% and above within the product lifecycle, require a re-thinking of the base engine architecture of current modular engine platforms. At the same time focus on the product cost and minimized additional investment demand reuse of current production, machining and assembly facilities as far as possible.

Based on the technology of the order tracking and extraction, a software for the modulation of sound quality of automotive order sound is developed in this paper. The order analysis, the amplitude modulation of order sound in specific speed range and the calculation of the functional expression of the order sound amplitude are integrated in this software. Furthermore, a side-valve interpolation correction algorithm (SV-ICA) is proposed to solve the problem that the smooth transition of the order sound curve at endpoints cannot be guaranteed, which would result in the appearance of abnormal noise in the modulated sounds. The application of built software in constructing the automobile sounds with the sound quality of sportiness is demonstrated.

Engine cooling systems for vehicles are used for cooling the engine fluids. The cooling system normally consists of following components: radiator, expansion tank, cooling fan, fan drive and shroud. The mounting structure for this system must be designed to withstand the loads that will be imposed by the vehicle operation which consists of stresses such as those caused by linear static and dynamic loading. Automotive industries perform various tests on vehicles in the end-user environment to reduce failures; these investigations are carried out on the design using finite element method (FEM). Finite element methods are being used routinely to analyze for structural behavior. Modeling is done with CATIA software, meshing is carried out with HYPERMESH software and solution is acquired using NASTRAN solver.

Vibration isolation performance and damping performance of the powertrain mount are important for enhancing the noise and vibration performance and the ride comfort performance of a vehicle. In the present research, attention was focused on how the ideal viscosity differs with the input frequency according to the principle of damping that occurs in hydraulic mounts. By combining the liquid column resonance phenomenon with thixotropic fluid, a technology was developed for achieving a high-level balance between low dynamic spring and high damping, which are trade-off elements in a hydraulic mount. An aqueous solution of glycol used as the base fluid was combined with clay mineral as a thixotropic agent. From the results of the viscosity measurement, it was found that as the amount of thixotropic agent added increased, the viscosity gradient increased with respect to the shear rate, but at the same time, the overall viscosity also increased.

NVH CAE is considered as one of the aspects of engine component design process. Following the best practices for CAE throughout the industry is the current trend which tend to miss the fact of improving it as per the continuously evolving component designs. Continuous improvement is necessary in existing methods and procedures to enhance CAE methodologies. Correlation of CAE models with measurement results increases stakeholders’ confidence and further allows to try out various combinations to reduce product development cycle time as well as cost. Engine components are connected with each other at periphery through bolted connection with required torque. The existing global CAE modeling practices are evolved to represent the bolt connections at the designed location. However, these practices miss the stiffness offered by the interface zone between bolts.

Today, noise perceived by the occupants is becoming an important factor driving the design standards for the design of most of the interior assemblies in an automotive vehicle. Buzz, Squeak and Rattle (BSR) is a major contributor towards the perceived noise of annoyance to the vehicle occupants. An automotive vehicle consists of many chassis assemblies which are the potential sources of BSR noise. The potential locations of critical BSR noise could be contained within such assemblies as well as across their boundaries. Engine mount design is major area where BSR noises can be heard inside cabin on various road conditions. Natural rubber is regular rubber used in engine mount applications but in this paper BSR problems are solved by changing the rubber compound i.e., NR+BR (slippery compound). Detailed case study is presented where slippery rubber compound is used which is solving BSR issue and also meeting durability targets.

The rubber mount is a key component of the electric vehicle powertrain mounting system, which can reduce the vibration of the powertrain transmitted to the vehicle body. The rubber mount with second-stage isolation means that a rubber vibration isolator is added to the metal bracket of the original rubber mount. Compared with the original rubber mount, the rubber mount with second-stage isolation has smaller dynamic stiffness and better vibration isolation performance in the high-frequency range. In this paper, the static stiffness of a rubber mount with second-stage isolation is tested, and the high-frequency dynamic characteristics of the rubber mount are calculated using the finite element simulation. According to its characteristics, an equivalent mechanical model including equivalent mass is established.

As a critical power source, the diesel engine is widely used in various situations. Diesel engine failure may lead to serious property losses and even accidents. Fault detection can improve the safety of diesel engines and reduce economic loss. Surface vibration signal is often used in non-disassembly fault diagnosis because of its convenient measurement and stability. This paper proposed a novel method for engine fault detection based on vibration signals using variational mode decomposition (VMD), K-means, and genetic algorithm. The mode number of VMD dramatically affects the accuracy of extracting signal components. Therefore, a method based on spectral energy distribution is proposed to determine the parameter, and the quadratic penalty term is optimized according to SNR. The results show that the optimized VMD can adaptively extract the vibration signal components of the diesel engine. In the actual fault diagnosis case, it is difficult to obtain the data with labels.

In the intermediate stage towards zero-emissions, use of methane-hydrogen blends in spark ignition (SI) engines could represent an attractive application. The present work investigated the relevance of empirical base rules for choosing maximum brake torque spark timing settings when using methane-hydrogen blends. A 0D/1D model was used for investigating the optimized ignition for maximizing engine output. Calibration was performed by using in-cylinder pressure data recorded on a methane fueled small size SI engine for two-wheel applications. After adaptations of the model such as valves timing, for rendering it more representative for power generation applications, the investigation was focused on how MBT spark advance was correlated to the 50% mass fraction burned mark (CA50) and peak pressure location. The fact that they were optimized for methane was found to be essential only for high concentrations of hydrogen.

Mechanical systems accomplish their tasks better when enhanced with cyber technologies. With the rapidly escalating desire for high efficiency, optimization and flexibility, these physical systems ought to be integrated with cyber technologies that enhance exhaustive manipulation of resources and productivity. The gateway for such a synergetic integration can be referred to as digitalization. Details regarding the digitization of a High-altitude Simulation chamber are discussed thoroughly in this paper. The simulation chamber was originally designed and developed as a test bench to study the characteristics of alternative fuels used in the engines of handheld tools in different altitudes and thermal conditions. It encompasses all the possible realistic temperature variations with altitude raising to 3500m above sea level.

Waste Plastics are the main barriers in the rain water percolation into the ground which enhances the improvement in the water table. This study utilizes pyrolised waste plastic oil along with diesel-bioethanol, diesel-biobutanol and butanol to fuel variable compression ratio engine. Initially, various proportions of pyrolised waste plastic oil has been blended with bioethanol-diesel blends (containing 15% of bioethanol), biobutanol-diesel blends (containing 20% biobutanol) and Biobutanol and tested for solubility under 25°C followed by property testing as per the American Society of Testing Materials. The results of the property resting are compared by considering diesel fuel as the base fuel. The results indicate that properties of the blends containing 21% of pyrolised waste plastic oil with bioethanol-diesel blends, 15% of ethanol blended with diesel fuel, and 12% of pyrolised waste plastid oil with 88% of biobutanol are closer to that of diesel fuel.

On the basis of small hybrid powertrain investigations in hand-held power tools for fuel consumption and emissions reduction, the prototype hybrid configuration of a small single-cylinder four-stroke internal combustion engine together with a brushless DC electric motor is built and measured on the testbench in terms of efficiency and emissions but also torque and power capabilities. The onboard energy storage system allows the combustion engine electrification for controlling the fuel amount and the combustion behavior while the electric motor placement instead of the pull-start and flywheel allows for start-stop of the system and load point shifting strategy for lower fuel consumption. The transient start-up results as well as the steady-state characterization maps of the system can set the limits on the fuel consumption reduction for such a hybrid tool compared with the baseline combustion-driven tool for given load cycle characteristics.

As the key assembly of new energy vehicles, the noise and vibration, and harshness (NVH) performance of integrated electric drive system directly affects the driving quality of new energy vehicles. In this paper, the vibration noise characteristic test of 3in1 electric drive system is carried out in the semi-muffler chamber. In order to compare and analyze the difference between 2in1 and 3in1 electric drive system NVH performance, the power electronics unit (PEU) in the 3in1 system was removed and placed on the ground away from the platform, and vibration noise test was carried out. In order to analyze the difference of NVH performance between 2in1 status and 3in1 status, the PEU in the 3in1 system was removed and placed on the ground far away from the bench, and the NVH test was carried out. The microphone signal at 1m position and the vibration acceleration signal of the key structural surface of the system are measured experimentally.

Eigenvalues of a simple rotating flexible disk-shaft system are obtained using different methods. The shaft is supported radially by non-rigid bearings, while the disk is situated at one end of the shaft. Eigenvalues from a finite element and a multi-body dynamic tool are compared against an established analytical formulation. The Campbell diagram based on natural frequencies obtained from the tools differ from the analytical values because of oversimplification in the analytical model. Later, detailed whirl analysis is performed using AVL Excite multi-body tool that includes understanding forward and reverse whirls in absolute and relative coordinate systems and their relationships. Responses to periodic force and base excitations at a constant rotational speed of the shaft are obtained and a modified Campbell diagram based on this is developed. Whirl of the center of the disk is plotted as an orbital or phase plot and its rotational direction noted.

Gear profile deviation is the difference in gear tooth profile from the ideal involute geometry. There are many causes that result in the deviation. Deflection under load, manufacturing, and thermal effects are some of the well-known causes that have been reported to cause deviation of the gear tooth profile. The profile deviation caused by gear tooth profile deformation due to interference-fit assembly has not been discussed previously. Engine timing gear trains, transmission gearboxes, and wind turbine gearboxes are known to use interference-fit to attach the gear to the rotating shaft. This paper discusses the interference-fit joint design and the mechanism of tooth profile deformation due to the interference-fit assembly in gear trains. A new analytical method to calculate the profile slope deviation change due to interference-assembly of parallel axis spur gears is presented.

The tensioner of the engine front end accessory drive system was taken as a study object, and the mechanical structure and working principle of the automatic tensioner were analyzed. The hysteresis behavior test of tensioner torque-angular displacement was carried out, and the effects of different excitation frequencies and excitation amplitudes on the hysteresis behavior of the tensioner were analyzed. According to the modified Dahl hysteresis model, the model parameters of the tensioner was identified. Based on the identified model parameters, the hysteresis behavior of the tensioner was calculated, and the calculation model accuracy was verified with the tested results. The influence of the hysteresis curve transition area exponent on the tensioner behavior was studied. The dynamic behavior of the engine front end accessory drive system was simulated using the simulation software.

Diesel engine is vital in the industry for its characteristics of low fuel consumption, high-torque, reliability, and durability. Existing diesel engine technology has reached the upper limit. It is difficult to break through the fuel consumption and emission of diesel engines. VVA (Variable Valve Actuation) is a new technology in the field of the diesel engines. In this paper, GT-Suite and ANN (artificial neural network) model are established based on engine experimental data and DoE simulation results. By inputting Intake Valve Opening crake angle (IVO), Intake Valve Angle Multiplier (IVAM) and Exhaust Valve Angle Multiplier (EVAM) into the ANN Model, and by using SA (simulated annealing algorithm), the optimized results of intake and exhaust valve lift under the target conditions are obtained.

The valve train is one of the most important part of engine , and its function is fresh charge inlet and exhaust exit according to order of engine based on intake and exhaust valve [1].The compression relief brake mechanism is one of the integrated brake technologies in Internal Combustion Engines (ICE) which not only reduces engine speed during downhill under overspeed condition by opening of one of the exhaust valves before the power stroke but also helpful to reduce brake pad wear by assisting in vehicle braking. The clearance between exhaust valve and piston during compression relief brake event is important aspect for overall valve train dynamic perspective. Valve motion study included this valve to piston clearance measurement in engine testing as mandate during product development phase.

Cylinder block is the bulkiest component in engine. It undergoes severe thermal and mechanical loads. Also, cylinder block is multifunctional as it includes positioning of coolant and lubrication circuit, location of coolant and oil pumps, locating cylinder head to form closed combustion chamber, locating mounting points of engine, mounting of alternator, starting motor, and AC compressors. Hence, the cylinder block design should be the strong and robust enough to handle the forces induced by combustion. Taking this requirement as the base, cylinder block is designed for Horizontal K type configuration. In this research, the mounting points of cylinder block are decided based on the imbalance forces for the configuration and from the gas pressure forces. Rigid body dynamics approach is used for locating the mounting points of engine. Topology optimization is carried out to know the location of coolant circuit.