Experimental study about the influence on the actual power usage of ceramic materials in the construction of spark ignition engines

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1 Experimental study about the influence on the actual power usage of ceramic materials in the construction of spark ignition engines Ioan Radu Şugar 1*, Mihai Banica 2 Abstract: In recent years, the issue of the type of material that should be used has always drawn the attention of specialists in engine construction. Due to the success achieved in the study of metals and materials, there have also been remarkable results in engine construction. Ceramic materials could be a solution. Keywords: materials, ceramic, engines, power. 1. INTRODUCTION Automobile and engine manufacturers around the world are making efforts to research and design, aiming to produce advanced internal combustion engines more efficient, which will be used by civilian and military vehicles and in stationary installations. These engines were designed to provide better energy conservation and to reduce emissions by burning fuel more efficiently, issues due to severe restrictions that are imposed by the new legislation. There are several ways to increase the efficiency of a heat engine: isolation chamber, extracting heat from the exhaust gases (through turbo-compound construction) increased exhaust gas temperature, reducing friction etc. Nowadays, designed and developed engines currently use at least one of these methods or, most often, a combination of these, thereby achieving efficient, lightweight, clean (as low emission of pollutants) and adapted to a wide range of uses and powers. The main engine builders in the world are pursuing that aim to bring about the un-cooled engine (insulated) and un-lubricated, which would be a new step in the evolution of engines. In an insulated engine, these amounts of heat can be found in most of the exhaust gases produced by the engine. To improve the engine efficiency it is required a full recovery (as it is possible) of the potential of the heat contained in the exhaust gases. 2. RESEARCH METHODOLOGY 2.1. Turbo-compound engine As the adiabatic turbo-compound engine is concerned, the combustion chamber is insulated, cooling and lubrication systems having smaller dimensions. After turbocharger turbine is placed group stage regenerative turbine, shaft mechanically connected. The research and the development of turbo-compound engine was proposed by R. Kamo. Later research and development of these engines were developed by several companies to determine their ability to reduce exhaust heat and improve thermal efficiency. To improve performance turbo-compound version, there have been made a number of specific changes in the original engine. They refer to redesigning camshaft, valves, cylinder head exhaust ducts, exhaust manifold and turbocharger. These changes were initiated to reduce residual energy losses during the evacuation, while improving the thermal efficiency of the turbine first stage. Turbo-compound engine uses a radial turbine propulsion operating in recuperative system. Mechanical power transmission crankshaft through a gear containing two levels (high and low speed). 67

2 Low speed gear hydraulic coupling includes power transmission and connects effectively the mechanism of power transmission to drive shaft by its flywheel. The use of technical ceramics area is considerably enlarged by participating in the development of composite materials and by covering metal parts with ceramic layers Fig. 1. Turbo-compound adiabatic motor recovery [2]:1-turbocharged, 2 exhaust manifold;3-turbine power, 4-gear;5-vibration damper, 6-PTO shaft Engine with ceramics elements Insulated engine is an objective aiming to achieve in the future the most advanced solution of the main goals in the field of internal combustion engines, namely: reduced fuel consumption, reduced noise and chemicals, increasing durability and reliability, engine downsizing and auxiliaries, reduce production costs. Advantages of special ceramics from conventional materials consist of the following: -main ceramic materials based on widespread sources of nature such as alumina, silicon and its compounds (the most common elements that are found in the earth's crust) or iron oxides, titanium, zirconium (which are times widespread than metals such as W, Mo, Cr, Ni); unlike metal-deficient oxide ceramic energy consumption is achieved with times less; manufacturing-technology ceramics are similar to those used in powder metallurgy, allowing end products at a rate of 90-95% compared to conventional processing of metals which yield obtained finished products is 25-40%. In principle, the development of advanced ceramics technology consists of the following steps [69]: synthesis and processing of dust and making microstructure necessary. Synthesis and processing of dust consists of the following steps: obtaining powder from natural minerals for chemical synthesis; preparing the mixture through addition and mixing. Making microstructure necessary consists of the following steps: training: plastic molding and so on; drying; burning (synthesis); finishing. In addition to procedures based on mechanical methods, it must be disclosed the method based on using a plasma arc, which may also obtain submicrometer particles, which allows subsequent ceramic materials with an extremely fine texture. As it has already been mentioned ceramic materials can form the matrix of the composite, its fibers, or both of them. Figure 2 or presented some ways of reinforcing composites by directing and braiding ceramic fibers [8]. 68

3 Fig. 2. Ways of reinforcing composites byrouting and braiding ceramic fibers [8]: 1-way, 2-way, with unidirectional layers;3-bidirectional in skillet, 4 - simple skillet, 5-by binding triaxial;6-by blending in volume. Interlocking fibers by weaving provides durability in all directions (fig. 2 / 5 and 2 / 6) when a simple stitch (fig. 2 / 4) can not provide a substantial increase in strength and the direction perpendicular to the layers woven. Current technologies allow combining ceramic matrix of any kind with any ceramic fiber (fiber ceramic or metal matrix), the variations are virtually endless, as evidenced by the multitude of materials that occur in an accelerated rate; the explanation is that it is more handy obtaining materials that borrow the desired qualities of the components and in the composites case, the direction of arrangement of fibers, which allow a high degree of anisotropy following the desired directions. Due to the fact that the main task is gas pressure, for the experimental part it will be used alumina without ceramic fibers. Experimental part will be Dacia 1310 engine piston ceramic crown using the same compression ratio. Figure 3 shows the ceramic piston crown used in the experimental part. Figure 4 is the variation in the effective power depending on engine speed for standard standard engine and engine with ceramics elements Table 1 Test results for standard engine and enginewith ceramics elements[8] Nr. crt n, rpm P e,st, kw P e,mod, kw ,75 13, ,79 18, ,76 21, ,14 26, ,20 29, ,78 32, ,54 35, ,70 37, ,15 38, ,07 39, ,10 39, ,88 38,37 69

4 Fig. 3. Piston with ceramic crown Fig. 4. Effective power to engine speed for standard engine [blue curve] and engine with ceramics elements (χ = 1 ) 3.CONCLUDING REMARKS The application of ceramic materials seams ideal: they have a high resistance to high temperature and thermo shocks, they are lighter then the alloys used usual in the engineering of engines, they have better mechanical features in certain working conditions. The ceramic materials can t be a universal substitutes for metals, the main deficiency being their frailty. 70

5 The present phase regarding the use of ceramic materials in the construction of internal combustion engine refers in essence to the technology of elaborating technical ceramics which will be used to isolate pistons, head cylinders, cylinders and valves. In the case of covering with ceramic material of the piston s head, through the increase of covering thickness the heat stream from the head cylinder and the piston drops and the one from the cylinder remain constant to an increase in power of up to 2-3%. Also in the case of the same solutions, we obtain a decrease in the actual specific consumption of fuel by 2,5-3% [8]. REFERENCES [1] Bǎţaga, N., Burnete, N., Căzilă, A., Rus, I., Sopa, S., Teberean, I. (1995). Motoare cu ardere internă. Editura Didactică şi Pedagogică, Bucureşti, ISBN [2] Băţaga, N., Burnete, N., Barabas, I., Cǎzilǎ, A., Filip, N., Naghiu, A., Dan, F. (2000). Motoare cu ardere internă. Combusibili, lubrifianţi şi materiale speciale pentru automobile. Economicitate şi poluare. Editura U.T. Press, Cluj-Napoca, ISBN X. [3] Bobescu, G., Radu, G. Al., Chiru, A., Cofaru, C., Ene, V., Amariei, V., Guber, I. (1998). Motoare pentru automobile şi tractoare. Editura Tehnică, Chişinău, ISBN, [4] Burnete, N.; Băţaga, N., Karamusantas D. (2001). Construcţia şi calculul motoarelor cu ardere internă. Editura Todesco, Cluj- Napoca, ISBN [5] Chiru, A., Anca, H.R., Cofaru, C., Kuchar, R., Soica, A., Ispas, N. (1999). Materiale compozite, vol I. Editura Universităţii Transilvania, Braşov, ISBN X. [6] Oţăt, V., Bolcu, D., Thierheimer, W. (2005) Dinamica Autovehiculelor. Editura Universitaria, Craiova, ISBN [7] Roşca, R., Dăscălescu, D., Tenu, I., Rakosi, E., Manolache, G. (2006). Autovehicule speciale si utilaje. Editura Politehnium, Iasi, ISBN , [8] Şugar, I.R. (2007). Utilizarea materialelor ceramice în arhitectura camerelor de ardere a motoarelor cu aprindere prin scânteie. Editura Risoprint, Cluj-Napoca,ISBN [9] Şugar, I.R., Bănică, M.; Hreniuc, P. N. (2009). Research on Reducing Noise and Chemical Pollution by Internal Combustion Engines. Proceedings of Advanced Manufacturing Operation, Kranevo Bulgaria, ( ) ISSN [10] Şugar, I.R., Butnar, L. A. (2010). Research on growing the competitiveness index of spark ignition engines using ceramic materials. Proceedings of ModTech International New Conference - New face of TMCR Modern Technologies, Quality and Innovation - face of TMCR, Slănic Moldova,( ) ISSN Authors addresses 1 Ioan Radu, Şugar, PhD, Technical University of Centre, Dr. Victor Babes street, No. 62 / A, , Baia Mare, Phone: , e- mail:radusugar@yahoo.com. 2 Mihai Bănică, PhD, Technical University of Centre, Dr. Victor Babes street, No. 62 / A,430083, Baia Mare, Phone: , e- mail: mihai.banica@ubm.ro. Contact Person 1 Ioan Radu, Şugar, PhD, Technical University of Centre, Dr. Victor Babes street, No. 62 / A, , Baia Mare, Phone: , radusugar@yahoo.com. 71