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Model Predictive Control of an Air Path System for Multi-Mode Operation in a Diesel Engine

Garrett Advancing Motion-Paul Dickinson, Jaroslav Pekar, MinSeok Ko
Hyundai Motor Group-Buomsik Shin, Yohan Chi, Minsu Kim
  • Technical Paper
  • 2020-01-0269
To be published on 2020-04-14 by SAE International in United States
A supervisory model predictive control system is developed for the air system of diesel engine. The diesel air system is complicated, composing of many components and actuators, with significant nonlinear behavior. Furthermore, the engine usually often operates in various modes, for example to activate catalyst regeneration like LNT or DPF. Model predictive control (MPC) is based on a dynamical model of the controlled system and it features predicted actuator path optimization. MPC has been previously successfully applied to the diesel air path control problem, however, most of these applications were developed for a single operating mode (often called normal operating mode) which has only one set of high-level set point values. In reality, each engine operating mode requires a different set of set point maps in order to meet the various system requirements such as, HP-EGR modes for cold start purposes, heat-up modes for after-treatment conditioning, rich operation for catalyst purging and normal modes. Air mass and its composition requirement are heavily depending on each specific mode. This large array of mode specific set points…
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An Experimental Investigation of In-cylinder Flow Motion Effect on Dual-fuel Premixed Compression Ignition Characteristics

Hyundai Motor Group-Hyunsung Jung, Hyounghyoun Kim, Yohan Chi
Seoul National University-Sanghyun Chu, Hyungjin Shin, Kihong Kim, Sunyoung Moon, Kyoungdoug Min
  • Technical Paper
  • 2020-01-0306
To be published on 2020-04-14 by SAE International in United States
The combustion process using two fuels with different reactivity, known as dual-fuel combustion or RCCI is mainly studied to reduce emissions while maintaining thermal efficiency. Many studies have proven that dual-fuel combustion has a positive prospect in future combustion to achieve near-zero engine out emissions with high indicated thermal efficiency. However, a limitation on high-load expansion due to the higher maximum in-cylinder pressure rise rate (mPRR) is a main problem. Thus, it is important to establish the operating strategy and study the effect of in-cylinder flow motion with dual-fuel combustion to achieve a low mPRR and emissions while maintaining high-efficiency. In this research, the characteristics of dual-fuel combustion on different hardware were studied to verify the effect of the in-cylinder flow motion on dual-fuel combustion. To see such an effect, different head types (swirl and tumble) were used with different combustion chamber shapes (conventional vs bathtub). The higher thermal efficiency with swirl motion on low load combustion was shown with stable combustion due to the faster combustion occurred by air-fuel mixing of diesel fuel by…
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A Study of Combustion Control Parameter Optimization in a Diesel Engine Using Cylinder Pressure

Hyundai Motor Co.-Buomsik Shin, Insoo Jung, Soonchan Pyo, Yohan Chi
Published 2014-04-01 by SAE International in United States
In diesel engine development, fuel consumption, emissions and combustion noise have been main development objectives for fuel economy, low emissions and NVH. These main objectives can be achieved with advanced engine technologies. As electronic actuating systems are widely applied on diesel engines, elaborate control is required. This is because the main development targets are greatly affected by engine control parameters but frequently have a trade-off relationship. Therefore, the optimization of combustion control parameters is one of the most challenging tasks for improvement. As an efficient method, the DOE methodology has been used in engine calibration. In order to develop a mathematical model, the input and output values must be measured. Unlike other variables, combustion noise has been continually reported to have better indication method in simplified way. In this paper, advanced noise index from cylinder pressure signal is applied on engine test. Its interactive relationship with fuel economy and emissions is explored and analyzed. The sensitivity of fuel consumption and emissions to combustion noise is quantified in a 1.6 passenger diesel engine. This analysis also…
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Diesel/Gasoline Dual Fuel Powered Combustion System based on Diesel Compression Ignition Triggered Ignition Control

Hyundai Motor Company-Dae Choi, Hyunsung Jung, Yohan Chi
Southwest Research Institute-Shinhyuk Joo
Published 2013-04-08 by SAE International in United States
The author's new approach, diesel and gasoline dual fuel powered combustion system based on diesel CI triggered ignition control, provides not only how key ideas extracted from LTC concept could be established in a small bore HSDI turbocharged diesel engine but also which mechanism works to bring almost same benefits as we have experienced in both conventional diesel combustion and LTC based advanced combustion systems like HCCI, PCCI and PPCI combustions.The combustion system presented in the paper physically combines both mixing controlled diesel compression ignition combustion and gasoline premixed charge combustion in one power generation cycle. Gasoline fuel in the system is provided by the conventional gasoline PFI system firstly into the cylinder in which premixed charge spreads out. In compression stroke, the exact amount of diesel fuel is injected into the highly diluted EGR ambient with premixed gasoline charge. As a consequence, the mixing controlled diesel ignition is followed by gasoline flame propagation and it generates demand power in the expansion stroke.Dual fuel powered combustion system has been implemented in 1.6 liter VGT diesel…
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Technologies for Improved Emission Potential in a Small Displacement Volume Passenger Diesel Engine

Hyundai Kia Motor R&D Division-Buomsik Shin, Haengpyo Heo, Hyeungwoo Lee, Yohan Chi
Published 2009-04-20 by SAE International in United States
Diesel engine has been attractive for its high thermal efficiency with the large penetration into the passenger car. Main progress of diesel engine is in the emission control and performance potential. New technologies are introduced to cope with the requirement toward cleaner engine. Although new technologies are effective in emission reduction, their application should be approached carefully because they have both positive and negative effect on fuel economy and cost. Therefore, it is important to understand the characteristics of the individual technology and optimize efficiently. It is more required in the small displacement engine. In this paper, several technologies are presented and their characteristic behaviors are investigated for a small displacement volume passenger diesel engine. Thereby, emission potential is improved to comply with upcoming emission standards.
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Effects of VGT and Injection Parameters on Performance of HSDI Diesel Engine with Common Rail FIE System

Hyundai Motor Company-Yohan Chi, Jaehoon Cheong, Changho Kim, Kyuhoon Choi
Published 2002-03-04 by SAE International in United States
Recently, high speed direct injection (HSDI) diesel engines are rapidly expanding their application to passenger cars and light duty commercial vehicles in western European market and other countries such as Korea and Japan. These movements are strongly backed by the technological innovations in the area of air charging and high pressure fuel injection systems. Variable geometry turbine (VGT) turbocharger, which could overcome the typical weak point of the existing turbocharged engine, and the common rail fuel injection system, which extended the flexibility of fuel injection capability, became two of the most frequently referred keywords in recent HSDI technology. In this paper some aspects of VGT potential as a full load torque and power modulator will be discussed. Possibility to utilize the portion of full load potential in favor of part load emissions and fuel economy will be investigated. A strategy of boost pressure control will be suggested as an attempt to fully utilize the flexibility of VGT in optimizing combustion efficiency. In the later part, the impact of fuel injection parameters such as rail pressure,…
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Measurement of Droplet Size Distribution of Transient Diesel Spray

Seoul National Univ.-Yohan Chi, Eungseo Kim
Published 1993-11-01 by SAE International in United States
To clarify the atomization characteristics of transient diesel spray droplet size distribution of spray was measured and Sauter mean diameter (SMD) was also calculated using the optical method based on Fraunhofer diffraction theory at different locations along the spray axis and at different time from the start of injection. To investigate the effects of various operating parameters on drop sizes the injection pressure and the density of gas phase into which spray injected was varied.At each location of spray the timewise measurement of SMD showed its peak value at initial stage and gradually decreased to reach an almost constant value noting that the fully developed spray and droplet - gas equilibrium were being approached. This indicated that the atomization of spray was not a process that ended as the liquid left the nozzle exit but one that continued in time and space. The high SMD value in the initial stage suggested that the leading edge of spray was mainly composed of larger droplets than the trailing spray. This was mainly due to the collision and…
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