Research of Energy Saving and Environmental Protection Device in the Internal Combustion Engine Intake System

Transcription

1 Research of Energy Saving and Environmental Protection Device in the Internal Combustion Engine Intake System Minliang Zhang 1, Rong Wang 2, Yuan Tian 3, Dean Ji 4 1, 2, 3, 4 College of Mechanical Engineering, Shanghai University of Engineering Science, Shanghai , P. R. China 1 zhanglq2009@126.com, 2 rongwang@126.com, 3 yuantian@163.com, 4 deanji@163.com Abstract - The objective of the research is to optimize the parameters of ozone in the internal combustion engine combustion process and to investigate the structural design method of energy saving and environmental protection device in the internal combustion engine intake system. According to the engine speed and the accelerator parameters, using computer controlled composite tungsten metal circular multi-point ozone occurring sheet, it is achieved that the content of zone in the load and intake system of the internal combustion engine is coordinated and matched, so that the combustion engine can operate at optimum state, reduce emissions of polluting gases and protect the environment. Keywords - Internal combustion engine, energy-saving devices, design method, environmental protection 1 INTRODUCTION The main energy consumed by internal combustion engine is from petroleum products, including gasoline, diesel oil, etc. The demand for oil has been substantially with the development of the economy, which has in turn driven up the price. However, oil will not be able to quench this thirst because it is non-renewable energy sources. Nowadays, petroleum products (gasoline, diesel) are still the main fuel for internal combustion engine since so far no breakthrough has been made to replace the current technologies. At present urban air pollution is mainly motor vehicle exhaust pollution, and the trend is becoming more and more serious. Energy saving, environmental protection is the effective way to delay the crisis, at the same time it is urgent to develop new energy actively. Yin Shi Ren et al invent an energy saving electronic device in the internal combustion engine using corona discharge to produce ozone in 1990s(Yin et al., 1994). Bai Minli and other people developed the ozone generator using the high-frequency pulse along the surface discharge technology and did related experiments. They considered that ozone could realize energy saving and emission purification because of its role of burning strengthen in the internal combustion engine (Bai et al., 1999). Fu Jun and other people used commercial ozone generator for diesel engine to provide intake containing ozone to reduce particulate emission. The experiment showed that ozone had some effects in reducing particulate emission when diesel engine in the medium or low speed(fu et al., 2006). Nasser et al placed a plurality of discharge electrodes in the engine intake, oxygen molecules in the feed gas was ionized the formation of ozone molecules by corona discharge. But there is no actual use of the precedent so far, the reason is: the absence of long-lived ozone-chip dynamically matched with the internal combustion engine operating parameters; This article will research and design the best parameters and structure of energy saving and environmental protection device in the internal combustion engine intake system to solve the problem of making use of ozone using in the intake system of internal combustion engine. 2 PRINCIPLE AND EMISSION OF INTERNAL COMBUSTION ENGINE Internal combustion engine mainly use gasoline, diesel oil as the main fuel. Gasoline, diesel oil is mainly composed of hydrocarbons, trace additive and impurities such as sulfur. Internal combustion engine exhausts carbon dioxide, water, the remaining oxygen and nitrogen when completing combustion under the ideal condition (Check chemical equation 1). Internal combustion engine exhausts carbon dioxide, water, carbon monoxide (CO), hydrocarbons (HC), nitrogen oxide compounds (NOx), sulfur dioxide (SO 2 ), particulate matter PM and aldehydes and so on when incomplete combustion (Check chemical equation 2). They are the harmful parts of emissions. Most of these are poisonous, or have strong irritant, smelly and carcinogenesis. The toxic substance is one of the important sources of air pollution and exist 1% in diesel engine emissions and about 5% in the gasoline. It has become the key point and difficulty in controlling air pollution with the increasing number of internal combustion engines and expanding trend. Chemical equation of completing combustion under the ideal condition: CnHm+ (n+m/4) O (n+m/4) N 2 =nco 2 + (m/2) H 2 O+3.76(n+m/4) N 2 +Heat (1) Chemical equation of incomplete combustion: CnHm+ (n+m/4) O (n+m/4) N 2 =(n-α-β)nco 2 +(m/2 α/2) H 2 O+[3.76(n+m/4) - δ/2]n 2 +αhc+βco+δnox+heat (2) 10

2 Check from the above combustion chemical equation: Coefficient α, β determine the complete extent of combustion in the internal combustion engine, number of producing hydrocarbons and carbon monoxide and have a direct impact on the combustion efficiency and the power in the internal combustion engine when in completing combustion. It is not only affecting the internal combustion engine efficiency but also as an important indicator of internal combustion engine measuring the level of environmental pollution together with δ. Consequently it is an important research direction in energy saving and environmental protection in the internal combustion engine to improve the combustion efficiency and minimize the value of α, β, γ to reduce emissions of pollutants. 3 PRINCIPLE OF ENERGY SAVING AND ENVIRONMENTAL PROTECTION DEVICE IN THE INTERNAL COMBUSTION ENGINE INTAKE SYSTEM Internal combustion engine intake system is composed of ozone generator module, roundness multi-point ozone generator piece, high-frequency power, controller (Fig.1). The system is assembled between the internal combustion engine intake manifold and air filter, roundness multi-point ozone generator piece produce ozone and heat by corona discharge derived by the high frequency high voltage when air goes through the ozone generator components from the intake pipe of the engine. The gas mixes with the fuel thoroughly and consumes energy by combustion in the engine after removing the impurities and dust through the filter. Signal acquisition device transfers engine speed, throttle parameter to the controller. Controller controls high frequency voltage, time of energization and energizing points of roundness multi-point ozone generator piece according to the operating condition of the engine. Roundness multi-point ozone generator piece Filter Ozone generator module Engine Exhaust Intake Outlet air pipe high-frequency power Intake pipe Exhaust Communication cable Controller Fig.1 Energy saving and environmental protection device in the internal combustion engine intake system 4 INTAKE SYSTEM OF AN INTERNAL COMBUSTION ENGINE ENERGY-SAVING DEVICE DESIGN 4.1 Determination of the ozone component work parameters Theoretically, the higher the concentration of Ozone combustion-supporting is better, but actual in intake system of internal combustion engine using gas are air. Therefore, the Ozone concentration will not be higher than the oxygen concentration of the air 66%, the air concentration of 13.6 %( Liu et al., 2007). According to the study, when the ozone generation sheet parameters determination, the effect of ozone yield factors mainly include: voltage, frequency, ozone generator power supply performance, air temperature, humidity, flow, ozone generator sheet temperature rise factor. In practical application, internal combustion engine intake air amount is based on the internal combustion engine design parameters, with the engine speed changes, the control of ozone generation assembly at both ends of the voltage, frequency control of electric field strength, then control the ozone yield (Wei et al., 1998). Experimental results show that the assembly of composite tungsten metal ceramic surface Ozone generation in a fixed air flow, the Ozone production and the strength of electric field is in the linear law of growth, when more than Ozone generator rated output of 10%, with the electric field strength increasing, the production began to decline dramatically. The reason is that the temperature of Ozone generation sheet rise and speed up the Ozone decomposition; the Oxygen in the air and the Ozone generation sheet corona area will occur under saturation situation. In this case, continue to increase the electric field strength cannot increase the ozone output, instead of making the ozone generation sheet work environment is bad, it should choose the ozone generator rated output 85% to 100% as the actual application parameters. + 12V - 11

3 Fig.2 The design steps of energy saving and emission reduction in internal combustion engine air intake system Fig.3 Round-multi point ozone-sheet sections 4.2 The determination of Circular multiple composite tungsten metal ozone generator parameters The device of core is circular multiple composite tungsten metal ozone generating (Fig3). It composed by the inner and outer insulating ring and composite tungsten metal ceramic ozone generating sheet. The main parameters is rated output of Ozone(O3e),the outer ring are installed inside diameter(d),an effective air ventilation area(s),the inner circle diameter(d)and The number of ozone generation sheet(n). The actual amount of ozone demand (O 3 s): O3s=K Qmax (mg) (3) In Formula, Qmax-the maximum intake air quantity of Internal combustion engine M3(Standard atmospheric pressure, Temperature of 20 degrees); K-Calculated ozone concentration, Kz=550 PPM[2]; The actual output of the ozone generator: O3c=Os Kz (mg) (4) In Formula, Kz-The ozone generation sheet output adjustment coefficient, Kz=1.2. Ozone generator inner circle diameter: d= Kj n/π The ozone generation sheet number: n= O3c / O3p (5) In Formula, Kj-Air breakdown safety distance (it determined by the structure and the ozone power supply output voltage) O3p: Single point of the Ozone generation sheet production. 12

4 The installation diameter of Ozone generator external circular: D=d+w+c (mm) (6) In this formula, C-the diameter structure coefficient of Ozone generator (take 6 mm), w-the width of monolithic ozone generating sheet. The diameter of circular multiple composite tungsten metal ozone generation plate simultaneously needs to satisfy high frequency high voltage electric two-phase safety distance and ozone generator gas within the minimum flow rate requirement: The area of ventilation circular ring in Ozone generators=(d 2 -d 2 )π/4 mm 2 The rate of gas flow in Ozone generator: V=Qmin/10-6S Vmin m/s (7) Qmin-The minimum air volume of an internal combustion engine m3/s; S-the circle effective ventilation area(m 3 ); Vmin-To ensure the normal work of the ozone generator minimum velocity of gas flow(it determinate by the circular multiple composite tungsten metal ozone generating sheet heat balance calculation). If the value of D does not meet the requirements of type (7), it is needed to adjust the diameter of D, d value. while V, D, d value cannot meet the need of the need to use a tandem circular multiple ozone generating sheet structure, calculation method is similar in above. 4.3The determine of ozone generator power Rated Power voltage frequency, determined Rated Power: W=1.3Wd n (8) W d - (Single generator rated power W) Rated voltage: 3500±20V; frequency: 15k~20 khz, the frequency and voltage can be dynamically adjusted with the engine work. 4.4 Control system design In the work of an internal combustion engine, the intake air quantity in the intake system is an important parameter of pre combustion, emissions, efficiency, and power influence, it controlled by ECU. The ECU controls the intake parameter is a parameter in the air state, when the intake air with ozone, which the amount of air required to effect on ozone control results of the ECU control parameter adjusting, in order to adapt to the ozone containing gas environment, enable the engine to achieve the optimal burning state. In order to make the ozone in the air intake in the content with the operation of the internal combustion engine to adjust the situation, to achieve the best running state. The mainly on the basis of speed and the throttle signal provided by the ECU to control the Ozone generation sheet electric voltage, frequency increasing electric field intensity and corona frequency so that the intake system of the Ozone content to achieve the best value (Fig.4). Fig.4 block diagram of the control system 5 EXPERIMENTAL ANALYSES Application of the above design method is a design and manufacture of the intake system of energy-saving device. A performance experiment on S1100A2 diesel engine is done and the results as follow. 5.1 The main parameters of the experimental diesel engine 13

5 Experiment for S1100A2 type single cylinder, four-stroke, water-cooled, direct injection diesel engine. Its cylinder s diameter is 100 mm; piston stroke is 115 mm, compression ratio is 20, rated speed is 1500r/min and rated power is 12.1kw. 5.2 Analysis of experimental results Fig.5 is the curve between ozone and fuel consumption rate. From the chart data can be seen that there is fuel saving effect in each test condition. Generally saving rate is between 13% and 24%, the average saving rate is 16%. Fig.6 is the curve between ozone and carbon monoxide emissions. From the chart, we learn that ozone can make an apparent decline in carbon monoxide emissions, about 20% in average. Fig.7 is the curve between ozone and hydrocarbon emissions. Because ozone can support combustion, there is a great decrease in hydrocarbons emission, about 42% in average. Fig.8 is the curve between ozone and soot emission. It shows that soot emissions go down about 3% in average due to blending a certain concentration of ozone in the engine intake. Fig.5 the curve between ozone and fuel consumption rate Fig.6 the curve between ozone and carbon monoxide emissions Fig.7 the curve between ozone and hydrocarbon emissions 14

6 Fig.8 the curve between ozone and soot emissions Fig.9 the curve between ozone and nitrogen oxide emissions Fig.9 is the curve of ozone on nitrogen oxide emissions affecting the load characteristic. It shows that the amount of nitrogen oxides decreases by about 4% due to ozone when load is below 63%, while it increases about 3.5% when load is higher than 63%. 6 CONCLUSIONS The correct method of energy saving device research and reasonable parameters, which can save energy effectively and reduce the amounts of carbon oxides and hydrocarbons in the exhaust, However, there is a slight upward trend towards the amount of nitrogen oxides when load is heavy. But the decline rate of carbon oxides and hydrocarbons is much higher than elevated rate of nitrogen oxides. According to the data of best ozone concentration experiment and different models, choosing appropriate fuel supply and the intake air flow rate, there will surely be a best match of fuel consumption rate and emission and obtain optimal combustion effect. Besides, due to the use of the internal combustion engine is divided into fixed (engine generator sets) and mobile type (automotive engine). Mobile internal combustion engine intake system ozone films can not rely on media such as cooling water, etc. and the airflow cooling makes better. Therefore, a further research on ozone-chip which has a better effect of heat transfer, high ozone production rate and low energy consumption, and high performance power is needed in the future. ACKNOWLEDGMENT The project gets special funding from technological innovation key project Research of energy saving device in the internal combustion engine intake system (10ZZ124) of Shanghai Municipal Education Commission. References Bai Minli, ZHU Guozhao, Li He etc. Ozone strengthen the internal combustion engine combustion research [J]. Internal Combustion Engine Engineering No (in Chinese). Bai Minli,Li He. Journal of Dalian University of Technology [J]. 1997, 37(6): 20~23 (in Chinese). Fu Jun, WANG Yukun, Zhou Dianchun. Electromechanical product development and innovation [J]. 2006,19(1). Hu Youping,BAI Xiyao etc. High-voltage corona discharge to produce ion research. Journal of Dalian Maritime University [J].2004,30(3). Li Qingquan,FANG Xinzhen etc. Along the face and the electrical characteristics of dielectric barrier discharge. Advanced Technology of Electrical Engineering and Energy [J]. 2012,31(1). Liu Changle. Principles of the Internal Combustion Engine[M]. Huazhong University of Science and Technology Press, 2007:74~75 (in Chinese). 15

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