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Both the shift from fossil to alternative fuels and the implementation of a pre-chamber combustion system allow for an increase in the efficiency of an internal combustion engine through optimizing its combustion process, while simultaneously reducing the engine-out emissions. The combination of alcohol-based fuels and pre-chamber combustion concepts has not been investigated on spark-ignition engines with high compression ratios in a passenger car size. This study presents investigations to show the potential in maximum achievable lean limit and net indicated efficiency. In particular, we present investigations of two alternative alcohol fuels on a direct-injection spark-ignition single-cylinder research engine for passenger car applications with a compression ratio of 16.4. The engine was operated with both an active and a passive pre-chamber, and the experimental results were compared to those of conventional spark-ignition operation. Direct injection was used for both the main combustion chamber and the pre-chamber. Methanol and ethanol were used as fuels for the main combustion chamber, whereas exclusively ethanol was used for the pre-chamber fueling. The performance of the alcohol fuels in all combustion configurations was evaluated in both part-load and high-load conditions. In particular, investigations of the combustion behavior over a variation of the excess air ratio at indicated mean effective pressures of 6 and 15 bar were performed. It can be concluded that with the use of methanol as fuel for the main combustion chamber, both higher excess air ratios and higher indicated efficiencies were achieved compared to the use of ethanol as the main combustion chamber fuel. In particular, a maximum net indicated efficiency of 48% at an excess air ratio of 2.0 was achieved with methanol. Moreover, active pre-chamber operation extended the lean limit to an excess air ratio of 2.3 compared to the maximum lean limit of 1.7 in passive pre-chamber operation.

The CBU type motorcycle (completely built up) had components imported from abroad. The advantages of handling a light motorbike, a large motor power and a DOHC engine. One of the weaknesses of which is the engine that heats up quickly even though it uses a radiator as the cooling system. In the performance test of the CBU Yamaha R6 and Honda CBR600F4I motorbike engines, the fuel was used for the Pertamax turbo type with an octane value of 98 to make the engine stable at high compression. The resulting performance of the gasoline motor is in the form of torque and power data using a dynamometer. How to see the performance data of a gasoline motor can make measurements on the crankshaft, input the temperature and output of the combustion system chamber as well as the ambient temperature. The research aims to see the performance data of the two machines. The method will produce experimental data analysis in graphs and tables. The biggest performance was obtained from the CBU type Honda CBR600F4I motorbike engine with Pertamax turbo fuel, namely with a torque of 46.74 Nm, at 13,630 rpm and a power of 114.48 Hp, while the Yamaha R6 motorbike engine with Pertamax turbo fuel only had a torque of 40.65 Nm, at 12,600 rpm and a power of 90.81 Hp

This work was predicated on the design and costing of a packed column absorber required to remove SO2 from an air/SO2 mixture. The absorber is intended to be developed into an already existing combustion system as a retrofit. The gas flow rate basis of the computation was 40,000Kg/h. The Onda Method was used to estimate the column height as 9m and the column diameter as 2.5m while the column wall thickness as well as the domed head thickness was found to be 9mm using the BS 5500 Standard Method. In order to limit expenses, H2O was utilized as the absorber solvent and a flow rate of 29.5Kg/s to limit solvent usage. A pressure drop of 20mmH2O/m was assumed in the design with metal pall rings of diameter 51mm and surface area of 102m2/m3 chosen as the packing material. The study estimated a profound $306,559.87 as the cost of the absorber required to remove 95% SO2 content from the combustion waste stream.

Within the next thirty years the evolutionary approach to aero engine development will struggle to keep abreast with increasingly stringent environmental targets. Therefore radical approaches to aero-engine development in terms of energy savings need to be considered. One particular concept involves the inclusion of a pressure-rise combustion system, within the architecture of an aero-engine, to provide additional shaft power. The nutating disc engine concept is a strong contender due to its power density. The feasibility of the nutating disc engine has been previously investigated for unmanned vehicle applications. However, this paper investigates the performance benefits of incorporating a nutating disc core in a larger geared open rotor engine for a potential entry in to service in 2050. In addition, a methodology is presented to estimate the size and weight of the nutating disc core. This methodology is pivotal in determining the overall performance of the novel aero-engine cycle. The outcome of this study predicts a potential 9.4% fuel burn benefit, over a state of the art geared open rotor in the year 2050. In addition, the sensitivity of the nutating disc design variables highlights the possible fuel burn benefits compared against a comparable year-2000 aircraft mission.

TMG (TOYOTA Motorsport GmbH) and FEV have jointly conducted a concept study on environmentally friendly engine with indicated thermal efficiency (ɳinet) of 46% and low emissions while fulfilling high-performance criteria i.e. specific power of 103 kW/l and low end torque (LET) of 2.3 MPa BMEP at 2000rpm. An ultra lean-burn combustion concept has been designed by means of 1D and 3D MBD (Model Base Development) methods and subsequently validated experimentally by a single cylinder TC GDI engine as a technology demonstrator in order to fulfill the requirements of both environmental sustainability and fun to drive in passenger cars.

As one of the core components of gas turbines, the combustion system operates in a high-temperature and high-pressure adverse environment, which makes it extremely prone to faults and catastrophic accidents. Therefore, it is necessary to monitor the combustion system to detect in a timely way whether its performance has deteriorated, to improve the safety and economy of gas turbine operation. However, the combustor outlet temperature is so high that conventional sensors cannot work in such a harsh environment for a long time. In practical application, temperature thermocouples distributed at the turbine outlet are used to monitor the exhaust gas temperature (EGT) to indirectly monitor the performance of the combustion system, but, the EGT is not only affected by faults but also influenced by many interference factors, such as ambient conditions, operating conditions, rotation and mixing of uneven hot gas, performance degradation of compressor, etc., which will reduce the sensitivity and reliability of fault detection. For this reason, many scholars have devoted themselves to the research of combustion system fault detection and proposed many excellent methods. However, few studies have compared these methods. This paper will introduce the main methods of combustion system fault detection and select current mainstream methods for analysis. And a circumferential temperature distribution model of gas turbine is established to simulate the EGT profile when a fault is coupled with interference factors, then use the simulation data to compare the detection results of selected methods. Besides, the comparison results are verified by the actual operation data of a gas turbine. Finally, through comparative research and mechanism analysis, the study points out a more suitable method for gas turbine combustion system fault detection and proposes possible development directions.

The first Siemens AG SGT5-4000F was introduced in 1996. Since then, the combustion system was improved in several evolutionary steps in order to enhance the engine performance and emission requirements. Especially emissions requirements will become more challenging in the future as the typical limits will likely drop from 25ppm NOx to 15ppm or even single digit. In addition to clean power solutions, the market simultaneously demands increased operational flexibility in terms of load gradients, fuel flexibility (special fuels, hydrogen addition) and turndown capability. The SGT5-4000F fleet consists of more than 350 units in operation with ∼20Mio accumulated operating hours. Retrofit ability to the fleet is therefore an important aspect of the combustion system development. The paper reports upon the development of the latest improvements of the combustion system of SGT5-4000F engines, which have been achieved by application of the latest numerical design tools, advanced statistical machine learning techniques and utilization of additive manufacturing. Results from testing and validation of the modifications at the Siemens Clean Energy Center (CEC) for stand-alone combustion tests and Berlin Test Facility (BTF) for full scale engine tests will be presented. The system improvement includes aero-dynamic, fuel / air mixing and combustor cooling air management optimizations, which are the typical focus areas for lean premixed combustion systems in gas turbines.

The focus of research is shifting toward development of new engine fuels for optimized combustion systems. The altered chemical structure of these new fuels may impact their thermal decomposition c...

In this study confirmed the reduction effect of pollutant by applying Fi-EGR and FPI-EGR to hybrid combustion system realizing premixed flame and non-premxied flame at once. The results showed that NOx emission index decreased significantly in case of adopting EGR. Additionally, the hybrid combustion system with EGR resulted in a better performance compared to usual non-premixed combustion system such that it can reduce NO x emission at equivalent EGR ratios. Especially, in the case of 25% of FI-EGR ratio at hybrid combustion system that the ratio of non-premixed and premixed is 50 : 50, NOx emission index reduction rate was about 59% compared to NO x emission of non-premixed combustion system without EGR and in the case of 15% of FPI-EGR ratio at hybrid combustion system that the ratio of non-premixed and premixed is 70 : 30, NO x emission index reduction rate was about 48% compared to NO x emission of hybrid combustion system without EGR. Key words : Hybrid combustion, Exhaust gas recirculation (EGR), NO

Chinese fuel consumption regulation will be more and more stricter. China will implement Stage III fuel consumption regulation by the end of 2015. First Automobile Works (FAW) has developed a new GDI-T gasoline engine to meet this fuel consumption regulation for A-class car. The rated power of this engine is 100 kW, and maximum torque of this engine is 220 Nm. The BSFC at 2000 r/min-2 bar BMEP reaches 373 g/kWh. The acceleration time from 0 to 90% maximum load at 1500 r/min is less than 1.7 s. Matching with the kerb weight 1265 kg of one A-class car, maximum vehicle speed is 210.5 km/h and acceleration time of 0–100 km/h is 10 s. NEDC-integrated fuel consumption is 5.85 L/100 km, which is 15% lower than Chinese Stage III fuel consumption regulation meanwhile meeting the dynamic performance of the vehicle.

Extension of gas fuel flexibility of a current production SGT-400 industrial gas turbine combustor system is reported in this paper. A SGT-400 engine with hybrid combustion system configuration to meet a customer's specific requirements was string tested. This engine was tested with the gas turbine package driver unit and the gas compressor-driven unit to operate on and switch between three different fuels with temperature-corrected Wobbe index (TCWI) varying between 45 MJ/m3, 38 MJ/m3, and 30 MJ/m3. The alteration of fuel heating value was achieved by injection or withdrawal of N2 into or from the fuel system. The results show that the engine can maintain stable operation on and switching between these three different fuels with fast changeover rate of the heating value greater than 10% per minute without shutdown or change in load condition. High-pressure rig tests were carried out to demonstrate the capabilities of the combustion system at engine operating conditions across a wide range of ambient conditions. Variations of the fuel heating value, with Wobbe index (WI) of 30 MJ/Sm3, 33 MJ/Sm3, 35 MJ/Sm3, and 45 MJ/Sm3 (natural gas, NG) at standard conditions, were achieved by blending NG with CO2 as diluent. Emissions, combustion dynamics, fuel pressure, and flashback monitoring via measurement of burner metal temperatures, were the main parameters used to evaluate the impact of fuel flexibility on combustor performance. Test results show that NOx emissions decrease as the fuel heating value is reduced. Also note that a decreasing fuel heating value leads to a requirement to increase the fuel supply pressure. Effect of fuel heating value on combustion was investigated, and the reduction in adiabatic flame temperature and laminar flame speed was observed for lower heating value fuels. The successful development program has increased the capability of the SGT-400 standard production dry low emissions (DLE) burner configuration to operate with a range of fuels covering a WI corrected to the normal conditions from 30 MJ/N·m3 to 49 MJ/N·m3. The tests results obtained on the Siemens SGT-400 combustion system provide significant experience for industrial gas turbine burner design for fuel flexibility.

F-class gas turbines comprise a major part of the heavy-duty gas turbine power generation fleet worldwide, despite increasing penetration of H/J class turbines. F-class gas turbines see a wide range of applications, including simple cycle peaking operation, base load combined cycle, demand following in simple or combined cycle, and cogeneration. Because of the different applications, local power market dynamics, and varied emissions regulations by region or jurisdiction, there is a need for operational flexibility of the gas turbine and the combustion system. In 2015, GE introduced a DLN2.6+ combustion system for new and existing 7F gas turbines. Approximately 50 are now in operation on 7F.04 and 7F.05 turbines, combining for nearly 150,000 fired hours. The system has been demonstrated to deliver 5 ppm NOx emissions @ 15% O2, and it exhibits a wide window of operation without significant thermoacoustic instabilities, owing the capability to premixed pilot flames on the main swirl fuel-air premixers, low system residence time, and air path improvements. Based on the success on the 7F, this combustion system is being applied to the 6F.03 in 2018. This paper highlights the flexibility of the 7F and 6F.03 DLN2.6+ combustion system and the enabling technology features. The advanced OpFlex* AutoTune control system tightly controls NOx emissions, adjusts fuel splits to stay clear of instabilities, and gives operators the ability to prioritize emissions or peak load output. Because of the low-NOx capability of the system, it is often being pushed to higher combustor exit temperatures, 35°C or more above the original target. The gas turbine is still meeting 9 or 15 ppm NOx emissions while delivering nearly 12% additional output in some cases. Single-can rig test and engine field test results show a relatively gentle NOx increase over the large range of combustor exit temperature because of the careful control of the premixed pilot fuel split. The four fuel legs are staged in several modes during startup and shutdown to provide robust operation with fast loading capability and low starting emissions, which are shown with engine data. The performance of a turndown-only fueling mode is highlighted with engine measurements of CO at low load. In this mode, the center premixer is not fueled, trading the NOx headroom for a CO emissions benefit that improves turndown. The combustion system has also demonstrated wide-Wobbe capability in emissions compliance. 7F.04 engine NOx and dynamics data are presented with the target heated gas fuel and also with cold fuel, producing a 24% increase in Modified Wobbe Index. The ability to run unheated fuel at base load may reduce the start-up time for a combined cycle plant. Lastly, there is a discussion of a new OpFlex* Variable Load Path digital solution in development that will allow operators to customize the start-up of a combined cycle plant.

In this study, the characteristics of NOx emissions for CH4/air non-premixed flames using EGR (exhaust gas recirculation) methods were investigated using the AI-EGR (air-induced-EGR) and FI-EGR (fuel-induced-EGR) methods. For the fundamental experiment, coaxial non-premixed flames were verified using the non-premixed mode in a changeable EGR hybrid combustion system. For the numerical simulation, the 2-D commercial FLUENT program was used to verify the distributions of the flame temperature and mole fraction of the NO emissions. Additionally, the swirling non-premixed flames were tested to investigate a practical combustion system. Based on experimental results, the reduction rates of EI NO X for the FI-EGR method and the AI-EGR were approximately 29% and 28% for an EGR ratio of 20% and 25%, respectively, which represented the maximum range needed to generate a stable flame. Based on numerical results, the FI-EGR method was determined to be more effective than the AI-EGR method in reducing NOx emission because the high temperature region and the OH distribution region of the FI-EGR method were narrower. According to the results from the swirling flames, the reduction rates of EI NO X for the FI-EGR method and the AI-EGR were approximately 49% and 45% for an EGR ratio of 15% and 25%, respectively.

This paper introduces two modeling methods of the incinerator’s combustion control system. Aiming at the features of the control system which apply to the incinerator’s combustion system, this paper uses the techniques of system identification which are based on the least square method and the neural network, introduces two ways of model identification in the incinerator’s combustion control system, then they can be helpful for the following design of the control system. By simulating the model of the incinerator’s combustion control system, desired results can be obtained for following the track of the main control target-temperature.

The world is currently undergoing a shift in the power industry with an increase in the amount of electrical power being generated from natural gas. This is being driven, in part, by the increase in availability of natural gas derived from shale gas and the reduction in global natural gas prices. In parallel, there is a second trend; a shift of new gas turbines installations to higher efficiency F and HA-class gas turbine combined cycle platforms. Supporting these industry trends, GE’s DLN 2.6+ combustion system, which is available for the 7F, 9F, 7HA, and 9HA gas turbines offers a high degree of operational and fuel flexibility. The latest evolution of this combustion technology for GE’s 7F gas turbines has been commissioned on 25 units, including new units and upgrades to existing turbines. The increased fuel and operational flexibility of this system is aided by GE’s advanced control systems that includes a high fidelity digital twin. This paper details recent developments of the DLN 2.6+ combustion system as well as validation examples for both the DLN 2.6+ and the digital twin controls system.

In 1893 Rudolf Diesel laid the cornerstone for the later triumphal procession of his engine concept at least in the heavy duty business. With the first serial production engine running in 1897, the huge benefit of this combustion system was demonstrated

Modification of combustion system from indirect injection (IDI) to direct injection (DI) was carried out on the two cylinder diesel engine, followed with tests for performance and emission. The modification from IDI to DI was conducted on a two cylinder diesel engine by removing the pre-chamber from the inside of the cylinder head, replacing the injector and its position to the top of the combustion chamber directly and also replacing the original piston with a piston that has a bowl on the crown. Performance and emission tests were conducted on 1,500 rpm with loads that vary from 0, 10, 20, 30, 40, 50, to 60 Nm. The investigation results of the diesel engine modification from IDI to DI showed several interesting phenomena. Further research is needed in order to increase the engine performance and reduce its emission.

Setting engine emission targets to meet diesel car requirements is particularly important in engine performance development phase. Many researches are focused on associating vehicle performance with engine targets, but most work is done by testing, which is time and cost consuming, furthermore, the relationship of vehicle and engine will change when either engine or vehicle changes. A GT-Drive model to simulate New European Driving Cycle (NEDC) for passenger car is developed and calibrated by testing data, model precision is controlled within 5%. Time distribution of engine operating conditions when car running NEDC cycle has been analyzed, 10 critical major engine operating points are summarized according to running time proportion. Emission of NOx and smoke control regions containing these 10 points for target engine are set. Vehicle emissions are simulated and evaluated during engine development after engine performance test data are got, and engine combustion system layout and calibration are adjusted until vehicle targets are met. Vehicle is tested in chassis dynamometer finally, the testing results show a good agreement with the simulated results with an error of less than 5%, which proves that the emission value exchange of vehicle and engine is reliable. Performance target decomposition method for passenger car diesel presented can greatly shorten the development cycle and save costs.

According to the multivariable coupling, large delay, nonlinear, time-varying and other difficulties of a thermal power plant boiler combustion system, a kind of technology based on fuzzy control of a thermal power plant boiler combustion system was presented. Fuzzy control technology was used to research and determine fuzzy control rule tables. Multivariable static and dynamic models were given to boiler combustion system. Results of simulation show that boiler combustion system control precision was effectively improved and good effects in production and application were got.

To carry out product virtual design for diesel engine combustion system, the top-down method is used. The diesel engine combustion system is designed and each part is modeled in Pro/E. Pro/E is a solid modeler and this offers considerable advantage for solid model creation. Normally, the geometry is first sketched in 2-D and then extruded in the third direction to generate a 3-D model. In Pro/E, it is important to first create the base geometry. The base geometry is that captures the design intent of the part to be modeled. This base geometry can be created using either the EXTRUDE or the REVOLVE options. Once this base geometry has been created, additional features like holes, rounds, chamfers, fillets, ribs, etc can be added in the finishing stages of the part creation. The center of the bowl does not coincide with the center of the cylinder due to the presence of valve pockets. The obvious advantage of this configuration is that is gives the true geometry of the piston and the connecting rod ports can be accommodated when the piston is at the top dead center.

In the modern era, combination of several sensor types to determine the vehicle exhaust content is needed. Dangerous and toxic vehicle exhaust, such as HC, CO, CO2 and NO, needs to be controlled to reduce air pollution level. The vehicle exhaust content level can be measured by applying a combination of several sensors. In this research, a tool to detect vehicle combustion system condition based on vehicle exhaust content level has been designed. The tool combines several sensors, they are: TGS22001 sensor, TGS2602 sensor and MG811 sensor. Bluetooth HC-05 technology is also used to support Android-based information system. The combination of these technologies makes all of gas detection result can be known in real time and updated via smartphone. Arduino UNO R3 module is used to control all systems (gas- sensor-ADC-interface-Bluetooth-display). The results of combustion level test conducted on 15 motorcycles are: 8 motorcycles are bad, 4 motorcycles are medium and 3 others are good.

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Hydrogen is regarded as a future energy carrier. Within the H2BVplus research project sponsored by the Austrian Federal Ministry for Transport, Innovation and Technology (BMVIT), a high-efficiency combustion system has been developed for passenger car hydrogen engines by the Institute of Internal Combustion Engines and Thermodynamics of Graz University of Technology in collaboration with BMW Group Research and Technology. The conventional diesel combustion process served as a template.

Low speed driving profiles, like city ones, are very critical for passenger cars equipped with Diesel particulate filters (DPF). The main problem one must face is the significant oil dilution increase when using standard in-cylinder post-injection strategies. Following the experience gained in the field with the 1.5-dCi- Euro-4-engine with 78 kW equipped with DPF and exhaust fuel injection system (EFI), this device has been further optimized in the view of the new Euro 5 Renault’s engine family. In comparison to the other solutions to reduce oil dilution (new combustion system design, innovative in-cylinder injection strategy) this system has demonstrated a high autonomy on urban cycles with a considerable improvement of the fuel consumption at low loads.

To strengthen the appeal of Hyundai/Kia’s premium SUVs, a new V6 3 l diesel engine has been developed. Its combustion system provides both high performance for driving comfort and potential for Euro 4 emission standard. This engine provides a foundation for coping with the next generation Euro 5 emission standards by adopting advanced combustion and after-treatment systems while development work has already started on the application of urea injection NOx after-treatment system in order to meet the US Tier 2 Bin 5 emission standard.

MAN has developed a new V8 engine for the 16-l class with an output of 500 kW and 3,000 Nm of torque for its TGX and TGS ranges of heavy trucks. To reduce NOx, MAN has applied an SCR system with AdBlue injection. This article describes the engine concept, the design of the main components, the development of vehicle-specific add-on parts and the work carried out to optimise the combustion system and exhaust aftertreatment.

Due to changing economic, technical and social environments and resulting customer demands, future vehicle drive systems will be required to have lower pollutant emissions and greater efficiency, leading to a CO2 reduction. Combining the advantages of the petrol and diesel combustion processes is a way of achieving these objectives. In the Group Research — Drive Systems of Volkswagen AG, this implementation is referred to as the Combined Combustion System CCS.

Downsizing and turbocharging combined with direct injection are regarded as a key technology to allow petrol engines to cope with the challenges of fuel economy enhancement and driveability improvement. Stratified part load operation can be a solution even for downsized engines if the maximum fuel economy potential of a spray-guided petrol direct injection combustion system is available, as shown by Ford’s analysis of the stratified window size impact on cycle fuel economy.

In order to investigate the influence of combustion chamber geometry on the formation of air-fuel mixture in diesel engine, a new double-layer diffluent combustion system for DI diesel engine was proposed which had a collision platform with circular oriented-surface. The mixing process of the fuel spray and air in this combustion chamber is modelled and numerical simulation is executed by the software AVL FIRE. The simulation results indicate that the fuel spray distribution becomes more uniformed for the double-layer diffluent combustion system than that of the ω combustion system. It can be concluded that the combustion chamber geometry put important effect on the formation of air-fuel mixture in combustion chamber. Keywords-diesel engine; double-layer diffluent combustion system; combustion chamber geometry; numerical simulation

This is the first engine family specifically designed for light and medium commercial vehicles to be produced under the joint Ford Motor Company/PSA Peugeot Citroen Diesel engine co-operation agreement. Although the new engine is based on an existing engine architecture, it introduces a number of technical innovations, raising the bar even higher for engine technology in the commercial vehicle sector. Part of the engine development has focused on optimising the combustion system and was led by the engineers of the Ford Research and Advanced Engineering Centre FFA in Aachen, Germany. The new engines produce engine-out emissions that are well within the stringent limits given by the EU4 Light Duty Truck (LDT) emissions standard for all of the vehicle applications, whilst maintaining good fuel economy.

Engine series development gets fast and in-time confirmation if a combustion system is as exhaustively exploited as concept design and pre-development have promised. Combustion deficiencies not only compromise performance and emissions, they first of all leave noticeable traces in the signature of the flame. AVL’s Visiolution technology systems enable the series development engineer to read these traces and to use standardised flame analysis tests for fast and precise performance and emissions development.

This paper presents a technique for diagnosis of a class of engine faults, which adversely affect the combustion efficiency of a diesel generator set. The diagnosis is made by combining the evidence of two separate estimations of engine load with the outputs from a predictive fuzzy model of engine speed. Certain faults affect the periodicity of the engine speed signal. The variation in periodicity means that the load estimation from power spectral density of the speed signal is not robust. This problem is countered by implementing a reference model to predict speed fluctuations with respect to crank angle. This model has the additional benefit that its output may be used to detect periodic fault symptoms in the speed signal, thereby leading to identification of the individual cylinder affected by the fault. A fuzzy rule based system has been developed to diagnose faults based on the load estimations and the residuals obtained from the reference model. Testing the diagnostic system with data from the normal, and two other separate engine fault conditions, resulted in a classification success rate greater than 90 per cent in each case. A further benefit is reported where the combination of evidence from the three sources effectively validates the load estimation, which may then be used to infer faults in other subsystems.