Novel Engine Cycle Enabling Partial Load Fuel Efficiency Beyond Full Load Conditions

Author(s):  
Arjen de Jong

Abstract Fuel consumption reduction and emission reductions in internal combustion engines (ICE) is a hot topic nowadays. An adaption of cylinder de-activation technique called ECONAMIQ over-expansion can be applied to engines to improve fuel efficiency. Using the pressure from the exhaust gas from the active cylinders, the ‘idle’ cylinders could be expanded to extract more work out of the engine during partial load operation. Using the virtual simulation environment GT-Power, this cycle is applied to a 4-cylinder SI engine. This engine model is simulated for a part load operation point and compared with a standard 4-cylinder engine model and 4-cylinder engine model equipped with cylinder de-activation. From these simulations various variables for engine operation (valve timing etc.) are optimized to further reduce fuel consumption of the engine. A final brake specific fuel consumption reduction of over 10% is achieved using the overexpansion cycle, while improving engine performance on two burning cylinders over 10% as well. With this improvement it is shown that the over-expansion cycle has a significant benefit compared to a standard ICE and cylinder de-activation techniques. These simulations are being validated on an engine test dyno using a natural aspirated ICE.

2015 ◽  
Vol 77 (8) ◽  
Author(s):  
S. F. Zainal Abidin ◽  
M. F. Muhamad Said ◽  
Z. Abdul Latiff ◽  
I. Zahari ◽  
M. Said

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.


2021 ◽  
Vol 13 (13) ◽  
pp. 7043
Author(s):  
Fangzi Liu ◽  
Zihong Li ◽  
Hua Xie ◽  
Lei Yang ◽  
Minghua Hu

Investigating potential ways to improve fuel efficiency of aircraft operations is crucial for the development of the global air traffic management (ATM) performance target. The implementation of trajectory-based operations (TBOs) will play a major role in enhancing the predictability of air traffic and flight efficiency. TBO also provides new means for aircraft to save energy and reduce emissions. By comprehensively considering aircraft dynamics, available route limitations, sector capacity constraints, and air traffic control restrictions on altitude and speed, a “runway-to-runway” four-dimensional trajectory multi-objective planning method under loose-to-tight heterogeneous constraints is proposed in this paper. Taking the Shanghai–Beijing city pair as an example, the upper bounds of the Pareto front describing potential fuel consumption reduction under the influence of flight time were determined under different airspace rigidities, such as different ideal and realistic operating environments, as well as fixed and optional routes. In the congestion-free scenario with fixed route, the upper bounds on fuel consumption reduction range from 3.36% to 13.38% under different benchmarks. In the capacity-constrained scenario, the trade-off solutions of trajectory optimization are compressed due to limited available entry time slots of congested sectors. The results show that more flexible route options improve fuel-saving potentials up to 8.99%. In addition, the sensitivity analysis further illustrated the pattern of how optimal solutions evolved with congested locations and severity. The outcome of this paper would provide a preliminary framework for predicting and evaluating fuel efficiency improvement potentials in TBOs, which is meaningful for setting performance targets of green ATM systems.


Author(s):  
Christopher J. Simoson ◽  
John R. Wagner

Diesel engines fulfill diverse demands in urban and rural areas throughout the world. While the advantages of compression ignition engines are superior to other internal combustion engines in torque generation and fuel efficiency, some diesel exhaust emissions pose health and environmental problems. Emission reduction techniques generally diminish one type of tailpipe gas yet often sacrifice engine performance and may even raise other emission levels. For instance, exhaust gas recirculation can reduce NOx emissions. However, the dilution of the combustion charge with hot inert exhaust gas hinders the engine’s power characteristics. To solve this problem, an EGR cooler allows the exhaust gases to be cooled prior to mixing with intake air allowing a denser cylinder charge for combustion. The effective application of cooled EGR requires a smart thermal management system. In this paper, a real time empirical and analytical model will be introduced to estimate the diesel engine’s overall performance. The simplified model considers the engine’s combustion chemistry, as well as the thermal, emissions, and rotational dynamics. Representative numerical and experimental test results are presented and discussed to validate the model. Eventually, an on-board computer controller will use this model to regulate the EGR valve’s functionality and the smart thermal system.


Author(s):  
N.S. Mustafa ◽  
N.H.A. Ngadiman ◽  
M.A. Abas ◽  
M.Y. Noordin

Fuel price crisis has caused people to demand a car that is having a low fuel consumption without compromising the engine performance. Designing a naturally aspirated engine which can enhance engine performance and fuel efficiency requires optimisation processes on air intake system components. Hence, this study intends to carry out the optimisation process on the air intake system and airbox geometry. The parameters that have high influence on the design of an airbox geometry was determined by using AVL Boost software which simulated the automobile engine. The optimisation of the parameters was done by using Design Expert which adopted the Box-Behnken analysis technique. The result that was obtained from the study are optimised diameter of inlet/snorkel, volume of airbox, diameter of throttle body and length of intake runner are 81.07 mm, 1.04 L, 44.63 mm and 425 mm, respectively. By using these parameters values, the maximum engine performance and minimum fuel consumption are 93.3732 Nm and 21.3695×10-4 kg/s, respectively. This study has fully accomplished its aim to determine the significant parameters that influenced the performance of airbox and optimised the parameters so that a high engine performance and fuel efficiency can be produced. The success of this study can contribute to a better design of an airbox.


Author(s):  
Petar Kazakov ◽  
Atanas Iliev ◽  
Emil Marinov

Over the decades, more attention has been paid to emissions from the means of transport and the use of different fuels and combustion fuels for the operation of internal combustion engines than on fuel consumption. This, in turn, enables research into products that are said to reduce fuel consumption. The report summarizes four studies of fuel-related innovation products. The studies covered by this report are conducted with diesel fuel and usually contain diesel fuel and three additives for it. Manufacturers of additives are based on already existing studies showing a 10-30% reduction in fuel consumption. Comparative experimental studies related to the use of commercially available diesel fuel with and without the use of additives have been performed in laboratory conditions. The studies were carried out on a stationary diesel engine СМД-17КН equipped with brake КИ1368В. Repeated results were recorded, but they did not confirm the significant positive effect of additives on specific fuel consumption. In some cases, the factors affecting errors in this type of research on the effectiveness of fuel additives for commercial purposes are considered. The reasons for the positive effects of such use of additives in certain engine operating modes are also clarified.


Energies ◽  
2021 ◽  
Vol 14 (15) ◽  
pp. 4491
Author(s):  
Changchun Xu ◽  
Haengmuk Cho

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.


2021 ◽  
Vol 8 (1) ◽  
pp. H16-H20
Author(s):  
A.V.N.S. Kiran ◽  
B. Ramanjaneyulu ◽  
M. Lokanath M. ◽  
S. Nagendra ◽  
G.E. Balachander

An increase in fuel utilization to internal combustion engines, variation in gasoline price, reduction of the fossil fuels and natural resources, needs less carbon content in fuel to find an alternative fuel. This paper presents a comparative study of various gasoline blends in a single-cylinder two-stroke SI engine. The present experimental investigation with gasoline blends of butanol and propanol and magnesium partially stabilized zirconium (Mg-PSZ) as thermal barrier coating on piston crown of 100 µm. The samples of gasoline blends were blended with petrol in 1:4 ratios: 20 % of butanol and 80 % of gasoline; 20 % of propanol and 80 % of gasoline. In this work, the following engine characteristics of brake thermal efficiency (BTH), specific fuel consumption (SFC), HC, and CO emissions were measured for both coated and non-coated pistons. Experiments have shown that the thermal efficiency is increased by 2.2 % at P20. The specific fuel consumption is minimized by 2.2 % at P20. Exhaust emissions are minimized by 2.0 % of HC and 2.4 % of CO at B20. The results strongly indicate that the combination of thermal barrier coatings and gasoline blends can improve engine performance and reduce exhaust emissions.


Author(s):  

The prospects of using hydrogen as a motor fuel are noted. The problems that arise when converting a diesel engine to run on hydrogen are considered. The features of the organization of the working process of enginesrunning on hydrogen are analyzed. A method of supplying a hydrogenair mixture to a diesel engine is investigated. To supply hydrogen to the engine cylinders, it is proposed to use the Leader4M installation developed by TechnoHill Club LLC (Moscow). Experimental studies of a stationary diesel engine of the D245.12 S type with the supply of hydrogen at the inlet obtained at this installation are carried out. At the maximum power mode, the supply of hydrogen from this installation to the inlet of the diesel engine under study was 0.9 % by weight (taking into account the difference in the calorific value of oil diesel fuel and hydrogen). Such a supply of hydrogen in the specified mode made it possible to increase the fuel efficiency of the diesel engine and reduce the smoke content of exhaust gases, carbon monoxide and unburned hydrocarbon emissions. Keywords internal combustion engines; diesel engine; diesel fuel; hydrogen; hydrogenair mixture; fuel efficiency; exhaust gas toxicity indicators


Author(s):  
Gianluca Pasini ◽  
Stefano Frigo ◽  
Marco Antonelli

At present, the application of turbocharging in compression ignition (CI) engines represents almost all of the applications, especially for transportation where fuel efficiency and low emissions are the main targets. Following this approach, the possibility to couple an electric drive to the turbocharger (electric turbo compound, ETC) to recover the residual energy of the exhaust gases is becoming more and more attractive, as demonstrated by several studies around the world. The present paper shows the first numerical results of a research program under way which is focused on the comparison of the benefits resulting from the application of two ETC configurations to a four cylinders CI engine (1561 cm3). In the first configuration, called single-ETC, a variable geometry turbocharger (VGT) is coupled to an electric generator (mechanic connection); in the second, called dual ETC, the two turbomachines (the variable nozzle turbine and the compressor) are separated and each one is coupled to its own electric machine. Starting from the experimental maps of the turbine and compressor, the complete engine model was created using the AVL BOOST one-dimension code. Compared with the no-ETC engine, the adoption of the single-ETC shows interesting benefits in term of energy recovery at the highest engine speeds and loads, with consequent decrease of fuel consumption. Dual ETC allows the operation of turbine and compressor at different speeds with further reduction of the total brake specific fuel consumption.


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