scholarly journals Study on Volumetric Efficiency of Four-Cycle Engine : The 3rd. Report, Effecto of the Valve Timing

1947 ◽  
Vol 13 (44) ◽  
pp. 105-127 ◽  
Author(s):  
Tuyoshi ASANUMA
Keyword(s):  
Volumetric Efficiency ◽  
Valve Timing

New Charging Model Imparting the Valve Timing for Real-Time Simulation

2009 ◽  
Author(s):  
Yuh-Yih Wu ◽  
Bo-Chiuan Chen ◽  
Chieh-Han Wu ◽  
Hsien-Chi Tsai
Keyword(s):  
Real Time ◽  
High Efficiency ◽  
Volumetric Efficiency ◽  
Valve Train ◽  
Valve Lift ◽  
Engine Control ◽  
Valve Timing ◽  
Real Time Simulation ◽  
Engine Model ◽  
Time Simulation

Engine Control Units (ECUs) are developed to manage the variable conditions in an operating engine, such as fuel injection, spark ignition, and valve timing, for achieving the goal of high performance, high efficiency and low emissions. Typically, an engine model is necessary for developing the engine control system. Most of the engine models for engine control are mean value engine model (MVEM) based on empirical volumetric efficiency to calculate the intake air flow rate. This kind of model is not able to simulate the changes of the valve, such as valve lift and valve timing. It can not be used for the engine with variable valve train (VVT). Therefore, a new method, able to inform the valve changing, is applied to adapt the new demand of engine models. The proposed engine model is similar to most current models except the charging system. The charging model is developed by using filling-and-emptying model to simulate the air exchange in the engine, including the intake and exhaust air dynamics. The flow through the valves is calculated according to the pressure drop between the cylinder and the manifold, the flow area of the valve opening and its flow coefficient. The other important feature of the proposed engine model is the capability of real time simulation. The model is verified by experimental volumetric efficiency and engine torque. Finally, a HIL (Hardware in the Loop) simulation is performed to confirm the real time simulation.

scholarly journals The Valve Timing Optimization of the Diesel Engine Based on Response Surface Methodology

2013 ◽  
Vol 1 (1) ◽  
pp. 44
Author(s):  
Jun Li ◽  
Lei Ji ◽  
Yangjiao Xu ◽  
Jinli Xie
Keyword(s):  
Response Surface Methodology ◽  
Diesel Engine ◽  
Simulation Model ◽  
Response Surface ◽  
Engine Performance ◽  
Volumetric Efficiency ◽  
Test Method ◽  
Valve Timing ◽  
Timing Optimization ◽  
Optimization Result

To study the effect of valve timing on the diesel engine performance, the simulation model of diesel engine was established with AVL BOOST and its accuracy was proved. The volumetric efficiency is one of the important indicators to evaluate engine performance. The volumetric efficiency as optimization objective and valve timing were optimized and discussed by using Box-Behnken test method and the response surface methodology. Optimization result shows that volumetric efficiency of the diesel engine can been increased by 6.42% under rated speed.

Physically-Based Volumetric Efficiency Model for Diesel Engines Utilizing Variable Intake Valve Actuation

2011 ◽  
Author(s):  
Lyle Kocher ◽  
Ed Koeberlein ◽  
D. G. Van Alstine ◽  
Karla Stricker ◽  
Greg Shaver
Keyword(s):  
Diesel Engine ◽  
Fuel Injection ◽  
Operating Conditions ◽  
Volumetric Efficiency ◽  
Intake Valve ◽  
Valve Timing ◽  
Tuning Parameters ◽  
Wide Range ◽  
Physically Based ◽  
Valve Actuation

Advanced diesel engine architectures employing flexible valve trains enable emissions reductions and fuel economy improvements. Flexibility in the valve train allows engine designers to optimize the gas exchange process in a manner similar to how common rail fuel injection systems enable optimization of the fuel injection process. Modulating valve timings directly impacts the volumetric efficiency of the engine. In fact, the control authority of valve timing modulation over volumetric efficiency is three times larger than that due to any other engine actuator. Traditional empirical or regression-based models for volumetric efficiency, while suitable for conventional valve trains, are therefore challenged by flexible valve trains. The added complexity and additional empirical data needed for wide valve timing ranges limit the usefulness of these methods. A physically-based volumetric efficiency model was developed to address these challenges. The model captures the major physical processes occurring over the intake stroke, and is applicable to both conventional and flexible valve trains. The model inputs include temperature and pressure in the intake and exhaust manifolds, intake and exhaust valve timings, bore, stoke, connecting rod length, engine speed and effective compression ratio, ECR. The model is physically-based, requires no regression tuning parameters, is generalizable to other engine platforms, and has been experimentally validated using an advanced multi-cylinder diesel engine equipped with a flexible variable intake valve actuation system. Experimental data was collected over a wide range of the operating space of the engine and augmented with air handling actuator and intake valve timing sweeps to maximize the range of conditions used to thoroughly experimentally validate the model for a total of 217 total operating conditions. The physical model developed differs from previous physical modeling work through the novel application of ECR, incorporation of no tuning parameters and extensive validation on unique engine test bed with flexible intake valve actuation.

A novel volumetric efficiency model for spark ignition engines equipped with variable valve timing and variable valve lift Part 1: model development

2016 ◽  
Vol 231 (2) ◽  
pp. 175-191 ◽  
Author(s):  
Amir Hasan Kakaee ◽  
Behrooz Mashadi ◽  
Mostafa Ghajar
Keyword(s):  
Experimental Data ◽  
Spark Ignition ◽  
Volumetric Efficiency ◽  
Valve Lift ◽  
Variable Valve Timing ◽  
Spark Ignition Engines ◽  
Valve Timing ◽  
Real Time Applications ◽  
Variable Valve Lift ◽  
Variable Valve

Estimation of the air charge and the volumetric efficiency is one of the most challenging tasks in the control of internal-combustion engines owing to the intrinsic complexity and the non-linearity of the gas flow phenomena. In particular, with emerging new technologies such as systems with variable valve timing and variable valve lift, the number of effective parameters increases greatly, making the estimation task more complicated. On the other hand, using a three-way catalyst converter needs strict control of the air-to-fuel ratio to around the stoichiometric ratio, and hence more accurate models are required for estimation of the air charge. Therefore, various models have been proposed in the literature for estimation of the volumetric efficiency and the air charge. However, they are either strictly based on physical first principles, making them impractical for conventional applications, or nearly fully empirical and need many experimental data for calibration. In this paper, using a novel approach, a new semiempirical model is proposed for estimation of the volumetric efficiency, which is calibrated with very few experimental data and can be used easily for real-time applications. In addition to the valve timings, the engine speed and the intake manifold pressure, the inlet valve lift is also considered as the model input. The generalizability of the model is proved by applying it to estimate the volumetric efficiency of six different engines. Furthermore, a systematic approach is taken to simplify the proposed model and to strengthen its prediction capability. The result is a simple, practical and generalizable model which can be used for various spark ignition engines, can be trained with very few data and can be utilized for estimating accurately the volumetric efficiency in real-time applications.

Investigation and Modification of KIA Pride Engine Intake Valve Timing

2009 ◽  
Author(s):  
Mehdi Sadeghkazemi ◽  
Amir Torabi ◽  
Javad Neyestani
Keyword(s):  
Experimental Data ◽  
Combustion Chamber ◽  
Mesh Generation ◽  
Volumetric Efficiency ◽  
Generation Process ◽  
Intake Valve ◽  
Valve Timing ◽  
Inlet Valve ◽  
Simulation Process ◽  
Exhaust Valves

In this paper, the situation of KIA pride engine intake valve timing has been investigated. To achieve this goal, the geometry of combustion chamber with intake and exhaust valves and runners has been modeled in CATIA. The developed geometry has been transferred to ICEM_CFD package for mesh generation process. In this package, the appropriate grid has been generated for KIVA-3V code, considering all the limitation (1, 2). The simulation process has been accomplished for different engine speeds and validated using available experimental data. Considering the amount of air in combustion chamber right after inlet valve closes, the best valve timing to have maximum volumetric efficiency has been determined. By applying this modification to intake valve timing, the volumetric efficiency increased about 15 percent at low engine speeds. The results of this research can be used for VVT design for the engine.

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