Applications of VVT and VCR on Fuel Economy Improvement Based Engine Electronic Control

2004 ◽  
Author(s):  
Zhengmao Ye ◽  
Ming-Chia Lai
Keyword(s):  
Fuel Economy ◽  
Gasoline Engine ◽  
Fuel Injection ◽  
Engine Performance ◽  
Performance And Emission ◽  
Fuel Economy Improvement ◽  
Operating Regions ◽  
Economy Benefit ◽  
Variable Valve ◽  
Maximal Benefit

Variable valve timing (VVT) and variable compression ratio (VCR) are two technologies to obtain fuel economy benefit. On the other hand, there is a tradeoff among fuel economy, engine performance and emission levels. Advantages of two technologies vary a lot on different engine operating regions. Recently some experiments are conducted on a Port Fuel Injection (PFI) engine in a city drive cycle to investigate the fuel economy impact from VVT, VCR and the technology integration. The testing results show clearly that the synergy of two technologies has further improved the fuel economy, while suitable operating regions need to be determined where the maximal benefit can be achieved. A typical 1.8L four-cylinder gasoline engine is used for experiments using VVT and VCR technologies for fuel economy improvement. The objective is to create a synergy scheme for the optimal fuel economy performance. The supercharged testing engine with VVT and VCR can implement similar performance to that of a larger replacement engine. The fuel economy optimization problem is simply converted into searching for the lowest engine power output region with respect to the same fuel economy improvement level. These optimal points are useful to determine potential best fuel economy operating regions whether VVT and VCR should be implemented individually or combined together.

Fuel Economy Improvement Potential of a PFI Gasoline Engine Using VVT/VCR

2004 ◽  
Author(s):  
Frank M. Washko ◽  
Ming-Chia Lai
Keyword(s):  
Fuel Economy ◽  
Gasoline Engine ◽  
Fuel Efficiency ◽  
Operating Efficiency ◽  
Powertrain System ◽  
Improvement Potential ◽  
Fuel Economy Improvement ◽  
The Many ◽  
System Variables ◽  
Variable Valve

It is desired to optimize a spark ignition PFI (port fuel injected) engine for various regimes within the operating ranges of a vehicle. The goal of this work is to identify the set of technologies that complement each other and offer the optimum performance and fuel economy. For an ideal powertrain system, the engine should be optimized for best fuel economy during the typical drive cycles and best performance during high load acceleration. A typical PFI 1.8L four-cylinder engine is baselined at cycle representative speed/load points. The engine is supercharged and intercooled to later quantify the efficiency benefits from replacing a larger engine with a smaller boosted engine that offers similar performance. Then the effects of different operating regimes and the effect of different proposed technologies are studied. The fuel economy enablers considered include variable valve timing (VVT) and variable compression ratios (VCR). The effects of VVT was studied to see which valve event scenarios afford the best operating efficiency and fuel economy during part load operation. VVT can also be a source of performance improvement if implemented appropriately. VCR operation is studied to see if the efficiency gains from VCR are additive with VVT or if they overlap to some degree. Typically, the fuel efficiency potential of a production engine is limited by spark knock. The engine studied here uses the geometrical and virtual compression ratio reductions offered by the VVT and VCR systems to give knock limit relief and allows the knock-limited BMEP curve to be pushed up. The results showed that the fuel economy gain with the above mentioned technologies is somewhat additive throughout the typical driving cycle but is highly dependent on proper optimization of the many system variables.

scholarly journals Effect of Methanol/Water Mixed Fuel Compound Injection on Engine Combustion and Emissions

Energies ◽  
2021 ◽  
Vol 14 (15) ◽  
pp. 4491
Author(s):  
Changchun Xu ◽  
Haengmuk Cho
Keyword(s):  
Fuel Consumption ◽  
Ignition Delay ◽  
Fuel Injection ◽  
Fuel Efficiency ◽  
Engine Performance ◽  
Hydroxyl Group ◽  
Combustion Mechanism ◽  
Performance And Emission ◽  
Reduce Emissions ◽  
Concentration Ratios

Due to the recent global increase in fuel prices, to reduce emissions from ground transportation and improve urban air quality, it is necessary to improve fuel efficiency and reduce emissions. Water, methanol, and a mixture of the two were added at the pre-intercooler position to keep the same charge and cooling of the original rich mixture, reduce BSFC and increase ITE, and promote combustion. The methanol/water mixing volume ratios of different fuel injection strategies were compared to find the best balance between fuel consumption, performance, and emission trends. By simulating the combustion mechanism of methanol, water, and diesel mixed through the Chemkin system, the ignition delay, temperature change, and the generation rate of the hydroxyl group (−OH) in the reaction process were analyzed. Furthermore, the performance and emission of the engine were analyzed in combination with the actual experiment process. This paper studied the application of different concentration ratios of the water–methanol–diesel mixture in engines. Five concentration ratios of water–methanol blending were injected into the engine at different injection ratios at the pre-intercooler position, such as 100% methanol, 90% methanol/10% water, 60% methanol/40% water, 30% methanol/70% water, 100% water was used. With different volume ratios of premixes, the combustion rate and combustion efficiency were affected by droplet extinguishment, flashing, or explosion, resulting in changes in combustion temperature and affecting engine performance and emissions. In this article, the injection carryout at the pre-intercooler position of the intake port indicated thermal efficiency increase and a brake specific fuel consumption rate decrease with the increase of water–methanol concentration, and reduce CO, UHC, and nitrogen oxide emissions. In particular, when 60% methanol and 40% water were added, it was found that the ignition delay was the shortest and the cylinder pressure was the largest, but the heat release rate was indeed the lowest.

Economy and emission characteristics of the optimal dilution strategy in lean combustion based on GDI gasoline engine equipped with prechamber

2021 ◽  
Vol 13 (12) ◽  
pp. 168781402110381
Author(s):  
Li Wang ◽  
Zhaoming Huang ◽  
Wang Tao ◽  
Kai Shen ◽  
Weiguo Chen
Keyword(s):  
Fuel Economy ◽  
Gasoline Engine ◽  
Direct Injection ◽  
Engine Performance ◽  
Gasoline Direct Injection ◽  
Dilution Ratio ◽  
Lean Combustion ◽  
Excess Air ◽  
Combustion Phase ◽  
Hc Emissions

EGR and excess-air dilution have been investigated in a 1.5 L four cylinders gasoline direct injection (GDI) turbocharged engine equipped with prechamber. The influences of the two different dilution technologies on the engine performance are explored. The results show that at 2400 rpm and 12 bar, EGR dilution can adopt more aggressive ignition advanced angle to achieve optimal combustion phasing. However, excess-air dilution has greater fuel economy than that of EGR dilution owing to larger in-cylinder polytropic exponent. As for prechamber, when dilution ratio is greater than 37.1%, the combustion phase is advanced, resulting in fuel economy improving. Meanwhile, only when the dilution ratio is under 36.2%, the HC emissions of excess-air dilution are lower than the original engine. With the increase of dilution ratio, the CO emissions decrease continuously. The NOX emissions of both dilution technologies are 11% of those of the original engine. Excess-air dilution has better fuel economy and very low CO emissions. EGR dilution can effectively reduce NOX emissions, but increase HC emissions. Compared with spark plug ignition, the pre chamber ignition has lower HC, CO emissions, and higher NO emissions. At part load, the pre-chamber ignition reduces NOX emissions to 49 ppm.

scholarly journals Review of Performance and Emmissions Characteristics of Bio-Additive Fuel on SI Engine Fuelled by Biopetrol

2015 ◽  
Vol 773-774 ◽  
pp. 430-434
Author(s):  
Azizul Mokhtar ◽  
Nazrul Atan ◽  
Najib Rahman ◽  
Amir Khalid
Keyword(s):  
Fuel Economy ◽  
Fossil Fuels ◽  
Review Paper ◽  
Engine Performance ◽  
Exhaust Emissions ◽  
Spark Ignition Engine ◽  
Si Engine ◽  
New Approach ◽  
Performance And Emission ◽  
Performance And Emissions

Bio-additive is biodegradable and produces less air pollution thus significant for replacing the limited fossil fuels and reducing threats to the environment from exhaust emissions and global warming. Instead, the bio-additives can remarkably improve the fuel economy SI engine while operating on all kinds of fuel. Some of the bio-additive has the ability to reduce the total CO2 emission from internal petrol engine. This review paper focuses to determine a new approach in potential of bio-additives blends operating with bio-petrol on performance and emissions of spark ignition engine. It is shown that the variant in bio-additives blending ratio and engine operational condition are reduced engine-out emissions and increased efficiency. It seems that the bio-additives can increase the maximum cylinder combustion pressure, improve exhaust emissions and largely reduce the friction coefficient. The review concludes that the additives usage in bio-petrol is inseparable for the better engine performance and emission control and further research is needed to develop bio-petrol specific additives.

scholarly journals Performance Assessment of DI-Diesel Engine using the Blend of Sunflower Oil and Rice Bran Oil

2019 ◽  
Vol 8 (4) ◽  
pp. 4048-4052
Keyword(s):  
Diesel Engine ◽  
Sunflower Oil ◽  
Fuel Injection ◽  
Rice Bran Oil ◽  
Engine Performance ◽  
Performance And Emission ◽  
Animal Fats ◽  
Di Diesel Engine ◽  
Hc Emissions ◽  
Direct Fuel Injection

Biodiesel, a derivative of vegetable oils and animal fats, is used nowadays as an alternative renewable and sustainable fossil fuel. In this work, the investigation of manufacture, characterization, and results of biodiesel blends are carried out using two important feedstock’s, sunflower oil and ricebran oil on engines. For the collective advantageous of sunflower oil and ricebran oil, the two biodiesels are combined together and the mixture is analysed to assess the engine performance and emission characteristics. NaOH catalyzed transesterification process is used for producing the Biodiesels A 4.4 kW, four-stroke, single-cylinder and direct fuel injection diesel engine is used for measuring physic-chemical with full load and varying speed conditions and using the specifications of ASTM D6751 standard, the properties are compared. It is observed that the Biodiesel mixtures produce a low brake torque and high brake-specific fuel consumption (BSFC) in addition to the reduction of CO and HC emissions. NOx, however, is reduced considerably with the improvement of brake thermal efficiency. The Performance analysis indicates that the mixture of sunflower oil and ricebran oil improves performance and emission characterizes over sunflower oil and ricebran oil biodiesel when they are unmixed..

Automated Engine Calibration Optimization Using Online Extremum Seeking

2018 ◽  
Author(s):  
Ripudaman Singh ◽  
Andrew Mansfield ◽  
Margaret Wooldridge
Keyword(s):  
Control Parameter ◽  
Gasoline Engine ◽  
Fuel Injection ◽  
Engine Performance ◽  
Extremum Seeking ◽  
Injection System ◽  
Test Time ◽  
Injection Timing ◽  
Promising Alternative ◽  
Non Linear System

Emissions compliance during engine start-up conditions is a major obstacle for current automotive manufacturers across global markets. The challenges to meeting emissions targets are both due to increasingly stringent regulations and the difficulty in developing control strategies for a high degree-of-freedom and highly non-linear system. Online extremum-seeking (ES) methods offer a promising alternative to traditional optimization based on design-of-experiment based automotive calibration. With extremum-seeking methods, results from all prior experiments are used to intelligently and efficiently generate the next iteration of the control parameter(s). In this work, the applicability of the online extremum-seeking method is explored to optimize five performance variables (injection timing for two injection events, the injection fuel mass divided between the first and second injection events, air-fuel equivalence ratio and exhaust cam timing) to minimize brake specific fuel consumption while imposing different constraints on NOx emissions. The experiments were conducted using a production turbocharged four-cylinder gasoline engine with an advanced fuel injection system. The results show the utility of the ES strategy to quickly identify optimal control parameter combinations and the emissions and engine performance improvements during the calibration process. The results also demonstrate the dramatic benefit of the ES calibration strategy in terms of test time required.

Development Concept for Non Conventional Hybrid Engine

2010 ◽  
Author(s):  
Harsh Purohit ◽  
Ankit Shah ◽  
Nishant Parekh ◽  
Akash Pandey
Keyword(s):  
Fuel Economy ◽  
Internal Combustion Engines ◽  
Gasoline Engine ◽  
Direct Injection ◽  
Combustion Engines ◽  
Common People ◽  
Advantages And Disadvantages ◽  
Compact Size ◽  
Hybrid Engines ◽  
Variable Valve

Environmental issues and the need for environment-friendly transport have always been a priority for the world due to ever increasing demand of modes of transport. So developing quick and eco friendly vehicle is the trend as of now with most manufacturers globally. There are numerous ways in which manufacturers have tackled these issues. Some of the common approaches undertaken are refinements of existing internal combustion engines. Like developing technologies such as direct injection, VVT (variable valve time), VTEC (variable valve time electronic lift), VGT (variable geometry turbines), reducing engine friction and weight, cam less engines, micro hybrids, etc But the best/optimum compromise between eco friendliness and urge to develop more power with good fuel economy and reduced emission is best met by the development of hybrid engines. Thermal and electric engines both have advantages and disadvantages that are often complementary. Combustion engines offer better range, power and ‘lunge’, but give out exhaust gas, although the current Euro IV norm place strict limits on these. Electric engines are zero-emission and offer very quick pick-up from a stopped position, but the batteries have low range and limited speed. So this complementation of both power trains is exploited in hybrid engines. Now conventional hybrids have many disadvantages such as being bulky with additional weight of battery packs and motors and other auxiliary transmission components, complex and dangerous electric systems, etc. So it is proposed to develop a non conventional hybrid engine which produces power at par with the conventional one and releases emission which is compatible with the stringent emission norms set for the conventional hybrids with considerably lucrative fuel economy comparable with the currently available hybrids in market and yet overcome the drawbacks of the conventional hybrid engines. Also the compact size of the hybrid engine that we propose makes it quite viable to fitted in small vehicles (like bikes, compact cars, etc) which further makes it a more promising technology that can be made available to common people across the globe and there by lead to a better transportation system for people of all class and need. The conceptualization basically includes modification of an inline twin cylinder or a v-twin 4-stroke gasoline engine as a preliminary step towards achieving the above proposed objectives.

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