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Training / Education

The Basics of Internal Combustion Engines

2020-11-16
In your profession, an educated understanding of internal combustion engines is required, not optional. This two-day technology survey seminar covers the most relevant topics - ranging from the chemistry of combustion to the kinematics of internal components of the modern internal combustion engine - for maximum comprehension. Attendees will gain a practical, hands-on approach to the basics of the most common designs of internal combustion engines, as they apply to the gaseous cycles, thermodynamics and heat transfer to the major components, and the design theories that embody these concepts.
Technical Paper

Study on the Effect of Air Density on the Performance of HCCI Engine Using Acetylene Gas as Fuel

2020-10-30
2020-32-2301
Owing to the combined merits of Spark ignition (SI) and compression ignition (CI) engines, homogeneous charge compression ignition (HCCI) engine technology has been receiving a greater attention in the last three decades. HCCI is a promising concept for combustion engines to reduce both emissions and fuel consumption. Utilization of different alternative fuels for HCCI engines is yet to be explored more. In this investigation, an attempt was made to use acetylene as a fuel in an HCCI engine. For this purpose, a single cylinder, four stroke, air-cooled CI engine was converted into HCCI mode. Acetylene was inducted into the intake manifold by using manifold injection technique. Air at different densities was supplied to the HCCI engine. The effects of varying air density on the performance and emission characteristics of the HCCI engine were assessed and the results are presented in this paper
Technical Paper

CFD Simulation Methodology for a Rotary Steam Expansion Piston Engine

2020-10-30
2020-32-2303
In industrial processes, combustion engines and co-generation plants, large amounts of waste heat are generated, which are often lost to the environment. The conversion of this thermal energy into mechanical work and ultimately into electrical power promises a significant improvement in energy utilization, the efficiency of the overall system and, consequently, cost-effectiveness. Therefore, the use of a Rankine Cycle is a well-established technical process. A recent research project investigates a novel expansion machine to be integrated into an RC-process to convert the heat energy into mechanical work. Primarily, the present work deals with the fluid dynamic simulation of this expander, which is based on the principle of a rotary piston engine. The aim is to develop, analyze and optimize the process and the corresponding components. Hence, a CFD model has to be built up, which should correspond as closely as possible to the requirements and geometries of the physical engine.
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

Improvement of Quasi-Steady State Heat Transfer Model for Intake System of IC Engines with Considering Backflow Gas Effect Using 1-D Engine Simulation

2020-10-30
2020-32-2315
For improving the thermal efficiency and the reduction of hazardous gas emission from IC engines, it is crucial to model the heat transfer phenomenon starting from the intake system and predict the intake air’s mass and temperature as precise as possible. Previously the authors developed an empirical equation based on an experimental setup of an intake port model of an ICE in order to be implemented into the engine control unit and numerical simulation software for heat transfer calculations. The authors developed an empirical equation based on the conventional Colburn analogy with the addition of Graetz and Strouhal numbers. Introduced dimensionless numbers were used to characterize the entrance region, and intermittent flow effects, respectively.
Technical Paper

Experimental Analysis on the Effects of Passive Prechambers on a Small 2-Stroke Low-Pressure Direct Injection (LPDI) Engine

2020-10-30
2020-32-2305
Two-stroke (2S) engines still play a key role in the global internal combustion engine (ICE) market when high power density, low production costs, and limited size and weight are required. However, they suffer from low efficiency and high levels of pollutant emissions, both linked to the short circuit of fuel and lubricating oil. Low- and high-pressure direct injection systems have proved to be effective in the reduction of fuel short circuiting, thus decreasing unburnt hydrocarbons and improving engine efficiency. However, the narrow time window available for fuel to be injected and homogenized with air, limited to few crank-angles, leads to insufficiently homogenized fuel-air mixtures and, as a consequence, to incomplete combustions. The use of prechambers can be a well-suited solution to avoid these issues.
Technical Paper

Improvement of Fuel Consumption for SI Engines by Combing with Glow Plug Heated Sub-chamber and Lean Burn

2020-10-30
2020-32-2310
Lean burn gasoline engines can achieve noteworthy fuel consumption and power output. However, when the mixture becomes lean, the ignition delay increases, and the flame propagation speed becomes slow, which lead to increase the combustion fluctuation. The glow plug is usually used to solve the cold start problem in diesel engines, where the compression temperature might not be high enough to ensure the proper ignition of the injected fuel, resulting in instability combustion and increased exhaust emissions. Based on this point, the present study intends to install a glow plug to the sub-chamber. Experiments were conducted on a modified single cylinder four-stroke CI engine (YANMAR TF120V) to operate as SI engine with a higher compression ratio compared to the conventional SI engines, 15.1:1. The engine is operated at a constant speed of 1000 rpm for different equivalence ratios with different voltage of glow plug which creates the temperature variation inside the sub-chamber.
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

Lubricating Oil Droplets from Piston Crown on Abnormal Combustion in Supercharged SI Engine

2020-10-30
2020-32-2302
In recent years, the supercharged spark ignition engine (SI engine) is spread out in the field of passenger vehicle. However, it has a problem of abnormal combustion which is called Low Speed Pre-ignition (LSPI). It is cleared gradually that the character of lubricating oil effects on LSPI behavior. The lubricating oil which has a tolerance for LSPI has been introduced already in the market nowadays. However, cause and mechanism of LSPI occurrence does not clear sufficiently. In previous conference SETC 2018, it was reported that the peculiar behavior of LSPI corresponded with behavior of lubricating oil from piston crown. This paper focuses on frequency of lubricating oil scattering from piston crown.
Technical Paper

Experimental Investigations on Evaporation Characteristics of Fuels for Low Temperature Combustion Engine Application

2020-10-30
2020-32-2317
The combustion and emission formation in the advanced low temperature combustion (LTC) engine strategies are highly sensitive to fuel molecular composition and properties. Ignition timing in LTC is primarily controlled by fuel chemical kinetics and thus, tailoring of fuel properties is required to address its limitations in-terms of lack of control on ignition timing and narrow operating load range. Utilizing fuel blends and additives such as nanoparticles are one of the promising approaches to achieve targeted fuel property. An improved understanding of fundamental processes including fuel evaporation is required owing to its role in fuel-air mixing and thereby emission formation in LTC. In the present work, evaporation characteristics of blends of commercial fuels, viz. gasoline, diesel and alternative fuels, viz. ethanol and butanol are investigated. Further, graphene based nanoadditives at 0.05 wt % in gasoline, diesel and butanol are also investigated.
Technical Paper

Free Multibody Cosimulation Based Prototyping of Motorcycle Rider Assistance Systems

2020-10-30
2020-32-2306
Due to the increasing computational power, significant progress has been made over the past decades when it comes to CAD, multibody and simulation software. The application of this software allows to develop products from scratch, or to investigate the static and dynamic behavior of multibody models with remarkable precision. In order to keep the development costs low for highly sophisticated products, more precisely motorcycle rider assistance systems, it is necessary to focus extensively on the virtual prototyping using different software tools. In general, the interconnection of different tools is rather difficult, especially when considering the coupling of a detailed multibody model with a simulation software like MATLAB Simulink. The aim of this paper is to demonstrate the performance of a motorcycle rider assistance algorithm using a cosimulation approach between the free multibody software called FreeDyn and Simulink based on a sophisticated multibody motorcycle model.
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