Journal articles: 'Perfect combustion'

1

Tuccar, Gökhan, Göktürk Memduh Özkan, and Kadir Aydın. "Determınatıon of Atomızatıon Characterıstıcs of a Dıesel Injector." Applied Mechanics and Materials 799-800 (October 2015): 826–30. http://dx.doi.org/10.4028/www.scientific.net/amm.799-800.826.

Full text

Abstract:

Atomization of liquid fuels is very important topic for combustion studies since it enhances air/ fuel mixing process and therefore ensures perfect combustion. With today’s common diesel injectors, fuel is directly injected into the combustion chamber with extremely high pressures which exceed 1300 bar in order to obtain perfect atomization. However, these high injection pressures unfortunately create some problems in the injection system such as cavitation erosion which may lead to mechanical failure. Introducing of air into the injector prior to combustion will increase fuel atomization, provide more complete combustion, enhance fuel economy and results in lower engine emissions. The aim of this study is to investigate atomization behaviour of a newly introduced diesel engine which mixes air and fuel prior to combustion chamber.

APA, Harvard, Vancouver, ISO, and other styles

2

Andrizal, Rusfandi, and Rivanol Chadry. "Implementasi Metoda Sum Squared Error untuk Identifikasi Kategori Pembakaran Mesin Sepeda Motor 4 Tak Bahan Bakar Bensin." Jurnal Ilmiah Poli Rekayasa 11, no. 2 (April 15, 2016): 1. http://dx.doi.org/10.30630/jipr.11.2.22.

Full text

Abstract:

Motorcycles with injection system uses engine scanner tool as a reference for a mechanic when performing a tune-up to find out and get the engine firing conditions were perfect. Unlike the motorcycle carburetor system, relying only on the experience of a mechanic. If using tools, usually using exhaust emission analyzer which only serves to measure the levels of elements and compounds and exhaust emissions and it can not be used to identify the condition of the combustion engine. Besides, not all the workshops have it, just a certain manufacturer authorized workshops, garages and a large scale or related government agencies that have it. There are two categories of combustion engine, the first engine combustion conditions are not perfect and complete combustion conditions. Perfect engine combustion conditions is needed so that maximum engine performance with an efficient use of fuel. This study aims to make a device that is capable of detecting the condition of combustion 4-stroke motorcycle carburetor system using the method of sum square error (SSE) through the value of the data patterns of exhaust emissions based gas sensors. The study, of the five categories of motorcycles with the manufacturer, type and year of manufacture of different shows that, the system made capable of identifying categories of combustion engine based on the SSE on the identification and reference set. The success rate of identification detection system performs the complete combustion of 89.33% and 97.99% of incomplete combustion.

APA, Harvard, Vancouver, ISO, and other styles

3

Arora, Nidhi, and Swati Mehta. "Air fuel ratio detector corrector for combustion engines using adaptive neuro-fuzzy networks." An International Journal of Optimization and Control: Theories & Applications (IJOCTA) 3, no. 2 (May 29, 2013): 85–97. http://dx.doi.org/10.11121/ijocta.01.2013.00152.

Full text

Abstract:

A perfect mix of the air and fuel in internal combustion engines is desirable for proper combustion of fuel with air. The vehicles running on road emit harmful gases due to improper combustion. This problem is severe in heavy vehicles like locomotive engines. To overcome this problem, generally an operator opens or closes the valve of fuel injection pump of locomotive engines to control amount of air going inside the combustion chamber, which requires constant monitoring. A model is proposed in this paper to alleviate combustion process. The method involves recording the time-varying flow of fuel components in combustion chamber. A Fuzzy Neural Network is trained for around 40 fuels to ascertain the required amount of air to form a standard mix to produce non-harmful gases and about 12 fuels are used for testing the network’s performance. The network then adaptively determines the additional/subtractive amount of air required for proper combustion. Mean square error calculation ensures the effectiveness of the network’s performance.

APA, Harvard, Vancouver, ISO, and other styles

4

NAKAMURA, Masamichi, Kazuhiro YAMAMOTO, and Hiroshi YAMASHITA. "303 Simulation on Soot Combustion in Diesel Exhaust Gas Perfect Burning System." Proceedings of the Symposium on Environmental Engineering 2008.18 (2008): 270–71. http://dx.doi.org/10.1299/jsmeenv.2008.18.270.

Full text

APA, Harvard, Vancouver, ISO, and other styles

5

Beccantini, A., and E. Studer. "The reactive Riemann problem for thermally perfect gases at all combustion regimes." International Journal for Numerical Methods in Fluids 64, no. 3 (September 8, 2009): 269–313. http://dx.doi.org/10.1002/fld.2149.

Full text

APA, Harvard, Vancouver, ISO, and other styles

6

Komatsu, Teruya, Reiko Kaji, Shun Okazaki, Ikuko Miyawaki, Kyousuke Ishihara, and Yutaka Takahashi. "Endotracheal Tube Ignition During the Intratracheal Laser Treatment." Asian Cardiovascular and Thoracic Annals 16, no. 6 (December 2008): e49-e51. http://dx.doi.org/10.1177/021849230801600623.

Full text

Abstract:

We experienced the combustion of the endotracheal tube during a bronchoscopic potassium titanyl phosphate laser resection of an intratracheal metastatic tumor. Some preventive precautions have been reported, however, none of them are absolutely perfect. We report the rare occurrence of tracheal tube ignition, preventive measures and treatment strategies for the resultant airway burn.

APA, Harvard, Vancouver, ISO, and other styles

7

Yuniarto, Winoko Agus, Hertomo Bambang, and Nurhadi Nurhadi. "PENGGUNAAN HYDRO-CRACK SYSTEM SEBAGAI UPAYA MENINGKATKAN KINERJA MESIN." ROTOR 11, no. 2 (November 1, 2018): 1. http://dx.doi.org/10.19184/rotor.v11i2.9323.

Full text

Abstract:

The use of hydro-crack systems in combustion motors in addition to functioning to improve exhaust emissions and improve engine performance through the combustion process. Perfect combustion can be adjusted during the combustion process. The purpose of the study was to determine the select magnitude of power increase, decrease fuel consumption and increase the average effective pressure and rotation of the use of 92 octane fuel without HCS. The method of testing engine performance in obtaining data is constant speed (v boarding) based on ISO 1585. Subsequent data signifies presented in a graphical form which is then calculated by statistics. Power increased 2.83hP and bmep 43.19kPa at 4000rpm, sfc dropped 0.0358kg / hP. Hours at 1000rpm and rose by 43.19kPa, when using 92 octane fuel against the standard. When using octane 95 with HCS the power rises 7.95hP at 4000rpm, buys 28.42 kPa when 4500 and sfc drop 0.0537kg / hp. Hours at 1000rpm Keywords: power, fuel consumption, effective average pressure, octane value, hydro-crack system

APA, Harvard, Vancouver, ISO, and other styles

8

Xue, Gang, Xue Fang Zhang, Sai Fei Wang, and Chao Yue Zhao. "Preparation and Characterization of Perovskite-Type Oxide Catalysts for Combustion of Methane." Advanced Materials Research 427 (January 2012): 77–81. http://dx.doi.org/10.4028/www.scientific.net/amr.427.77.

Full text

Abstract:

A series of rare earth perovskite-type oxides La09Sr0.1Co0.9Mn0.1O3La08Sr0.2Co0.8Mn0.2O3and La05Sr0.5Co0.5Mn0.5O3were prepared along the sol-gel method and characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (SEM), transmission electron microscopy techniques (TEM) and catalytic activity measurement for combustion of CH4. The results indicated that a perfect crystal structure of perovskite was formed and La3+and Co3+ions were partly replaced by Sr2+and Mn3+ions, respectively, and perovskite-type oxides were composed of nanocrystals with particle size of 20~50nm. The catalytic activity for the combustion of CH4 was evaluated and La05Sr0.5Co0.5Mn0.5O3exhibited best performance with the temperature of 50% and 90% conversion efficiency of 723K and 833K.

APA, Harvard, Vancouver, ISO, and other styles

9

Riza, Abrar, Hansel Hansel, and Harto Tanujaya. "PENGARUH UKURAN ATOMISASI BAHAN BAKAR TERHADAP UNJUK KERJA MOTOR BAKAR." POROS 15, no. 2 (January 6, 2018): 92. http://dx.doi.org/10.24912/poros.v15i2.1269.

Full text

Abstract:

Abstract: The size of droplet affects the evaporation of the fuel. The greater the size of droplet is also the energy of fuel evaporation. The evaporation energy is directly proportional to the size of the droplet and oxidation must be mixed homogeneously. Mixing conditions in the combustion process affect the rate of combustion. One of the conditions of combustion is the droplet to the vapor. The more perfect the evaporation process the better the combustion process. This study saw the success of combustion due to the size of droplet on the performance. The droplet produced by atomization in the form of liquid granules. The size of atomization is the determinant of burning success. The four-stroke Otto engine performance depends on the size of the atomization in order to mix well with the oxidant during combustion process. The results of the research characteristic of the machine are due to the influence of the size of the droplet seen from the generated power, torque and thermal efficiency. Characteristic features increase with decreasing the size of the droplet. Torque increased 7.9%, power generated increased 7%, and thermal efficiency increased up to 7.3%. The results of this study show size of the droplet can improve the performance of engine.

APA, Harvard, Vancouver, ISO, and other styles

10

Priambadi, I. Gusti Ngurah, I. Ketut Gede Sugita, A. A. I. A. Sri Komaladewi, Ketut Astawa, and I. Wayan Bandem Adnyana. "Redesign Combustion Air Shelter of the Furnace to Improve the Performance in Melting Bronze for Manufacturing Gamelan." Applied Mechanics and Materials 776 (July 2015): 355–60. http://dx.doi.org/10.4028/www.scientific.net/amm.776.355.

Full text

Abstract:

Gamelan Bali is a set of Balinese traditional musical instruments used to accompany a series of cultural and religious ceremonies or performances. The existence of gamelan has been famous to foreign countries. Therefore, gamelan is not only produced for national orders but also for international orders. Almost 75% of gamelan production process is done using traditional method, namely: smelting, forging, grinding (Sruti) to get the basic tone, and assembly. Smelting process uses traditional furnace, where combustion air is blown from the blower through the injector into the combustion chamber of melting furnace. Open model furnace is used so that the heat generated in the combustion of the fuel is not perfect and it consumes more fuel. This condition, of course, impacts on pollutant factors produced in the combustion process and production cost that is relatively high. To minimize that problem, a change in the combustion air shelters form is done. The use of this method in the smelting process is expected to reduce the production cost, especially in fuel use and to reduce pollutants produced in the combustion process. Studies have shown that the application of the above method reduces the fuel consumption up to 20%. The decrease in the fuel consumption due to the fuel (charcoal) is wrapped by more air, thus it makes the fuel combustion process work better.

APA, Harvard, Vancouver, ISO, and other styles

11

Irwansyah, Irwansyah, Muhammad Arsad Al Banjari, and Feddy Wanditya Setiawan. "The Effect Of Use Various Types Cables Spark Plugs To 108cc Scooter Machine Performance." JMIO: Jurnal Mesin Industri dan Otomotif 2, no. 01 (January 20, 2021): 1–6. http://dx.doi.org/10.46365/jmio.v2i01.405.

Full text

Abstract:

Ideally, the combustion system system in the combustion chamber, this is an alarm in order to get the right combustion results and of course will make the motorcycle power with the right fuel consumption too. There are at least 3 (three) important factors that must be met by the combustion system in the combustion motorbike, especially for gasoline-type automatic motorbikes. These three factors include the existence of an ideal fuel and air mixture (good air-fuel mixture), the right timing of business performance in producing spark plug spark quality (good spark) and good combustion chamber (good compression). An air-fuel mixture that can produce a homogeneous mixing of fuel and air. The acquisition of perfect combustion is directly proportional to the quality of a good type of spark plug cable. The ability of the type of spark plug cable must be able to support high electric current processes to produce the ideal spark. In this study, the type of business cable used is the brand that is in the market, namely proteck, extreme, hitachi and standard cable types. Performed variation testing 4 (four) types of spark plug cables. The test results show the best engine performance of a gasoline-fueled automatic motorbike using extreme spark plug cables, with a torque of 5,669 Nm at 7854 rpm and a power of 6,252 hp at 7854 rpm

APA, Harvard, Vancouver, ISO, and other styles

12

Boretti, Alberto. "Advances in Diesel-LNG Internal Combustion Engines." Applied Sciences 10, no. 4 (February 14, 2020): 1296. http://dx.doi.org/10.3390/app10041296.

Full text

Abstract:

Diesel-LNG internal combustion engines (ICEs) are the most promising light and heavy-duty truck (HDT) powering solution for a transition towards a mixed electric-hydrogen renewable energy economy. The diesel-liquid CH4 ICEs have indeed many commonalities with diesel-liquid H2 ICEs, in the infrastructure, on-board fuel storage, and injection technology, despite the fact H2 needs a much lower temperature. The paper outlines the advantages of dual fuel (2F) diesel-LNG ICEs developed adopting two high-pressure (HP) injectors per cylinder, one for the diesel and one for the LNG, plus super-turbocharging. The diesel-LNG ICEs provide high fuel energy conversion efficiencies, and reduced CO2, PM, and NOx emissions. Super-turbocharging permits the shaping of the torque curve while improving acceleration transients. Diesel-LNG ICEs may also clean up the air of background pollution in many polluted areas in the world. Computational results prove the steady-state advantages of the proposed novel design. While the baseline diesel model is a validated model, the 2F LNG model is not. The perfect alignment of the diesel and diesel-LNG ICE performances proven by Westport makes however the proposed results trustworthy.

APA, Harvard, Vancouver, ISO, and other styles

13

Aliyu, Aminu Safana, Nurhayati Abdullah, Fauziah Sulaiman, and Sadik Umar. "Combustion characteristics of palm pressed fibres biochar and sub-bituminous Malaysian coal." Malaysian Journal of Fundamental and Applied Sciences 14, no. 3 (September 3, 2018): 334–37. http://dx.doi.org/10.11113/mjfas.v14n3.937.

Full text

Abstract:

In this research, the combustion properties of coal and biochar were investigated and compared to identify the potentiality of biochar for coal replacement application. Biochar is derived from the pyrolysis of palm pressed fibre (PPF) at 400 oC. Thermogravimetric analysis (TGA) was used to study the combustion profiles of the materials. The biochar and coal were combusted via thermogravimetric analysis from ambient temperature to 800 oC at 10 oCmin-1 of heating rate. From the results, biochar showed the high calorific value of 27.30 MJkg-1compared to that of coal 26.21 MJkg-1. Furthermore, biochar comprised the greater content of carbon and fixed carbon. Although, during combustion, coal releases high heat of 0.052 W than biochar which gave 0.049 W. This reveals that the biochar produced from PPF can be a perfect competitor against coal for heat generation. This finding could assist in promoting the application of biomass as an alternative to fossil fuel.

APA, Harvard, Vancouver, ISO, and other styles

14

Ulfiana, Andi, Tatun Hayatun Nufus, Emir Ridwan, Arifia Ekayuliana, Cecep Slamet Abadi, Asep Apriana, and Iwan Susanto. "A study of bioethanol fuel characteristics in the combustion chamber of gasoline engine using magnetization technology." Eastern-European Journal of Enterprise Technologies 1, no. 6 (109) (February 10, 2021): 72–76. http://dx.doi.org/10.15587/1729-4061.2021.224235.

Full text

Abstract:

Bioethanol is a renewable energy that can replace gasoline, which will run out in the future. This study investigates the influence of magnetization of bioethanol fuel on the fuel combustion temperature in the combustion chamber of a gasoline motor. The fuel used is bioethanol with a composition of E0 (pure gasoline), E10 (10 % bioethanol+90 % gasoline), E20 (20 % bioethanol+80 % gasoline), E30 (30 % bioethanol+70 % gasoline), E40 (40 % bioethanol+60 % gasoline). The fuel passed through the magnet with a magnetic variation of 647.15 Gauss, 847.25 Gauss, 1419.57 Gauss. The temperature sensor used is a K-type thermocouple. The temperature sensor was inserted in the combustion chamber to measure the combustion chamber temperature. The thermocouple data were recorded in Microsoft Excel on a computer using the LabVIEW program via NI-USB 9213 interface. The temperature data recorded is 400 data/second. The results obtained without exposure to the magnetic field, the lowest peak temperature of 577.1998 °C at E40 and the highest peak temperature of 582.1786 °C at E0. The higher the bioethanol content, the lower the temperature of fuel combustion to the low bioethanol viscosity. The increasing magnetic field strength will increase the combustion temperature; hence the fuel burned quickly and the combustion process is more perfect. The result obtained with the magnetic field exposure, the lowest peak temperature of 577.8347 °C is at E40. The highest peak temperature of 587.36 °C is at E0. The use of a magnetic field in the bioethanol fuel mixture can increase the combustion temperature so that the fuel molecules move freely and the fuel is more easily mixed with oxygen. As more fuel is burned, the combustion of the fuel becomes complete

APA, Harvard, Vancouver, ISO, and other styles

15

Salhi, Merouane, Toufik Zebbiche, and Abderrahmane Mehalem. "Stagnation pressure effect on the supersonic flow parameters with application for air in nozzles." Aeronautical Journal 120, no. 1224 (February 2016): 313–54. http://dx.doi.org/10.1017/aer.2015.13.

Full text

Abstract:

ABSTRACTWhen the stagnation pressure of a perfect gas increases, the specific heat and their ratio do not remain constant anymore and start to vary with this pressure. The gas doesn't stay perfect. Its state equation changes and it becomes a real gas. In this case, the effects of molecular size and intermolecular attraction forces intervene to correct the state equation. The aim of this work is to determine the effect of stagnation pressure on the thermodynamic, physical and geometrical supersonic flow parameters in order to find a general form for real gas. With the assumptions that Berthelot's state equation accounts for molecular size and intermolecular force effects, expressions are developed for analysing the supersonic flow for thermally and calorically imperfect gas lower than the dissociation molecules threshold. The design parameters of the supersonic nozzle-like thrust coefficient depend directly on the stagnation parameters of the combustion chamber. The application made for air. A computation of error was made in this case to give a limit of the perfect gas model compared to the real gas model.

APA, Harvard, Vancouver, ISO, and other styles

16

Salhi, Merouane, Toufik Zebbiche, and Abderrahmane Mehalem. "Stagnation pressure effect on Prandtl Meyer function for air." Proceedings of the Institution of Mechanical Engineers, Part G: Journal of Aerospace Engineering 231, no. 2 (August 6, 2016): 326–37. http://dx.doi.org/10.1177/0954410016636913.

Full text

Abstract:

When the stagnation pressure of a perfect gas increases, the specific heat and their ratio do not remain constant anymore and start to vary with this pressure. The gas does not stay perfect. Its state equation change and it becomes for a real gas. In this case, the effects of molecular size and intermolecular attraction forces intervene to correct the state equation, the thermodynamic parameters and the value of Prandtl Meyer function. The aim of this work is developing a new form of Prandtl Meyer function based on those assumptions; and determining the effect of stagnation pressure on this function. With the assumptions that Berthelot’s state equation accounts for molecular size and intermolecular force effects, expressions are developed for analysing the supersonic flow for thermally and calorically imperfect gas lower than the dissociation molecules threshold. The supersonic parameters depend directly on the stagnation parameters of the combustion chamber. The application is for air. A computation of error was made in this case to give a limit of the perfect gas and the high temperature models compared to the real gas model.

APA, Harvard, Vancouver, ISO, and other styles

17

Polifke, W., P. Flohr, and M. Brandt. "Modeling of Inhomogeneously Premixed Combustion With an Extended TFC Model." Journal of Engineering for Gas Turbines and Power 124, no. 1 (February 1, 2000): 58–65. http://dx.doi.org/10.1115/1.1394964.

Full text

Abstract:

In many practical applications, so-called premixed burners do not achieve perfect premixing of fuel and air. Instead, fuel injection pressure is limited, the permissible burner pressure drop is small and mixing lengths are curtailed to reduce the danger of flashback. Furthermore, internal or external piloting is frequently employed to improve combustion stability, while part-load operation often requires burner staging, where neighboring burners operate with unequal fuel/air equivalence ratios. In this report, an extension of the turbulent flame speed closure (TFC) model for highly turbulent premixed combustion is presented, which allows application of the model to the case of inhomogeneously premixed combustion. The extension is quite straightforward, i.e., the dependence of model parameters on mixture fraction is accounted for by providing appropriate lookup tables or functional relationships to the model. The model parameters determined in this way are adiabatic flame temperature, laminar flame speed and critical gradient. The model has been validated against a test case from the open literature and applied to an externally piloted industrial gas turbine burner with good success.

APA, Harvard, Vancouver, ISO, and other styles

18

Guha, A. "Effects of internal combustion and non-perfect gas properties on the optimum performance of gas turbines." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 217, no. 9 (September 1, 2003): 1085–99. http://dx.doi.org/10.1243/095440603322407317.

Full text

Abstract:

With the help of a purpose-built computer program the separate and combined effects of the various aspects of internal combustion and non-perfect gas properties on the optimum performance of gas turbines are examined. The effects of variation of specific heat, addition of fuel mass, pressure losses and dissociation are elucidated. The numerical results have been extensively compared with closed-form analytical solutions and a linear perturbation analysis. The accuracy of a standard, approximate method for predicting gas turbine performance is assessed and its various limitations are identified. The newly established concept of optimum turbine entry temperature is further explored.

APA, Harvard, Vancouver, ISO, and other styles

19

Qin, Wu, Laixing Luo, Anwen Feng, Xianbin Xiao, and Changqing Dong. "Ammonia deep chemical looping combustion on perfect and reduced Fe 2 O 3 : A theoretical account." International Journal of Energy Research 45, no. 7 (February 24, 2021): 10562–71. http://dx.doi.org/10.1002/er.6544.

Full text

APA, Harvard, Vancouver, ISO, and other styles

20

Peng, Song Ji, Yan Ji Hong, Guang Yu Wang, and Hu Pan. "A Measurement Based on Tunable Diode Laser Absorption Spectroscopy for Pressure in Gas Flow." Advanced Materials Research 1051 (October 2014): 910–14. http://dx.doi.org/10.4028/www.scientific.net/amr.1051.910.

Full text

Abstract:

Pressure is a very important parameter for combustion diagnostics since pressure is a good indicator of combustion efficiency .As combustion technologies mature, more accurate and less response time pressure diagnosis are needed. Line of sight (LOS) tunable diode laser absorption spectroscopy (TDLAS) provides a fast, nonintrusive, sensitive and reliable solution for quantitative sensing of multiple flow field parameters including gas temperature, components concentration, and mass flux. So far, there is no mature method to measure gas pressure using TDLAS, and it is very important to perfect TDLAS measuring system with the gain of pressure.This paper intends to found a method based on TDLAS for gas pressure measurement. At first, a gas pressure measuring method is presented. Then, an experiment is conducted in a heated static cell to verify this method. A Direct-Absorption-Based Senor which scans H2O transitions near 1.4 μm was used, and this made the measuring system compact, low cost, simple to operate and quick to response. The experiment successfully measured the pressure in several pressure points, and the results agreed well with the data measured by pressure sensor, average difference is 3.1%.

APA, Harvard, Vancouver, ISO, and other styles

21

Bondrea, Dana Andreya, Lucian Mihaescu, Gheorghe Lazaroiu, Ionel Pisa, and Gabriel Negreanu. "Researches on the mixture limits of animal fats with liquid hydrocarbons for combustion at industrial level." E3S Web of Conferences 112 (2019): 02001. http://dx.doi.org/10.1051/e3sconf/201911202001.

Full text

Abstract:

The experimental research has highlighted the variety of possibilities of combustion of animal fat from bovine and swine mixed with liquid hydrocarbons. Previous research has established that the upper limit for an efficient combustion was 30 %. For a perfect mixing, the lower temperature limit was set to 40 °C. In the fuel laboratory, at the department TMETF was determined the viscosity of the mixtures for different proportions. The values obtained for various concentrations and preheating temperatures were close to the values for liquid hydrocarbons. The experimental researches have studied the combustion of the mixture using a mechanically spraying burner with constant pressure between 14 and 18 bar. The aspiration of the mixture is done from a specially designed tank; this tank is equipped with an electric heater, in order to maintain the mixture at a constant temperature between 40 °C to 50 °C. After that, the burner heats again the mixture with an integrated heating device up to 75 °C. The burner is also equipped with an air blower, pump and a calibrated nozzle. The combustion resulted from the experimental boiler with a power rated to 55 kW were monitored with a thermal vision camera and an exhaust gas analyser. This research has demonstrated the viability of using this type of mixtures in energetic burning equipment designed for liquid hydrocarbons.

APA, Harvard, Vancouver, ISO, and other styles

22

Guha, A. "Performance and optimization of gas turbines with real gas effects." Proceedings of the Institution of Mechanical Engineers, Part A: Journal of Power and Energy 215, no. 4 (June 1, 2001): 507–12. http://dx.doi.org/10.1243/0957650011538631.

Full text

Abstract:

The influence of various levels of mathematical modelling on gas turbine performance is systematically analysed. It is shown that internal combustion with real gas effects gives rise to an optimum turbine entry temperature which does not arise in a perfect gas analysis and has not been described previously in the literature. At any pressure ratio, the maximum possible efficiency with real gas effects is significantly lower (15-20 per cent) than the maximum possible value predicted by a perfect gas analysis. An explicit equation has been derived for determining the optimum pressure ratio as a function of turbine entry temperature and component efficiencies. It is shown that the optimum design depends very strongly on turbine and compressor efficiencies. It is demonstrated that the optimum relation between pressure ratio and turbine entry temperature depends strongly on whether the optimization is carried out at fixed pressure ratios or at fixed temperatures. All previous references seem to have considered only the latter method.

APA, Harvard, Vancouver, ISO, and other styles

23

Costa, Fernando S., and Gustavo A. A. Fischer. "Propulsion and Thermodynamic Parameters of van der Waals Gases in Rocket Nozzles." International Journal of Aerospace Engineering 2019 (August 14, 2019): 1–11. http://dx.doi.org/10.1155/2019/3139204.

Full text

Abstract:

Propellants or combustion products can reach high pressures and temperatures in advanced or conventional propulsion systems. Variations in flow properties and the effects of real gases along a nozzle can become significant and influence the calculation of propulsion and thermodynamic parameters used in performance analysis and design of rockets. This work derives new analytical solutions for propulsion parameters, considering gases obeying the van der Waals equation of state with specific heats varying with pressure and temperature. Steady isentropic one-dimensional flows through a nozzle are assumed for the determination of specific impulse, characteristic velocity, thrust coefficient, critical flow constant, and exit and throat flow properties of He, H2, N2, H2O, and CO2 gases. Errors of ideal gas solutions for calorically perfect and thermally perfect gases are determined with respect to van der Waals gases, for chamber temperatures varying from 1000 to 4000 K and chamber pressures from 5 to 35 MPa. The effects of covolumes and intermolecular attraction forces on flow and propulsion parameters are analyzed.

APA, Harvard, Vancouver, ISO, and other styles

24

Liu, Jun, Gui Wu Fu, and Zhi Gang Xi. "Research and Development of High Reflection Infrared Radiating Coating Adopted on Ceramic Kilns." Advanced Materials Research 472-475 (February 2012): 363–66. http://dx.doi.org/10.4028/www.scientific.net/amr.472-475.363.

Full text

Abstract:

Make nano-scale Al doped with SiC by combustion synthesis with Si, C and Al powder as the raw materials. This kind of nano-scale Al doped with SiC boasts high infrared radiance, and thus can be used for energy conservation of thermal equipments at 800~1500°C. Details include: adopt the synthetize nano ceramic powder of high emissivity at low expense to compound coatings, and deposit the coating at the inwall of thermal kilns to make perfect combination so as to keep high emission rate for the purpose of saving energy in the subsequent process of actual use.

APA, Harvard, Vancouver, ISO, and other styles

25

Liu, Bao Ling. "A Study on the Mathematic Model of Nox Emission in Coal-Fired Boiler with Opposed Combustion Pattern." Advanced Materials Research 403-408 (November 2011): 8–12. http://dx.doi.org/10.4028/www.scientific.net/amr.403-408.8.

Full text

Abstract:

The perfect mathematic model is critical to reseaech the NOx emission charateristic. In this paper, a new statistical learning algorithm SVM(support vector machine) was used to establish the model, based on the mechanism analysis of the NOx emission characteristics, and grid optimization method was applied to determine the model parameters. The model was tested on a 660MW power plant ,and the result indicated that SVM was a good tool for building NOx emission model and had better generalization ability and higher calculation speed comparing with BP modeling approaches.

APA, Harvard, Vancouver, ISO, and other styles

26

Liu, Gui Yang, Jun Ming Guo, Bao Sen Wang, and Ying He. "Effect of Further Calcination on the Phase Structure of LiMn₂O₄ Prepared by a Solution Combustion Synthesis." Applied Mechanics and Materials 66-68 (July 2011): 768–71. http://dx.doi.org/10.4028/www.scientific.net/amm.66-68.768.

Full text

Abstract:

In this paper, LiMn2O4 materials were prepared by a solution combustion synthesis method using acetate salts as raw materials and acetic acid as fuel. The effect of further calcination at 500°C and 600°C on the phase structure and composition were investigated. The composition and phase structure are determined by X-ray diffraction (XRD). XRD results indicated that the main phase of the products was LiMn2O4,and there was a trace amount Mn2O3 impurity in the products prepared at 500°C and 600°C. The impurity Mn2O3 in the products prepared at 500°C is increased with increasing calcination time, but the Mn2O3 in the products prepared at 600°C is decreased. The grain sizes of the products prepared at 500°C and 600°C are increased with increasing calcination time, and the grain sizes of the products prepared at 600°C are larger than these of the products prepared at 500°C. The lattice parameters of the products prepared at 500°C and 600°C are smaller than that of LiMn2O4 with perfect crystal, and the lattice parameters of the products are more close to that of LiMn2O4 with perfect crystal.

APA, Harvard, Vancouver, ISO, and other styles

27

Ksepko, Ewelina, and Rafal Lysowski. "Stable Mixed Fe-Mn Oxides Supported on ZrO2 Oxygen Carriers for Practical Utilization in CLC Processes." Catalysts 11, no. 9 (August 29, 2021): 1047. http://dx.doi.org/10.3390/catal11091047.

Full text

Abstract:

The objective of the research was to prepare Fe-based materials for use as oxygen carriers (OCs) and investigate their reactivity in terms of their applicability to energy systems. The performance of ZrO2 supported Fe-Mn oxide oxygen carriers with hydrogen/air in an innovative combustion technology known as chemical looping combustion (CLC) was analyzed. The influence of manganese addition (15–30 wt.%) on reactivity and other physical properties of oxygen carriers was discussed. Thermogravimetric analyses (TGA) were conducted to evaluate their performance. Multi-cycle tests were conducted in TGA with oxygen carriers utilizing gaseous fuel. The effect of redox cycle number and temperature on stability and oxygen transport capacity and redox reaction rate were also evaluated. Physical-chemical analysis such as phase composition was investigated by XRD, while morphology by SEM-EDS and surface area analyses were investigated by the BET method. For screening purposes, the reduction and oxidation were carried out from 800 °C to 1000 °C. Three-cycle TGA tests at the selected temperature range indicated that all novel oxygen carriers exhibited stable chemical looping combustion performance, apart from the reference material, i.e., Fe/Zr oxide. A stable reactivity of bimetallic OCs, together with complete H2 combustion without signs of FeMn/Zr oxide agglomeration, were proved. Oxidation reaction was significantly faster than the reduction reaction for all oxygen carriers. Furthermore, the obtained data indicated that the materials have a low cost of production, with superior reactivity towards hydrogen and air, making them perfect matching carriers for industrial applications for power generation.

APA, Harvard, Vancouver, ISO, and other styles

28

Feng, Jun Xiao, Qi Bo Cheng, and Si Jing Yu. "Numerical Simulation on Process of Flow and Heat Transfer in Upright Magnesium Reducing Furnace." Advanced Materials Research 383-390 (November 2011): 6657–62. http://dx.doi.org/10.4028/www.scientific.net/amr.383-390.6657.

Full text

Abstract:

Based on the analysis of structural characteristic superiority, the process of combustion, flue gas flow and heat transfer in the upright magnesium reducing furnace, the three dimensional mathematical model is devoloped. And numerical simulation is performed further with the commercial software FLUENT. Finally, the flow and temperature field in furnace and temperature field in reducing pot have been obtained. The results indicate that the upright magnesium reducing furnace has perfect flue gas flow field and temperature field to meet the challenge of the magnesium reducing process; the major factors that affect the magnesium reducing reaction are the low thermal conductivity of slag and the high chemical reaction heat absorption.

APA, Harvard, Vancouver, ISO, and other styles

29

Yuan, Yan Kun, Gang Xue, Sai Fei Wang, and Xue Liang Zhang. "Preparation and Characterization of Rare Earth Composite Catalytic Materials for Conversion of Exhaust from Natural Gas Automobiles." Applied Mechanics and Materials 320 (May 2013): 413–18. http://dx.doi.org/10.4028/www.scientific.net/amm.320.413.

Full text

Abstract:

A series of rare-earth composite catalytic material LZ1,LZ2 and LZ3 that contains mixture of La0.9Sr0.1Co0.5Mn0.5O3and Ce0.7Zr0.3O2in different proportion (3:7, 5:5, 7:3) were prepared by a sol-gel method and characterized by X-ray diffraction (XRD), specific surface analysis (BET) , Transmission electron microscopy (TEM) and temperature programmed reduction (TPR). The results indicated that in LZ3, a perfect crystal structure of perovskite and a cubic fluorite structure were formed. Besides LZ3 presented scattered spherical granules with a particle size of about 30 nm and a specific surface area of 20.9870 m2/g. The temperature of reduction peak was lowest (490°C) and peak area was larger, so it had the best catalytic activity for methane combustion.

APA, Harvard, Vancouver, ISO, and other styles

30

Zhang, Rui Zhu, Jie Yang, Da Kao Yan, Zhi Meng Guo, and Wan Shan Su. "Consolidation of High-Level Radioactive Wastes into Strontium Titanate by CS Method." Materials Science Forum 704-705 (December 2011): 625–30. http://dx.doi.org/10.4028/www.scientific.net/msf.704-705.625.

Full text

Abstract:

Strontium Titanate synroc samples were synthesized by combustion cynthesis (CS). Sr directly took part in the synthesis process. As a result, loading content issue is basically resolved. The products were characterized by density, microhardness X-ray diffraction, and scanning electron microscopy (SEM/EDS). The leaching rate was measured by the method of PCT. The results indicate that the Sr2+-SrTiO3 compound with high density, low leach rate and high property stability and the synthesis process is feasible in technology and economy. It can be concluded that the Strontium Titanate synroc is a perfect material to immobilize HLW Keywords: Strontium Titanate, high-level radioactive waste (HLW), immobilization, self –propagating high –temperatures synthesis (SHS).

APA, Harvard, Vancouver, ISO, and other styles

31

Liu, Hong, Fan Peng, and Yi Liu. "Final Machining of Large-Scale Engine Block with Modularized Fixture and Virtual Manufacturing Technologies." Journal of Engineering 2017 (2017): 1–6. http://dx.doi.org/10.1155/2017/3648954.

Full text

Abstract:

This paper addresses the issue of unstable machining quality of large-scale high-precision internal combustion engine block; the key machining technologies of complex thin-wall internal combustion engine block are studied. This dissertation takes the L type engine block that is used as research object; the modular and fast changing fixtures have been designed for machining engine blocks; due to the fact that this kind of engine blocks has different number of cylinders, we establish a model of precision machining scheme based on virtual manufacturing technology and manufacturing method; on this basis, the scheme is applied to the actual production process to verify the feasibility of the program. The research shows that the precision machining scheme established based on virtual manufacturing technology can effectively solve the key machining technology of the engine block, and one purpose of using this method is to improve machining precision and efficiency of the assembly production. This study intends to propose final machining technology project of high-precision products, and this will formulate and gradually perfect a machining process framework for large engine block, which has engineering exploration value to promote machining technology.

APA, Harvard, Vancouver, ISO, and other styles

32

Wang, Zhong Jie, Ning Han, and Jia Wang. "The Study on the Fuzzy Control Algorithm for Main Steam Pressure Control of Circulated Fluidized Bed Boiler." Advanced Materials Research 383-390 (November 2011): 2092–96. http://dx.doi.org/10.4028/www.scientific.net/amr.383-390.2092.

Full text

Abstract:

The main steam Pressure is one of the most important guidelines on Circulating Fluidized Bed Boiler (CFBB) operation quality and an important part in control system of CFBB. However, It is very difficult to establish the exact mathematical models of controlled objects because the combustion system of circulating fluidized bed boiler is an object that has many features: distributed parameters, nonlinear, time-varying and long time-delaying. it is unfavorable to control it with traditional controller. Therefore , In this paper fuzzy controller is used in controlling main vapor pressure systems of CFBB, and the fuzzy cascade control system is designed. In computer simulation, the fuzzy cascade control system exert stably, and has perfect control effect to main vapor pressure systems of CFBB.

APA, Harvard, Vancouver, ISO, and other styles

33

Rifal, Mohamad, and Wawan Rauf. "Analisis Penggunaan Bahan Bakar Etanol-Pertalite Pada Motor Honda Scoopy 110 cc." Gorontalo Journal of Infrastructure and Science Engineering 1, no. 1 (April 1, 2018): 55. http://dx.doi.org/10.32662/gojise.v1i1.141.

Full text

Abstract:

The production of the crude oil in Indonesia is slowly deceasing by the year, while the consumption of the fuel is still increasing. The matter being comparable within its consumtion is that it makes Indonesia keep impoerting the fuel in order to fulfill its need in every year. It is because there is no new invention of the new oil-mill. Thus, a new penetration to provide an alternative fuel to press the consumption level is needed. Ethanol however, is one of the newest alternative fuels which can be used as the additional substance of the use of the fossil fuel. Ethanol contains of up to 35% oxygen so that it will produce the perfect combustion even if it is in small unit of substance. The aim of this research was to find out the effect of the use of the mixture of the ethanol-pertalite toward the fuel combustion. The research was using the Honda Scoopy 110 cc motorcycle with 1 cylinder injection system. The liquid tank is designed by using plastic container so that it will be possible to be detached and paired to make the consumtion measuring easier. The test vehicle was operated above chasis dynamometer. Engine scanner, especially for Honda was used to sett the rpm, finding out the throotle position, ignition timing, oxygen sensor and the ratio of water fuel. The result of the research was showing that the use of the mixture fuel E-40 is the best mixture, in which E-40 usage is 14,3% more frugal rather that the combustion of the pure pertalite.

APA, Harvard, Vancouver, ISO, and other styles

34

Lamas, D. G., R. O. Fuentes, I. O. Fábregas, M. E. Fernández de Rapp, G. E. Lascalea, J. R. Casanova, N. E. Walsöe de Reca, and A. F. Craievich. "Synchrotron X-ray diffraction study of the tetragonal–cubic phase boundary of nanocrystalline ZrO2–CeO2synthesized by a gel-combustion process." Journal of Applied Crystallography 38, no. 6 (November 12, 2005): 867–73. http://dx.doi.org/10.1107/s0021889805025343.

Full text

Abstract:

The crystal structures of a number of nanocrystalline ZrO2–CeO2solid solutions, synthesized by a pH-controlled nitrate-glycine gel-combustion process, were studied. By using a synchrotron X-ray diffractometer, small peaks of the tetragonal phase, which correspond to forbidden reflections in the case of a perfect cubic fluorite structure, were clearly detected. By monitoring the most intense of these reflections, 112, as a function of the CeO2content, the tetragonal–cubic phase boundary was found to be at 85 (5) mol% CeO2. For a CeO2content up to 68 mol%, a tetragonal phase withc/a> 1 (known as thet′ form) was detected, whereas, between 68 and 85 mol% CeO2, the existence of a tetragonal phase withc/a= 1 and oxygen anions displaced from their ideal positions in the cubic phase (thet′′ form) was verified. Finally, solid solutions with higher CeO2contents exhibit the cubic fluorite-type phase.

APA, Harvard, Vancouver, ISO, and other styles

35

Listiyono, Listiyono Yono, Bambang Irawan, and Agus Hardjito. "OPTIMALISASI COMPOSIT ABSORBER PADA MUFFLER UNTUK MENURUNKAN KADAR EMISI GAS BUANG MOTOR BENSIN." Jurnal Energi dan Teknologi Manufaktur (JETM) 2, no. 01 (June 30, 2019): 13–22. http://dx.doi.org/10.33795/jetm.v2i01.33.

Full text

Abstract:

The problem of air pollution caused by burning of fossil fuels and the process of combustion is increase. Many efforts. has done to reduce the air pollution problem. Starting from the combustion process to give equipment as reduce gass emissions and raise the quality of burning, but the ari pollution is still high, especially the burning gasoline of motor fuel Air pollution a motor vehicle exhaust gases come from the rest of the results of the combustion of fuel that do not be unraveled or burning with perfect. Bad gass emissions caused by incomplete combustion of fuel in the fuel chamber. Element contained in the exhaust gasses are CO, NO2, HC, C, H2, CO2, H2O dan N2, The CO and CO2 gasses is the most radical among the others. The CO gass is poisonous, if a men inhale this gas can caused death. While the CO2 gass is a radical gass who can cause the greenhouse effect. The aims of this research are : 1 to understand the effect of carbon composite material, lime and glue towards reductions in emission of motor vehicle . 2. to find out the optimal composition of composite material to reducing the emission level of motor vehicle.The study and research in order to reduce gas emissions until now have done using installation catalyst on muffler. In this research, the mixed of absorption exhaust gas is observed. Especially the poisonous gas. The mixture material is made from carbon, lime and glue. And then installed on muffler filter. A mixture is made by comparation varied. Using minitab software for analyse and the conclusions are: 1. The addition of absorben composition between carbon (C) with lime (CaO) on exhaust can reduce the level of gass emission. 2. The most optimal composition absorben C and CaO in absorption and produce the lowest C and CO2 gass is C and CaO with comparison ratio is 30 %: 70 %

APA, Harvard, Vancouver, ISO, and other styles

36

Valíček, Jan, Jana Müllerová, Vlastimil Kuběna, Pavel Koštial, Marta Harničárová, and Marian Mikulík. "Emission Distribution and Regulation of Local Heat Source." Defect and Diffusion Forum 326-328 (April 2012): 330–34. http://dx.doi.org/10.4028/www.scientific.net/ddf.326-328.330.

Full text

Abstract:

Pollutants can be classified according to their chemical composition, harmfulness, hazardousness, risk rate and toxicity. The most monitored pollutants are particulate matter (PM), carbon monoxide (CO), nitrogen oxide (NOx), sulfur dioxide (SO2), organic substances which are in the form of gaseous phase in waste gases expressed as total organic carbon, dibenzodioxins and dibenzofurans [1-3]. Other pollutants are divided into several groups and subgroups, such as substances with carcinogenic effects (asbestos, Co, Cd, Be, Ni, As, Cr, dioxins, etc.), solid inorganic contaminants (He, Se, animony, and others) and inorganic pollutants in the form of gases (HCl, HF, ammonia, etc.), organic gases and vapours (phenol, toluene, acetone and many others) and gases causing the greenhouse effect (CO2, methane, N2O, hydrofluorocarbons, etc.). The term particulate matter, or suspended matter refers to the emissions of a wide range of wind drift solids and liquid particles of material in size from several nanometres up to 0.5 mm, which stay in the air for some time. This is a major component of atmospheric pollution, which contributes to harmful effects not only on human health but also on intensity of materials degradation. Into the atmosphere, where we can meet them, regardless of particle size and chemical composition, in the form of a complex heterogeneous mixture, they are released from burning fossil fuels and also from burning biomass-based fuels, while domestic heating accounts for about 16% of the total production of particulate matter [4,5,6]. This percentage represents a degree of imperfect combustion of fuels used in local heating. Emissions from incomplete combustion are undesirable from the point of view of human health as well as from the economic point of view, because this leads to the degradation of materials. Nevertheless, since fuel combustion is necessary for the society, emissions are still produced. This paper presents an automated method of perfect combustion control in local heating in order to minimize emissions being produced.

APA, Harvard, Vancouver, ISO, and other styles

37

Yuniarto Agus Winoko, Santoso, and Khambali. "PENGARUH SUHU BAHAN BAKAR TERHADAP EMISI GAS BUANG PADA MESIN BENSIN 1800 cc." Jurnal Teknik Ilmu Dan Aplikasi 9, no. 2 (April 28, 2021): 4–7. http://dx.doi.org/10.33795/jtia.v9i2.24.

Full text

Abstract:

The perfect combustion process can occur if the high compression pressure, proper ignition time, and suitable fuel air mixture. Suitable fuel air mixture can be obtained by heating the fuel to reduce its viscosity so the mixture is more homogeneous. Fuel heating can be done in various ways, such as by utilizing the heat of radiator water coming out of the engine. The purpose of the study is determine effect of the fuel heating to exhaust emission of gasoline engine 1800cc. The study uses experimental with the variable used pertamax with temperature 40°, 50°, 60°, and 70°. The dependent variable in the study is exhaust emission of gasoline engine. The results of the study indicate that fuel heating affects exhaust emissions. Temperature that affects the exhaust gas emissions at 60o C with the use of pertamax fuel.

APA, Harvard, Vancouver, ISO, and other styles

38

Witono, Kris, and Akhsanu Takwim. "Pengaruh Variasi Lip Thickness Pada Nozzle Terpancung Dengan Swirl Terhadap Kestabilan Api Difusi Concentric Jet Flow." Jurnal Energi dan Teknologi Manufaktur (JETM) 1, no. 01 (June 29, 2018): 11–15. http://dx.doi.org/10.33795/jetm.v1i01.10.

Full text

Abstract:

One of the factors that affect flame diffusion characteristics is the geometry of fuel nozzles in the installation of the combustion system. The nozzle shape greatly affects the turbulence that occurs between fuel and air. This process causes the formation of flow recirculation zones. This process thus produces homogeneous mixing and obtains near perfect combustion. The recirculation zones are zones arising from breaking the flow rate. So as to cause a vortex and backflow around the tip of the nozzle. It is this feedback which inhibits and simultaneously suppresses the flame so that the flow rate of the fuel mixture and the air is maintained lower or equal to the flame velocity. In this study, lip thickness variations in nozzles were used with swirls with variations of 0, 4, 8, 12, and 16 mm to determine flame stability of concentric jet flow diffusion. Fuel velocity and air are varied to obtain flame stability data. In addition, to support and reinforce the results obtained from this study, direct photograph and shadowgraph methods are used to obtain flow pattern visualization. The result of the research shows that the stability of flame concentric jet flow diffusion has increased along with the decreasing of lip thickness in nozzle. The largest flame stability area is obtained in 4 mm thick lip thickness.

APA, Harvard, Vancouver, ISO, and other styles

39

Xiao, Xianbin, Wu Qin, Jianye Wang, Junhao Li, and Changqing Dong. "Effect of surface Fe-S hybrid structure on the activity of the perfect and reduced α-Fe2O3(001) for chemical looping combustion." Applied Surface Science 440 (May 2018): 29–34. http://dx.doi.org/10.1016/j.apsusc.2017.12.252.

Full text

APA, Harvard, Vancouver, ISO, and other styles

40

Suliono, Suliono, Felix Dionisius, and Bambang Sudarmanta. "PENGARUH KECEPATAN ALIRAN UDARA DENGAN PENGATURAN DIMMER PADA TEKANAN UDARA MASUK PADA PROSES GASIFIKASI SEKAM PADI TERHADAP PEMBENTUKAN FLAMABLE GAS." JTT (Jurnal Teknologi Terapan) 6, no. 1 (April 15, 2020): 62. http://dx.doi.org/10.31884/jtt.v6i1.237.

Full text

Abstract:

The biomass gasification process is a way to obtain combustible syn-gas through combustion of biomass in a closed reactor with the help of air from a compressed blower. Without the help of air gas formation process is not possible, the combustion in the furnace must have air that can start a fire. The tool for supplying air is a pressure blower. The purpose of this study was to obtain a stoichiometric air and biomass mixture in the rice husk gasification process. With the stoichiometric air fuel ratio (AFR) in the rice husk gasification process, it will produce a perfect flammable syn-gas.The method used in this research is to change the rice husk solid through the gasification process. The gas released in the gasification process will be varied at the blower speed with or without using a dimmer. From the test results, it can be seen in the syn-gas output from the reactor. on dimmer 1 the inlet airspeed is 3.5 m / s, on dimmer 2 the airspeed is 4.0 m / s. In dimmer 3 the air velocity is 4.5 m / s and in dimmer 4 the air velocity produced is 5.0 m / s From the results of testing the air velocity of each variation that enters the reactor only air velocity 4.5 m / s and 5.0 m / s or in dimmers 3 and 4 which can produce flammable syn-gas.

APA, Harvard, Vancouver, ISO, and other styles

41

Mahmoud, Kamel G., Oliver Knaus, Tigran Parikyan, Guenter Offner, and Stjepan Sklepic. "An integrated model for the performance of piston ring pack in internal combustion engines." Proceedings of the Institution of Mechanical Engineers, Part K: Journal of Multi-body Dynamics 232, no. 3 (October 25, 2017): 371–84. http://dx.doi.org/10.1177/1464419317736676.

Full text

Abstract:

Piston rings are important components in internal combustion engines. Their primary function is to seal dynamically the gap between moving piston and cylinder liner surface in order to prevent the combustion gases from penetrating into the crankcase. The rings also control the oil leakage from the crankcase to the combustion chamber. The performance of the piston ring pack impacts the engine efficiency, durability and emissions. The recognition of the impact of the ring-pack performance on the engine design resulted in a sustained effort of research and development aimed at understanding the operation of the piston ring pack. Most of the published models developed in this field are two-dimensional assuming that the ring and liner are perfect circles for the purpose of modelling the axial and radial dynamics. Although this approach has proved to be useful, there exist a number of asymmetrical characteristics of the power cylinder system that can be crucial to the ring-pack performance and therefore it is considered to be appropriate. In this work, an integrated methodology that handles the complex ring-pack mechanism is presented. The physics of the ring-pack mechanism covers the three-dimensional piston ring dynamics of asymmetric engine cylinder due to bore distortion, the mixed lubrication at ring running face as well as the ring flanks and the interring gas dynamics. The modelling method is verified in two steps. In the first step, the dynamic behaviour of the three-dimensional ring model is verified against a commercial finite element software by comparing the eigenmodes up to a frequency of about 1 kHz. In the second step, the ring-pack modelling approach using three-dimensional ring models is also verified against a commercial ring dynamics program, which is based on the two-dimensional modelling. It is shown that the three-dimensional ring dynamics modelling method has advantages over the two-dimensional modelling approach as it facilitates studying the influence of the non-uniform twist along its circumference (ring winding), the effect of bore distortion on blow-by, ring friction, friction power losses and wear.

APA, Harvard, Vancouver, ISO, and other styles

42

Cardone, Massimo, Renato Marialto, Roberto Ianniello, Maurizio Lazzaro, and Gabriele Di Blasio. "Spray Analysis and Combustion Assessment of Diesel-LPG Fuel Blends in Compression Ignition Engine." Fuels 2, no. 1 (December 31, 2020): 1–15. http://dx.doi.org/10.3390/fuels2010001.

Full text

Abstract:

A major challenge for internal combustion engines (ICEs), and diesel engines, in particular, is the reduction of exhaust emissions, essentially nitrogen oxides (NOx) and particulate matter (PM). In this regard, the potential of LPG-diesel blends was evaluated in this work. The LPG and diesel blends were externally prepared by exploiting their perfect miscibility at high pressures. Two diesel-LPG mixtures with 20% and 35% by mass LPG concentrations were tested. In terms of spatial and temporal evolution, the spray characterization was performed for the two blends and pure diesel fuel through high-speed imaging technique. The combustion behavior, engine performance and exhaust emissions of LPG-diesel blends were evaluated through a test campaign carried out on a single-cylinder diesel engine. Diesel/LPG sprays penetrate less than pure diesel. This behavior results from a lower momentum, surface tension and viscosity, of the blend jets in comparison to diesel which guarantee greater atomization. The addition of LPG to diesel tends to proportionally increase the spray cone angle, due to the stronger turbulent flow interaction caused by, the lower density and low flash-boiling point. Because of improved atomization and mixing during the injection phase, the blends have shown great potential in reducing PM emissions, without affecting engine performance (CO2 emissions). The addition of LPG resulted in a significant smoke reduction (about 95%) with similar NOx emissions and acceptable THC and CO emissions. Furthermore, the low cetane number (CN) and high low-heating value (LHV) ensuring leaner air-fuel mixture, and improvements in terms of efficiency, particularly for a blend with a higher concentration of LPG.

APA, Harvard, Vancouver, ISO, and other styles

43

Liu, Xiao Ting, Bao Dong Wang, Yong Feng Xiao, Xiao Huan Wang, Li Jun Zhao, Geng Zhi Yu, and Qi Sun. "Alumina Extraction from Alumina Rich Fly Ash Generated from Inner-Mongolia Chinese Coal." Advanced Materials Research 1065-1069 (December 2014): 1725–31. http://dx.doi.org/10.4028/www.scientific.net/amr.1065-1069.1725.

Full text

Abstract:

Generated during the combustion of coal for electricity production, fly ash is a solid waste and causes great ecomomic burden and serious environmental pollution. On the other hand, it is a good resource for the preparation of industrial products. Especially, alumina rich fly ash from Inner-Mongolia Guohua Junggar Power Plant typically contains 45-55% alumina, 30-40% silica, and 5-10% other metallic oxides, it is a perfect resource for alumina extraction. In order to improve the utilization value of alumina rich fly ash and lessen environmental strain, a novel approach for alumina extraction from alumina rich fly ash was proposed. The proposed process includes a pre-desilication process, soda lime sintering process, dissolving process, carbonation process and calcination process. The technological conditions for alumina extraction from Junggar alumina rich fly ash were optimized by means of orthogonal experment design. The extraction rate of alumina was 96%. Value-added products, such as electrolytic grade alumina and white carbon black, were produced at the same time.

APA, Harvard, Vancouver, ISO, and other styles

44

Roy, Badal Dev, and R. Saravanan. "Experimental Evaluation of Turbo-Matching Appropriateness of B60J67, B60J68, A58N70 and A58N72 Turbo-Chargers for a Commercial Vehicle Engine." International Journal of Emerging Research in Management and Technology 6, no. 11 (June 13, 2018): 71. http://dx.doi.org/10.23956/ijermt.v6i11.49.

Full text

Abstract:

The Turbocharger is a charge booster for internal combustion engines to ensure best engine performance at all speeds and road conditions especially at the higher load. Random selection of turbocharger may lead to negative effects like surge and choke in the breathing of the engine. Appropriate selection or match of the turbocharger (Turbomatching) is a tedious task and expensive. But perfect match gives many distinguished advantages and it is a one time task per the engine kind. This study focuses to match the turbocharger to desired engine by simulation and on road test. The objective of work is to find the appropriateness of matching of turbochargers with trim 67 (B60J67), trim 68 (B60J68), trim 70 (A58N70) and trim 72 (A58N72) for the TATA 497 TCIC -BS III engine. In the road-test (data-logger method) the road routes like highway and slope up were considered for evaluation. The operating conditions with respect various speeds, routes and simulated outputs were compared with the help of compressor map.

APA, Harvard, Vancouver, ISO, and other styles

45

Yousaf, Muhammad, Hafiz Muhammad Rafique, Muhammad Amin, Shahid Mahmood Ramay, and Shahid Atiq. "Enhanced ferromagnetic characteristics in Mn-doped ZnO: A promising diluted magnetic semiconductor." Modern Physics Letters B 30, no. 32n33 (November 30, 2016): 1650398. http://dx.doi.org/10.1142/s021798491650398x.

Full text

Abstract:

Zn[Formula: see text]Mn[Formula: see text]O ([Formula: see text] = 0, 0.02, 0.04, 0.06, 0.08 and 0.1) nanocrystalline diluted magnetic semiconductors (DMSs) were synthesized using sol–gel-based auto-combustion technique. X-ray diffraction (XRD) analysis of all the synthesized samples indicated pure wurtzite hexagonal structure without any secondary phase with perfect solubility of Mn contents in ZnO matrix. The increase in Mn concentration reduced the average crystallite size as evaluated by the Scherrer’s formula. Morphological analysis performed using a field emission scanning electron microscope (FESEM) indicated nearly an ordered surface morphology with some porosity and few cracks. Energy dispersive X-ray (EDX) spectroscopy confirmed the stoichiometric contents of Zn, Mn and O in each sample. Micrographs of all the samples exhibited a decrease in grain size with increase of Mn contents. Magnetic measurements performed using vibrating sample magnetometer (VSM) confirmed room temperature ferromagnetism exhibiting an increase in saturation magnetization and coercivity with increasing Mn contents in all the prepared samples.

APA, Harvard, Vancouver, ISO, and other styles

46

Alshwawra, Ahmad, Florian Pohlmann-Tasche, Frederik Stelljes, and Friedrich Dinkelacker. "Enhancing the Geometrical Performance Using Initially Conical Cylinder Liner in Internal Combustion Engines—A Numerical Study." Applied Sciences 10, no. 11 (May 27, 2020): 3705. http://dx.doi.org/10.3390/app10113705.

Full text

Abstract:

Reducing friction is an important aspect to increase the efficiency of internal combustion engines (ICE). The majority of frictional losses in engines are related to both the piston skirt and piston ring–cylinder liner (PRCL) arrangement. We studied the enhancement of the conformation of the PRCL arrangement based on the assumption that a suitable conical liner in its cold state may deform into a liner with nearly straight parallel walls in the fired state due to the impact of mechanical and thermal stresses. Combining the initially conical shape with a noncircular cross section will bring the liner even closer to the perfect cylindrical shape in the fired state. Hence, a significant friction reduction can be expected. For the investigation, the numerical method was first developed to simulate the liner deformation with advanced finite element methods. This was validated with given experimental data of the deformation for a gasoline engine in its fired state. In the next step, initially conically and/or elliptically shaped liners were investigated for their deformation between the cold and fired state. It was found that, for liners being both conical and elliptical in their cold state, a significant increase of straightness, parallelism, and roundness was reached in the fired state. The combined elliptical-conical liner led to a reduced straightness error by more than 50% compared to the cylindrical liner. The parallelism error was reduced by 60% to 70% and the roundness error was reduced between 70% and 80% at different liner positions. These numerical results show interesting potential for the friction reduction in the piston-liner arrangement within internal combustion engines.

APA, Harvard, Vancouver, ISO, and other styles

47

Zhang, Qian, Jun Yan, Tian Peng Li, and Jing Wang. "Preparation of Magnetic Expanded Graphite by Sol-Gel Method and its Electromagnetic Properties." Advanced Materials Research 295-297 (July 2011): 93–97. http://dx.doi.org/10.4028/www.scientific.net/amr.295-297.93.

Full text

Abstract:

In order to transform the diamagnetism of expanded graphite (EG) to ferrimagnetism and improve its electromagnetic interferential capability, nano γ-Fe2O3/EG magnetic composite materials was prepared by sol-gel and low temperature self-combustion technique. The as prepared samples were characterized by SEM, XRD and Magnetic hysteresis cycle test. The results indicated that the composite materials had ferrimagnetism property after the embedding of γ-Fe2O3, but the average conductivity of the composites decreases gradually with the increase of γ-Fe2O3. Different mixing ratio of ferrite gel and graphite intercalation compounds produced ferric oxide with different crystal form and shape. When the content of ferrite sol was low, spherical γ-Fe2O3with the mean size of 31.69nm was formed, and spread unevenly on the surface and interformational micelles of EG. High content of ferrite sol (83wt%) produced more perfect crystal γ-Fe2O3of pentahedron shape with the mean size of 44.68nm, and a few of α-Fe2O3occurred which lead to the decline of the magnetic property of the composite materials.

APA, Harvard, Vancouver, ISO, and other styles

48

Chan, S. H., X. S. Chen, and C. Arcoumanis. "Measurement and Signal Reconstruction of Transient Nitric Oxide Emissions in the Exhaust of a Turbocharged Diesel Engine." Journal of Dynamic Systems, Measurement, and Control 119, no. 4 (December 1, 1997): 620–30. http://dx.doi.org/10.1115/1.2802370.

Full text

Abstract:

A well-developed technique, based upon a combined experimental and phenomenological modeling approach, has been adopted for the measurement of nitric oxide (NO) emissions in a diesel engine exhaust under transient engine operation. The dynamic behavior of the chemiluminescent analyzer used for the measurement of NO emissions is characterized by a single gas diffusion model followed by three perfect gas-mixing models. The response of the analyzer is obtained using a computer-controlled transient NO emission simulator, which randomly generates a square-pulse train of NO gas and concurrently measures its signal output. Signal prediction and reconstruction analysis were performed, which has demonstrated the predictive and reconstructive capabilities of the phenomenological analyzer model. On-line nitric oxide emission measurements were obtained in a computer-controlled dynamic engine test bed having three different control modes and fuel injection timing settings. The results have shown that the transient nitric oxide concentration is very sensitive to the engine operating condition prior to the transients as well to the amount of fuel injected into the combustion chamber at the start of the transient operation.

APA, Harvard, Vancouver, ISO, and other styles

49

YING, GUOBING, and XIANG WANG. "NUMERICAL SIMULATION OF THE SHS TEMPERATURE FIELDS OF Al-Ti-C SYSTEM BASED ON PLANE PROPAGATING PATTERN." International Journal of Modern Physics C 20, no. 07 (July 2009): 1087–92. http://dx.doi.org/10.1142/s0129183109014229.

Full text

Abstract:

Three-dimensional heat equations of Al - Ti - C system at the perfect state of self-propagating high-temperature synthesis (SHS) have been established according to the temperature distribution in the reactants, which may be disturbed by density, heat capacity, porosity, conductivity and radiance. Then the effective thermal conductivity and boundary conditions have been revised according to the practical condition. The heat equation of plane propagating pattern has been derived based on the assumption that the propagating pattern at the combustion front was plane pattern. Finally, the temperature distribution of different parts in the 50 Al -40 Ti -10% C (wt.%) preformed specimen was simulated by means of finite element method. Simulation results show that the central temperature of each cross-section is higher than that of other parts. It is due to the heat transfer of the preformed specimen's side face and the fact that each center part of the cross-section has a higher average temperature than other parts. The calculated value is in good agreement with the measured value, and the error is no more than 2%.

APA, Harvard, Vancouver, ISO, and other styles

50

Głogowski, Michał, Przemysław Kubiak, Szymon Szufa, Piotr Piersa, Łukasz Adrian, and Mateusz Krukowski. "The Use of the Fourier Series to Analyze the Shaping of Thermodynamic Processes in Heat Engines." Energies 14, no. 8 (April 20, 2021): 2316. http://dx.doi.org/10.3390/en14082316.

Full text

Abstract:

The article presents the application of the Fourier series to theoretical considerations on the method of maximum temperature control in thermodynamic cycles of internal combustion engines equipped with an additional independent kinematic system. The analysis assumes that the processes are zero-dimensional and the gases consumed in the engine cycles are perfect, simplifying the considerations for temperature control as a function of the two variables, pressure and volume, of which the volume as a geometric quantity can be completely controlled. In view of this fact, a predetermined temperature curve was assumed, ultimately reducing the considerations of specific volume changes, that is to say a kinematic system that could implement these changes. Moreover, in the analysis of volume changes, a cycle not used so far in the description of internal combustion engines was used. In the next step, the cycle was modified using the popular Vibe function, which was replaced in the theoretical cycle by two isochoric and isothermal transformations. Heat exchange was completely omitted in the considerations, in that it is of secondary importance, ultimately bringing the temperature function to the function of one variable, the angle of rotation of the crankshaft. Then, the kinematics was divided into the kinematics of the crank-piston system and the additional system, which was approximated with five words from the Fourier series, which in the technique correspond, for example, to the system of oscillators. At the end of the article we have explained one of the ways of actual technical implementation using a single nonlinear oscillator, the so-called ACC system equivalent to a few words from the mentioned Fourier series.

APA, Harvard, Vancouver, ISO, and other styles

Journal articles on the topic 'Perfect combustion'

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles