Design, Development, and Evaluation of a Control Framework for an Atkinson Cycle Engine

2017 ◽  
Vol 140 (5) ◽  
Author(s):  
G. Murtaza ◽  
A. I. Bhatti ◽  
Q. Ahmed
Keyword(s):  
Fuel Economy ◽  
Gasoline Engine ◽  
Thermodynamic Cycle ◽  
Mean Value ◽  
Operating Conditions ◽  
Intake Valve ◽  
Design Development ◽  
Engine Model ◽  
Atkinson Cycle ◽  
Control Framework

The efficiency of the spark ignition (SI) engine degrades while working at part loads. It can be optimally dealt with a slightly different thermodynamic cycle termed as an Atkinson cycle. It can be implemented in the conventional SI engines by incorporating advanced mechanisms as variable valve timing (VVT) and variable compression ratio (VCR). In this research, a control framework for the Atkinson cycle engine with flexible intake valve load control strategy is designed and developed. The control framework based on the extended mean value engine model (EMVEM) of the Atkinson cycle engine is evaluated in the view of fuel economy at the medium and higher load operating conditions for the standard new European driving cycle (NEDC), federal urban driving schedule (FUDS), and federal highway driving schedule (FHDS) cycles. In this context, the authors have already proposed a control-oriented EMVEM model of the Atkinson cycle engine with variable intake valve actuation. To demonstrate the potential benefits of the VCR Atkinson cycle VVT engine, for the various driving cycles, in the presence of auxiliary loads and uncertain road loads, its EMVEM model is simulated by using a controller having similar specifications as that of the conventional gasoline engine. The simulation results point toward the significant reduction in engine part load losses and improvement in the thermal efficiency. Consequently, considerable enhancement in the fuel economy of the VCR Atkinson cycle VVT engine is achieved over conventional Otto cycle engine during the NEDC, FUDS, and FHDS cycles.

Effects of intake valve opening duration on performance optimization of an Atkinson cycle engine under part load

2021 ◽  
pp. 095440702110105
Author(s):  
Qingyu Niu ◽  
Baigang Sun ◽  
Yue Wu ◽  
Lingzhi Bao ◽  
Qinghe Luo
Keyword(s):  
Fuel Economy ◽  
Performance Optimization ◽  
Operating Conditions ◽  
Intake Valve ◽  
Compression Pressure ◽  
Part Load ◽  
Atkinson Cycle ◽  
Lower Load ◽  
Valve Opening ◽  
Dimensional Simulation

A comprehensive analysis of the intake valve opening duration (IVOD) effects on the performance of an Atkinson cycle engine is conducted in this work using numerical simulation and experimental validation. Through one-dimensional simulation, the relationship between the range of IVOD and the compression ratios is firstly investigated under the constraint of compression pressure. Two representative IVOD, 295 and 314°CA, are then respectively applied to the performance simulation and experiment of a practical Atkinson cycle engine. The simulation shows the combination of a late intake valve opening timing (IVO) angle and a late exhaust valve opening timing (EVO) angle is profitable for improving the fuel economy under part load operating conditions (i.e. 2000 rpm@2 bar and 3000 rpm@3 bar). The experimental results present the Atkinson cycle engine under both IVOD scenarios considerably improves the brake specific fuel consumption (BSFC) and reduces the pumping mean effective pressure (PMEP) compared to those of the original Otto cycle engine. Meanwhile, the comparison between two IVOD scenarios show that the shorter IVOD leads to an improvement of indicated thermal efficiency, especially at lower load. Considering fuel economy, a shorter IVOD is more favorable at part load for the Atkinson cycle engine. Two main contributions of this work are to numerically quantify the IVOD range for the Atkinson cycle engine under part load, and to experimentally validate the effectiveness of simulation. The findings of this work are expected to support the design of Atkinson cycle engines and provide a guideline of IVOD optimization under part load.

Control-Oriented Model of Atkinson Cycle Engine With Variable Intake Valve Actuation

2016 ◽  
Vol 138 (6) ◽  
Author(s):  
G. Murtaza ◽  
A. I. Bhatti ◽  
Q. Ahmed
Keyword(s):  
Engine Performance ◽  
Mean Value ◽  
Vital Role ◽  
Intake Valve ◽  
Valve Timing ◽  
Part Load ◽  
Engine Model ◽  
Atkinson Cycle ◽  
Engine Part ◽  
Proposed Model

With the advancement in the innovated technologies, optimum efficiency of spark ignition (SI) engine can be accomplished during the entire engine operating range, particularly at part load. In this research, a novel control-oriented extended mean value engine model (EMVEM) of the Atkinson cycle engine is proposed, wherein the Atkinson cycle, variable valve timing (VVT), overexpansion, and variable compression ratio (VCR) characteristics are incorporated. For this purpose, an intake valve timing (IVT) parameter is introduced, which has a vital role in modeling the inclusive dynamics of the system and to deal with engine performance degrading aspects. The proposed model is validated with the experimental data of a VVT engine, obtained from literature, to ensure that the proposed model has the capability to capture the dynamics of the Atkinson cycle engine, and engine load can be controlled by IVT parameter, instead of the conventional throttle. The potential benefits of late intake valve closing (LIVC) tactic and copious integrated characteristics are appreciated as well. Furthermore, simulation results of the developed model primarily indicate the reduction in the engine part load losses and enhancement in thermal efficiency due to overexpansion, which has a great significance in the enhancement of the performance, fuel economy, and emissions reduction. Besides, the constraints on LIVC and overexpansion become evident.

PID-LIKE FLC FOR FOUR CYLINDERS MEAN VALUE GASOLINE ENGINE MODEL IN IDLE MODE

2018 ◽  
Vol 09 (02) ◽  
pp. 114-130
Author(s):  
Mohammed Hassan ◽  
◽  
Muslim Abdali ◽  
Keyword(s):  
Gasoline Engine ◽  
Mean Value ◽  
Idle Mode ◽  
Engine Model ◽  
Four Cylinders

THE STUDY OF THE EFFECT OF INTAKE VALVE TIMING ON ENGINE USING CYLINDER DEACTIVATION TECHNIQUE VIA SIMULATION

2015 ◽  
Vol 77 (8) ◽  
Author(s):  
S. F. Zainal Abidin ◽  
M. F. Muhamad Said ◽  
Z. Abdul Latiff ◽  
I. Zahari ◽  
M. Said
Keyword(s):  
Fuel Consumption ◽  
Internal Combustion Engines ◽  
Gasoline Engine ◽  
Engine Performance ◽  
Intake Valve ◽  
Cylinder Deactivation ◽  
Part Load ◽  
Engine Model ◽  
Engine Efficiency ◽  
Load Conditions

There are many technologies that being developed to increase the efficiency of internal combustion engines as well as reducing their fuel consumption.  In this paper, the main area of focus is on cylinder deactivation (CDA) technology. CDA is mostly being applied on multi cylinders engines. CDA has the advantage to improve fuel consumption by reducing pumping losses at part load engine conditions. Here, the application of CDA on 1.6L four cylinders gasoline engine is studied. One-dimensional (1D) engine modeling work is performed to investigate the effect of intake valve strategy on engine performance with CDA. 1D engine model is constructed based on the 1.6L actual engine geometries. The model is simulated at various engine speeds at full load conditions. The simulated results show that the constructed model is well correlated to measured data. This correlated model is then used to investigate the CDA application at part load conditions. Also, the effects on the in-cylinder combustion as well as pumping losses are presented. The study shows that the effect of intake valve strategy is very significant on engine performance. Pumping losses is found to be reduced, thus improve fuel consumption and engine efficiency.

First Principle-Based Control Oriented Model of a Gasoline Engine

2017 ◽  
Vol 139 (5) ◽  
Author(s):  
Ahmed Yar ◽  
A. I. Bhatti ◽  
Qadeer Ahmed
Keyword(s):  
Mathematical Model ◽  
Gasoline Engine ◽  
Mean Value ◽  
First Principle ◽  
Unified Framework ◽  
Engine Model ◽  
Proposed Model ◽  
Suitable Form ◽  
Speed Fluctuations ◽  
The Mathematical Model

A first principle based-control oriented gasoline engine model is proposed that is based on the mathematical model of the actual piston and crankshaft mechanism. Unlike conventional mean value engine models (MVEMs), which involve approximating the torque production mechanism with a volumetric pump, the proposed model obviates this rather over-simplistic assumption. The alleviation of this assumption leads to the additional features in the model such as crankshaft speed fluctuations and tension in bodies forming the mechanism. The torque production dynamics are derived through Lagrangian mechanics. The derived equations are reduced to a suitable form that can be easily used in the control-oriented model. As a result, the abstraction level is greatly reduced between the engine system and the mathematical model. The proposed model is validated successfully against a commercially available 1.3 L gasoline engine. Being a transparent and more capable model, the proposed model can offer better insight into the engine dynamics, improved control design and diagnosis solutions, and that too, in a unified framework.

scholarly journals TO THE COMPARATIVE EVALUATION OF FUEL ECONOMY OF THE BTR-70 CAR WITH DIFFERENT TRANSMISSION

2021 ◽  
Vol 1 (50) ◽  
pp. 198-209
Author(s):  
Sakhno V ◽  
◽  
Dykich O ◽  
Keyword(s):  
Fuel Consumption ◽  
Fuel Economy ◽  
Comparative Evaluation ◽  
Gasoline Engine ◽  
Fuel Efficiency ◽  
Steady Motion ◽  
Gear Ratio ◽  
Operating Conditions ◽  
Engine Fuel ◽  
Gasoline Engines

The article considers the issue of choosing a gearbox for the modernization of the BTR-70 by replacing two gasoline engines with two diesels. The object of research is the fuel economy of the BTR-70 car with different gearboxes when replacing two gasoline engines with two diesels. The purpose of the work – to determine the type and gear ratio of the transmission, which provides the best fuel efficiency of the car. Research method - mathematical modeling. When replacing a gasoline engine with a diesel of a different power and a different speed range, it is necessary to determine the gear ratio so as to provide the car with the required level of speed properties in the specified operating conditions with minimal fuel consumption. Due to the fact that the modernization of the BTR-70 involves the replacement of the engine and transmission, the further search for the gearbox was carried out on the basis of analysis of existing structures by the maximum torque of the engine. A five-speed and eight-speed MAZ gearbox and a six-speed Mercedes-Benz G 85-6 / 6.7 gearbox were used for analysis. Taking into account the fact that at a given coefficient of drag  = 0.03 the car can move only in direct gear, then for all gearboxes the fuel characteristics of steady motion will be the same as the control fuel consumption, which was 30 l / 100 km. In terms of fuel consumption during the acceleration of the car and the average kilometer fuel consumption when driving on paved roads, preference should be given to a car with a Mercedes-Benz G 85-6 / 6,7 transmission and only when driving in difficult road conditions, preference should be given to the car with 8-speed MAZ-5335 transmission. KEY WORDS: CAR, ENGINE, FUEL ECONOMY, TRANSMISSION, GEAR RATING, SPEED, COMPARATIVE EVALUATION

scholarly journals Study on Valve Strategy of Variable Cylinder Deactivation Based on Electromagnetic Intake Valve Train

2018 ◽  
Vol 8 (11) ◽  
pp. 2096 ◽  
Author(s):  
Maoyang Hu ◽  
Siqin Chang ◽  
Yaxuan Xu ◽  
Liang Liu
Keyword(s):  
Gasoline Engine ◽  
Transition Period ◽  
Valve Train ◽  
Exhaust Pipe ◽  
Intake Valve ◽  
Cylinder Deactivation ◽  
Engine Model ◽  
Brake Mean Effective Pressure ◽  
Variable Valve Train ◽  
Variable Valve

The camless electromagnetic valve train (EMVT), as a fully flexible variable valve train, has enormous potential for improving engine performances. In this paper, a new valve strategy based on the electromagnetic intake valve train (EMIV) is proposed to achieve variable cylinder deactivation (VCD) on a four-cylinder gasoline engine. The 1D engine model was constructed in GT-Power according to test data. In order to analyze the VCD operation with the proposed valve strategy, the 1D model was validated using a 3D code. The effects of the proposed valve strategy were investigated from the perspective of energy loss of the transition period, the mass fraction of oxygen in the exhaust pipe, and the minimum in-cylinder pressure of the active cycle. On the premise of avoiding high exhaust oxygen and oil suction, the intake valve timing can be determined with the variation features of energy losses. It was found that at 1200 and 1600 rpm, fuel economy was improved by 12.5–16.6% and 9.7–14.6%, respectively, under VCD in conjunction with the early intake valve closing (EIVC) strategy when the brake mean effective pressure (BMEP) ranged from 0.3 MPa to 0.2 MPa.

Thermodynamics-Based Mean Value Model for Diesel Combustion

2013 ◽  
Vol 135 (9) ◽  
Author(s):  
Byungchan Lee ◽  
Dohoy Jung ◽  
Yong-Wha Kim ◽  
Michiel van Nieuwstadt
Keyword(s):  
Combustion Process ◽  
Mean Value ◽  
Ideal Gas ◽  
Operating Conditions ◽  
Strategy Development ◽  
Diesel Combustion ◽  
Engine Model ◽  
Exhaust Temperature ◽  
Mean Value Model ◽  
Value Model

A thermodynamics-based computationally efficient mean value engine model that computes ignition delay, combustion phases, exhaust temperature, and indicated mean effective pressure has been developed for the use of control strategy development. The model is derived from the thermodynamic principles of ideal gas standard limited pressure cycle. In order to improve the fidelity of the model, assumptions that are typically used to idealize the cycle are modified or replaced with ones that more realistically replicate the physical process such as exhaust valve timing, in-cylinder heat transfer, and the combustion characteristics that change under varying engine operating conditions. The model is calibrated and validated with the test data from a Ford 6.7 liter diesel engine. The mean value model developed in this study is a flexible simulation tool that provides excellent computational efficiency without sacrificing critical details of the underlying physics of the diesel combustion process.

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