scholarly journals The efficiency engine – cost-effective alternative to downsizing

2012 ◽  
Vol 149 (2) ◽  
pp. 3-9
Author(s):  
Michael WEISSBÄCK ◽  
Mike HOWLETT ◽  
Norbert AUSSERHOFER ◽  
Stefan KRAPF

As an alternative to the familiar option of downsizing diesel engines, AVL has developed the so-called efficiency engine in collaboration with Renault. Because of the engine’s moderate power density, its peak pressure requirements are lower in some areas than those of turbocharged gasoline engines. Consequently, its mechanical friction and fuel consumption can be significantly reduced, as the comparison with a conventional and a downsized diesel engine demonstrates.

Author(s):  
Kuo Yang ◽  
Pingen Chen

Abstract Engine efficiency improvement is very critical for medium to heavy-duty vehicles to reduce Diesel fuel consumption and enhance U.S. energy security. The tradeoff between engine efficiency and NOx emissions is an intrinsic property that prevents modern Diesel engines, which are generally equipped with exhaust gas recirculation (EGR) and variable geometry turbocharger (VGT), from achieving the optimal engine efficiency while meeting the stringent NOx emission standards. The addition of urea-based selective catalytic reduction (SCR) systems to modern Diesel engine aftertreatment systems alleviate the burden of NOx emission control on Diesel engines, which in return creates extra freedom for optimizing Diesel engine efficiency. This paper proposes two model-based approaches to locate the optimal operating point of EGR and VGT in the air-path loop to maximize the indicated efficiency of turbocharged diesel engine. Simulation results demonstrated that the engine brake specific fuel consumption (BSFC) can be reduced by up to 1.6% through optimization of EGR and VGT, compared to a baseline EGR-VGT control which considers both NOx emissions and engine efficiency on engine side. The overall equivalent BSFCs are 1.8% higher with optimized EGR and VGT control than with the baseline control. In addition, the influence of reducing EGR valve opening on the non-minimum phase behavior of the air path loop is also analyzed. Simulation results showed slightly stronger non-minimum phase behaviors when EGR is fully closed.


Author(s):  
A.V. Nelidkin ◽  
◽  
S.N. Borychev ◽  
D.O. Oleynik ◽  
◽  
...  

To ensure high quality and productive work of employ-ees, it is necessary to achieve the target parameters of the microclimate and to exclude harmful and toxic substances in the atmosphere of the working area of agricultural prem-ises of a closed volume and air exchange. The main rea-son for the distortion of the air-gas regime of the room is the use of agricultural machines in closed industrial prem-ises (warehouses, storage facilities, livestock facilities, etc.). As a result, there is a decrease in the quality of prod-ucts and working conditions at agricultural enterprises, as well as a reduction in the operational life of structures. To-day, in agricultural machinery, diesel engines are most often used as power units which, unlike gasoline engines are more economical, and also reduce the harmful impact on the environment. But, despite this, the operation of die-sel engines still causes the accumulation of harmful com-ponents in the atmosphere of the room which negatively affects the health of the staff. The analysis of the designs of devices for exhaust gas purificationof internal combus-tion engines revealed the problems that affect the efficien-cy of the purification. The most significant problems are as following: large weight and dimensions, reduced efficiency of the neutralizers when the engine is running at modes close to the nominal ones, and large gas-dynamic re-sistance. To solve these problems, the design of a device for exhaust gas purificationin diesel engines was devel-oped. The use of this utility model will increase the efficien-cy of the device for exhaust gas purification. It will improve the environmental performance of the diesel engine reduc-ing emissions of harmful substances and soot into the at-mosphere.


ROTASI ◽  
2014 ◽  
Vol 16 (4) ◽  
pp. 48
Author(s):  
Syaiful Syaiful ◽  
Iseu Andriani

Diesel engines many are used as transportation mode in the land and sea compared with gasoline engines due to their high efficiency and durability. However, diesel engine releases much more NOx and soot emissions than that of gasoline engine. NOx is formed from a reaction of Nitrogen and Oxygen at high temperature. If these emissions are breathed into human body resulting respiratory disorders such as emphysema and bronchitis as well as lungs tissue damage. Therefore, NOx emissions controll is required to reduce them reaching under a threshold level. An effective method for controlling NOx emissions produced by the diesel engines is by injecting ammonia obtained from urea into selective catalytic reduction (SCR method) system. Ammonia by means of catalyst reacts with NOx forming Nitrogen (N2) and Water (H2O). Therefore, a chance of each ammonia particle to react with each NOx particle is required to consider. A reaction quality between ammmonia and NOx particles can be increased by improving a mixing index. One of the methods to increase the mixing index is by using a dynamic mixer.There are several factors which influence the increase of mixing index. One of these factors is a location of ammonia injector. Since this work is focused on investigating the effect of ammonia injector location on the mixing index of ammonia to diesel engine exhaust gases which content of NOx emissions


Energies ◽  
2021 ◽  
Vol 14 (12) ◽  
pp. 3472
Author(s):  
Dariusz Kurczyński ◽  
Grzegorz Wcisło ◽  
Piotr Łagowski

The use of biofuel is one method for limiting the harmful impact of diesel engines on the environment. It is also a way of gradually becoming less dependent on the depleting petroleum resources. New resources for producing biodiesel are currently being sought. The authors produced esters from animal fat waste, obtaining a fuel that can power diesel engines and identifying a way to utilise unnecessary waste. The animal fat methyl ester (AME) was produced using a reactor constructed for non-industrial ester production. The aim underlying this paper was to determine whether a diesel engine can be fuelled with AME biodiesel and to test this fuel’s impact on exhaust gas composition and fuel consumption. Fuelling a Perkins 1104D-44TA engine with AME biodiesel led to a reduction in the smoke opacity of the exhaust gas as well as in carbohydrate, particulate matter, and carbon monoxide concentrations. The carbon dioxide concentrations were similar for biodiesel and diesel fuel. Slight increases in nitrogen oxides concentrations and brake-specific fuel consumption were found for AMEs. An engine can be fuelled with AME biodiesel, but it is necessary to improve its low-temperature properties.


2020 ◽  
Vol 6 (2) ◽  
pp. 108-113 ◽  
Author(s):  
Kianoosh Shojae ◽  
Majid Mahdavian

Background: Vegetable oil of Fatty Acid Methyl Esters (FAME) that is obtained by triglycerides of transesterification in the presence of methanol, recently, has been highly regarded by scholars for use in diesel engines. These oils can be used as biodiesels in diesel engines and have various benefits (these fuels are renewable, biodegradable, and nontoxic). Objective: In this work, many studies are reviewed in the field of using vegetable oils as biodiesel in diesel engines. Moreover, a simulation study is conducted to compare oxygen and peak pressure of a diesel engine fueled by three different biodiesels in comparison to diesel fuel. We have examined the chemical ignition delay time and kinetic viscosity of biodiesel in the combustion process of diesel engine and the effects of these factors are evaluated on air–fuel mixing and subsequent combustion.


2015 ◽  
Author(s):  
S. Bari ◽  
Idris Saad

Diesel engine can be run with renewable biodiesel which has the potential to supplement the receding supply of crude oil. Use of biodiesel in diesel engines can also reduce harmful emissions of CO, unburned HC and particulates. As biodiesel possess similar physiochemical properties to diesel, most diesel engines can be run with biodiesel with minimum modifications. However, the viscosity and calorific values of biodiesel are higher and lower, respectively than diesel which will affect the performance of diesel engine run with biodiesel. Use of 100% biodiesel in diesel engines shows inferior performance of having lower power and torque. Guide vanes into the intake runner to improve the in-cylinder airflow characteristic to break down higher viscous biodiesel is the aim of this research. This is expected to improve the air-fuel mixing resulting better combustion. The experimental results of biodiesel run in a diesel-gen set showed that break specific fuel consumption reduced in between 0.90 and 1.77% with vane numbers of 3 to 5. In regards to emissions, CO reduced in the range 0.05 and 8.78%, CO2 reduced in the range of 0.82 and 1.75%, and HC in the range of 1.19 and 7.49% with vane numbers of 3 to 5. Interestingly, most improvements were found with the vane numbers of 4.


Author(s):  
Alexander Fedorovich Dorokhov ◽  
Pavel Aleksandrovitch Dorokhov

The article considers ship swirl-chamber diesel engines used in shipbuilding as the main and auxiliary engines. Two reasons for low profitability of the swirl chamber diesel engines are highlighted: large heat losses of the cooling working fluid due to the extended heat transfer surface of the chamber, and significant aerodynamic energy losses of compressed air during its passage through a relatively narrow channel connecting the piston chamber with the combustion chamber and the flow of gases from the swirl chamber on top the piston space. There have been proposed the methods for improving the operational performance of swirl-chamber diesels in production, in particular, their fuel efficiency. The scheme of the swirl-chamber and a section of the swirl-chamber cylinder head are presented. It has been stated that the total coefficient of thermal conductivity can be reduced if the wall of the swirl- chamber is made multi-layer. The layouts of a multi-layer cylinder-spherical wall of a swirl combustion chamber with a titanium cylinder-spherical insertion and thermal insulation of a vortex combustion chamber are given. The total thermal resistance of the spherical wall was calculated, heat loss through the multilayer spherical wall was determined, gas temperature in the vortex chamber was calculated, according to the average cycle temperature diagram. It was inferred that the amount of heat removed from the working fluid to cooling through the thermally insulated wall of the swirl-chamber will be 40% less than the amount of heat released to the cooling through the wall of the swirl-chamber of a commercial diesel engine. The difference in heat will be used to increase the indicator gas operation, which, with the same cyclic fuel supply, will lead to a decrease in the specific indicator fuel consumption, and at a constant level of internal engine losses - to a decrease in the specific effective fuel consumption.


2007 ◽  
Vol 129 (2) ◽  
pp. 33-37
Author(s):  
Giovanni CIPOLLA

The article describes some predictions with regard to developing trends of automotive propulsion systems. According to the author’s opinion, Diesel engines will share with the gasoline one the leadership of the market in the short-to-middle timeframe, with shares depending mainly from regional contingencies. In the middle-to-long timeframe, the hybrid powertrain and fuel cells will became a real alternative option to conventional engine. However, Diesel hybrid powertrain could also became a very interesting opportunity, because the Diesel engine features will further improve the fuel consumption and the fun-to-drive features of hybrid systems.


Mechanika ◽  
2020 ◽  
Vol 26 (6) ◽  
pp. 486-496
Author(s):  
Ádám NYERGES ◽  
Máté ZÖLDY

Due to the new European emission norms internal combustion engines have to comply stricter rules. The new norms contain new requirements that were not included in previous regulations for example the decreased temperature of the cold start or the real driving emission part. The emission cycles for passenger vehicles are completely news, the stricter emission norms for commercial vehicles will follow them within a few years. Despite the increasing spread of alternative transmission systems in road transport Diesel engines are going to be remain in commercial vehicles in the next decades due to their good torque and fuel consumption performance. The emission of Diesel engines can be kept low by several way: by the modification of combustion processes, or by exhaust gas after treatment. To comply future regulations both of them seems to be necessary. By exhaust gas recirculation systems alternative Diesel combustion processes can be realized which can provide lower nitrogen-oxide emission and in several operation points also lower fuel consumption. Exhaust gas recirculation systems also can support the thermal management of a Diesel engine. To utilize the advantages of the recirculated exhaust gases a complex system is necessary to get a freedom in control possibilities: duel loop exhaust gas recirculated systems supplemented with supporter valves on the intake or on the exhaust side. In this paper a pressure and mass flow rate based control oriented engine model will be presented which contains high and low pressure exhaust gas recirculation systems and both of them are supported by exhaust brakes. The model considers four balance volumes and it has five state variables. The model is validated by an engine dyno measurements on a medium duty Diesel engine.


2018 ◽  
Vol 388 ◽  
pp. 1-13
Author(s):  
Luca Piancastelli ◽  
Eugenio Pezzuti ◽  
Stefano Cassani

The primary task in DI (Direct Injection) diesel engines design is the fulfilment of the required emission limits. This result should be achieved with acceptable power-to-rpm diagrams, acceptable fuel consumption, acceptable power density and affordable purchase and maintenance expenses. The most common approach to fulfil these requirements is the downsizing. In this case a significant increase in the crankshaft speed and boost pressure is unavoidable. In this way, an improvement in airflow through the redesign of the intake and exhaust geometry is obtained. Unfortunately, duct design is extremely difficult due to “Mach lock”. A further important boundary condition is due the injector inertia. The dynamic response improves with small injectors due to the Newton’s second law. Small injectors designed for unitary power of 15 to 70 HP are extremely common. Therefore, most of the research is centered on these injectors. Furthermore, their small inertia favors better opening and closing time. Nozzles number and position is also greatly influential on combustion performance. The larger surface of the spray reduces the gasification time of the droplets. For these reasons, multiple injectors systems may be used in large high pressure HSDI-CR (High Speed Direct Injection – Common Rail) diesels. Multi injection was commonplace in relatively large old diesels. This paper proposes new intake duct geometries for modern two-injectors-per-cylinder truck-size engines. For this purpose a new promising, patented concept is introduced. The study includes flow simulations during the intake phase. This patented geometry induces the presence of two extremely strong swirls approximately centered to the injectors, with excellent swirl coefficient and high flow rate. The use of swirl generators on the manifolds avoids the necessity to design helical intake ducts. This patented approach simplifies head design. Moreover, using a VG (Variable Geometry) arrangement for the volutes (swirl generators) it is possible to tune the swirl index at the optimum for every crankshaft velocity and every load. In this way, the vehicle fuel consumption is also reduced.


Sign in / Sign up

Export Citation Format

Share Document