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Yin B.,Jiangsu University | He J.,Changchai Company Ltd | Xu Y.,Changchai Company Ltd | Jia H.,Jiangsu University | Liu S.,Jiangsu University
Jiangsu Daxue Xuebao (Ziran Kexue Ban)/Journal of Jiangsu University (Natural Science Edition) | Year: 2011

Taken a light-duty diesel engine as prototype, the influences of post-injection on NOx and soot emission characters, combustion process and fuel consumption were discussed at the operating conditions of low load rate with common speed of 1600 r · min-1. The results show that internal cylinder temperature rises again in the later of main combustion process due to post-injection. With the increasing of the post-injection fuel quantity, the main combustion section cylinder pressure, the maximum combustion temperature, the average combustion temperature and the peak value of the main combustion heat release rate are all gradually decreased. The main combustion section cylinder pressure and the peak combustion heat release rate increase slightly with the increasing of the post-injection interval angle, while the average combustion temperature decreases. At the condition of low load rate, NOx and soot emissions can be efficiently reduced by post-injection and gradually decreased by the increase of post-injection fuel quantity. With the increasing of post-injection interval angle, the NOx emission gradually decreases and the soot emission shows an upward trend after the initial decrease. The fuel consumption is increased by post-injection and the increasing of post-injection fuel quantity and post-injection interval angle.

Dong F.,Jiangsu University | Gong W.,Jiangsu University | Zhang W.,Jiangsu University | Yin B.,Jiangsu University | Sun J.,Changchai Corporation Ltd
Neiranji Xuebao/Transactions of CSICE (Chinese Society for Internal Combustion Engines) | Year: 2015

With respect to a turbocharged diesel engine with liquid cooling system, a visualization study on the vaporliquid two-phase flow and heat transfer in the coolant jacket of bridge zone of cylinder head of internal combustion engines was studied by using the endoscopic high speed photography technology and temperature measurement technique. Experimental results show that there are large number of bubbles in the coolant jacket of bridge zone of cylinder head. The processes of bubble formation, adhesion, diffusion and annihilation were observed at the rated condition. With the decrease of cooling flux, the number of bubble is greatly decreased, while to some extent the size of bubbles is increased. Meanwhile, because of existence of certain degree of boiling heat transfer, the temperatures of measured points in several high heat flux regions don't improve markedly as the sharp drop in cooling flux. In contrast, the temperatures of measured points in low heat flux region are remarkably increased. © 2015, Chinese Society for Internal Combustion Engines. All right reserved.

Sun P.,Jiangsu University | Lu W.-X.,Jiangsu University | Miao Y.-C.,Changchai Co. | Xu Y.,Changchai Co.
Neiranji Gongcheng/Chinese Internal Combustion Engine Engineering | Year: 2011

Three-dimension numerical simulation of flow characteristics of helical intake port was carried out. The CFD numerical simulation method, verified by steady flow test rig, was used to analyze the effects of the helical section structure parameters of intake port on the intake flow characteristics. The results indicate that the helical intake port possesses complex structure, the flow characteristics are affected by many structure parameters of its helical section. Among them, radiuses of transition part and swirl shell, valve guide boss height are the most sensitive parameters.

Pei H.,Jiangsu University | Zheng W.,Jiangsu University | Wang G.,Jiangsu University | Wang H.,Changchai Company Ltd
Advanced Materials Research | Year: 2012

Large quantities of coolant-lubricants are still widely used in metal working industry, generating high consumption and discard costs and impacting the environment. An alternative to current practices is to use biodegradable cutting fluids that doesn't pollute environment or require new setups. In current study, biodegradable base oils, synthetic ester and castor oil, are chosen and compounded into cutting fluids which correspond with the national standards. The tests have been performed to high speed turn AISI 1045 steel in ester-based fluid, castor-based emulsion, kerosene and dry condition. The results indicate that the application of cutting fluids is inevitable in metal machining and can not be replaced by dry machining. The lubricating and cooling properties of the ester-based fluid and castor-based emulsion are better than kerosene and can wholly replace mineral oil.

Cui S.,Nanjing Research Institute for Agricultural Mechanization Ministry of Agriculture | Cao G.,Nanjing Research Institute for Agricultural Mechanization Ministry of Agriculture | Zhang W.,Nanjing Research Institute for Agricultural Mechanization Ministry of Agriculture | Zhu X.,Changchai Company
Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering | Year: 2014

In mechanical rice transplanting, hill-row spacing combination directly influenced the growth and yield of rice. To compare the effect of hill-row spacing on mechanical transplanting rice, the growth and yield of rice, we set up 2-year field experiments located in Zhangjiagang, Jingjiang and the Yellow Sea farm in Jiangsu Province, separately. The rice breed planted in Zhangjiagang, Jingjiang and the Yellow Sea farm was Wuyunjing 29, Wuyunjing24 and Lianjing 7, separately, all of which were japonica hybrid rice. There were 3 row-hill spacing treatments in-at each site, which the row spacing by hill spacing was 30 cm by 11 cm, 25 cm by 14 cm, 25 cm by 11 cm, each repeated 3 times. By the influence of the spacing, the area of 30 cm by 11 cm (row spacing by hill spacing), 25 cm by 14 cm (row spacing by hill spacing) and 25 cm by 11 cm (row spacing by hill spacing) was 135 m2, 150 m2 and 150 m2, separately. At the same site within each treatment, only the row-hill spacing differences were the mutation factors, the other factors were controlled. The effect of the mechanical transplanting rice, the tillering dynamics of rice, yield and yield composition of rice were tested. The effect of mechanical rice transplanting measured immediately after transplanting. 200 continuous points were taken in each area; the number of plants per hole, seedling injury and inverted were recorded to calculate the average number of plants per hole, drain planting rate, seedling injury rate and seedling inverted rate. To determine the tillering dynamic, the number of tillers was counted every 7 days from rice transplanting to the full panicle stage, 20 points for each plot were fixed. Actual yield of rice was determined after ripening. For each treatment, 3 m2 of rice were weighed after harvesting to calculate the actual yield, repeated 3 times. According to the average number of plants per hill, 3 hill plants were selected for testing, and then the yield component and the theoretical yield of rice were calculated. SPSS17.0 and Excel 2007 were used for the statistical analysis. The results are indicated below: 1) Drain planting rate of 25 cm by 14 cm (row spacing by hill spacing) was the lowest, then was 25 cm by 11 cm (row spacing by hill spacing), 30 cm by 11 cm (row spacing by hill spacing) was the highest. These indicate that narrow row spacing large hill spacing was conducive to reducing the drain planting rate of rice. No rule was found from the rates of seedling injury and inverted in between these 3 breeds. 2) The number of tillers after tiller stabilization of 30 cm by 11 cm (row spacing by hill spacing) was the highest, and then was 25 cm by 14 cm (row spacing by hill spacing), 25 cm by 11 cm (row spacing by hill spacing) was the lowest. These indicate that large row spacing and hill spacing is conducive to the promotion of rice tillering. 3) In the aspect of the yield components, ears of 25 cm by 11 cm (row spacing by hill spacing) were the highest, and then were 25 cm by 14 cm (row spacing by hill spacing), 30 cm by 11 cm (row spacing by hill spacing) was the lowest. No rule was found between the grain numbers per spike, the seed rate and 1000-grain weight. Finally in the aspect of the theoretical rice yield and the actual rice yield, 25 cm by 11 cm(row spacing by hill spacing) was the highest, and then 25 cm by 14 cm (row spacing by hill spacing), 30 cm by 11 cm (row spacing by hill spacing) was the lowest. The theoretical rice yields of 25 cm by 11 cm (row spacing by hill spacing) were 9.68%-26.5% higher than 30 cm by 11 cm (row spacing by hill spacing), and the actual rice yields of 25 cm by 11 cm (row spacing by hill spacing) were 3.18%-20.6% higher than 30 cm by 11 cm (row spacing by hill spacing). The 25 cm by 11 cm (row spacing by hill spacing) row transplanter should be more suitable for mechanical rice planting in Jiangsu Province. ©, 2014, Chinese Society of Agricultural Engineering. All right reserved.

Yin B.,Jiangsu University | Huang C.,Jiangsu University | Liu S.,Jiangsu University | He J.,Changchai Co. | And 2 more authors.
Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering | Year: 2012

In order to develop small non-road diesel engines with high-performance and low emission as well, a small non-road direct injection type diesel engine with a single cylinder was taken as the research object. The CAE and CFD comprehensively applied, and the research was proceed with two approaches which were the optimization matching of combustion system parameters and the improvement design of mechanical system. Optimization matching of fuel injection system parameters, combustion chamber and intake swirl ratio were studied by using the multi-dimensional simulation software such as Hydism, Fire and so on. The optimization plan was determined after the effects on combustion process and emission performance were analyzed. The ameliorated design was applied to cylinder block, cylinder head as well as piston, etc. In addition, the finite element analysis software was used. As a consequence, the structural intensity, stiffness and dependability of the diesel engine were enhanced. At the same time, the machine oil consumption reduced effectively. The results of the test showed that, compared with the original engine, the fuel economy and the emission performance were improved effectively. The quantity of CO, HC + NOx and PM reduced by 49%, 58%, 74% respectively, while fuel oil and machine oil consumption reduced by 6.9% and 59%. The emission performance of the optimized scheme was obviously improved which could meet EPA IV Non-road Diesel Engine Emission Limit well. This paper provides a reference for the development of small high-performance non-road diesel engines.

Jia H.,Jiangsu University | Yin B.,Jiangsu University | He J.,Changchai Company Ltd | Xu Y.,Changchai Company Ltd
Qiche Gongcheng/Automotive Engineering | Year: 2015

The law of the effects of injection timing, exhaust gas recirculation (EGR) rate and injection pressure on the combustion process and the pollutant emissions of a four-cylinder diesel engine for light-duty vehicle are comparatively analyzed in this paper. The results indicate that either moderately advancing or retarding injection timing can prolong delayed burning period and hence improve the uniformity of combustible mixture, realizing partial premixed combustion and suppressing soot emissions. Compared with retarding injection timing, moderate advance of injection is more conducive to reducing soot emissions, but is limited by the deterioration of NOx emissions. The introduction of EGR with early injection can not only lower in-cylinder combustion temperature and hence restrain the generation of NOx, but also effectively avoid the problem of too-early combustion phase caused by early injection and thus increase combustion efficiency and improve fuel economy. Effective specific fuel consumption and the emissions of NOx and soot can be concurrently improved in high EGR rate region. But for retarding injection, the introduction of EGR may further exacerbate the phenomena of post-combustion and deteriorate effective specific fuel consumption and soot emission. With the increase of injection pressure, the process of combustion and heat release become slow and the transient peak of heat release rate and average in-cylinder temperature lower and hence the NOx and soot emissions can be reduced simultaneously for moderately advancing injection, while it is just the opposite for retarding injection, the emission of NOx goes up with the rise in injection pressure. However the injection pressure only has trivial effects on effective specific fuel consumption no matter with advancing or retarding injection timing. © 2015, Society of Automotive Engineers of China. All right reserved.

Jia H.,Jiangsu University | Yin B.,Jiangsu University | He J.,Changchai Company Ltd | Xu Y.,Changchai Company Ltd
Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering | Year: 2015

With the sustained development of economy and technology, small non-road diesel engines are extensively applied in industrial and agricultural production. The single-cylinder engines, in particular, plays a crucial role in modern agriculture, working as the main power source for small-to medium-sized tractors and mini-farming machinery etc. Due to current situation of fuel issue in China and structure limitation of single-cylinder diesel engine, a new method is presented to improve combustion and emission performance using internal exhaust gas recirculation (IEGR) in terms of engine internal purification, that is, by adding advance intake profile to intake cam shaft. As for the small-sized non-road diesel engine, an optical engine equipped with the AVL Visio scope consisting of a charge coupled device (CCD) camera Pixel-Fly VGA, an endoscope, illumination device and the AVL-Thermo Vision software was used in order to capture combustion images. In addition, the AVL-Thermo Vision software was applied in the measurement of temperature and soot distribution of diffusion flame. The resolution and frequency of CCD camera were 640×480 pixel and 10 Hz respectively. By means of images collecting and processing for combustion process, together with pressure collecting and emission performance testing, the influences of IEGR on the diesel engine's combustion process and emission performance were analyzed. The results showed that under the conditions of 1760 r/min and 50% load rate, in-cylinder pressure peak decreased from 5.49 to 5.43 MPa, the start of heat release was delayed by 0.5°CA and the maximum instantaneous heat release rate was reduced from 85.7 to 82.4 J/deg when IEGR was introduced. Furthermore, the average temperature of combustion flame was reduced, centering between 1900 and 2100 K. The area of high-temperature intense radiation was reduced, in which the area percent of temperature higher than 2200 K dropped from around 30‰ to below 10‰. That was beneficial to controlling NOx emissions. The average value for KL factor was obviously higher than that for the original engine within the entire range of combustion, the peak of which rose from 40.5 to 67.4. At the speed of 1760 r/min, the NOx emissions decreased within the entire range of load rate, especially under 50% load rate (by 19.6%) when IEGR was introduced. Yet, the soot emissions increased as the load rate was increased and the growing rate became even larger at higher load rate. The soot emissions rose by 49.33% when full load rate was achieved. Another countermeasure, i.e. the fuel supply advance angle, was adjusted to collaboratively optimize engine performance. NOx and soot emissions could be improved simultaneously. When the fuel supply advance angle was extended longer from 8 to 12°CA, for example, NOx emissions rose up but was still improved in relation to that produced from the original engine, while soot emissions were decreased substantially thus better than that of the original in the load range from small to medium. Also, brake specific fuel consumption could get to a relatively low level at partial load rate. Therefore, it is validated that this method has the potential to improve engine performance comprehensively and the present work can provide theoretical basis for the application of IEGR on small-sized non-road diesel engine. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.

Yin B.,Jiangsu University | Yang K.,Jiangsu University | Jia H.,Jiangsu University | Xu Y.,Changchai Co. | And 2 more authors.
Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering | Year: 2013

Based on a 4F20 diesel engine with a mechanical fuel injection system, a high-pressure common rail diesel engine was developed to meet the national stage IV Emission Regulation. The optimization and matching of mechanical, combustion and after-treatment systems were conducted. For the development of the mechanical system, the ribs were added and a separated structure between the cylinder head bosses and the liner was utilized to increase the cylinder block stiffness and to reduce the liner distortion. The geometry of the upper water jacket in the cylinder block was designed to be circular, and its height was increased to match the TDC position of the first piston ring to improve the cooling effect of piston. The installing hole of for the glow plug was added on the base of three-hole layout, and then the coordinates of four holes were optimized. Degassing holes were added at corresponding position in the cylinder head gasket and cylinder head to eliminate dead flow regions and to enhance cooling effect; Coolant passages were set around the injector and above the intake, exhaust ports, and the local maximum temperature of cylinder head was reduced from 469.1K to 457.8K according to the optimized results. A new type of double row gear transmission system was designed which can run compactly and stably at low noise levels. For the optimization of the combustion system, the precise and flexible control of fuel injection timing and amount as well as split injection strategies were achieved by upgrading the mechanical fuel injection system to the BOSCH CRS2.0 electronically controlled high-pressure common rail fuel injection system. The injection pressure was improved significantly (the max pressure could reach up to 160MPa) as a result of the upgrade. The pre-injection can effectively improve the NOx emission about 30% at small and medium load, and low NOx and soot emissions were achieved while maintaining fuel efficiency after the introduction of post-injection at medium load. A big, open shallow combustion chamber was designed and the compression ratio was decreased from 19.7 to 17.5. Fuel spray circumferential distribution was planned according to the principle of equal arc length, also spray axial distribution was optimized, and the ratio of spray coverage volume to effective combustion volume was determined as 54.41%. For the air intake system, a radial-flow turbocharger with an exhaust bleeder valve was chosen to ensure that the compressor had enough safety margins from surge line at low speed, and it could work in highly efficient areas in the medium speed range. After applying the two-stage DOC system whose first and second volume fraction were 25% and 75%, the purification efficiency of CO, HC, SOF and PM reached 90%, 85%, 90% and 20% respectively. The developed diesel engine in this paper was equipped on an NHQ6492V3 SUV. The vehicle emissions test results showed that the emission of CO, NOx, THC+NOx and PM were decreased to 0.36, 0.259, 0.328 and 0.029g/km respectively, which were 20% lower than the national stage IV Emission Regulation limit. The comprehensive fuel consumption was 7.217L/(100 km) and it can meet the Chinese third stage regulation for passenger cars limit which will be implemented in 2015.

Disclosed is a fuel injection control system for a single-cylinder diesel engine, comprising: a set of operating condition sensors including an accelerator pedal position sensor and a cooling water temperature sensor, an input signal interface capable of receiving an input signal from the operating condition sensors, a control unit connected to the input signal interface, and a rotational speed sensor provided at a camshaft or starting shaft of the single-cylinder diesel engine. The rational speed sensor is connected to the control unit via a rotational speed correction circuit. The control system can easily and quickly determine the rotational speed and operating stroke of the single-cylinder diesel engine, so as to quickly determine the fuel injection quantity and injection timing of the single-cylinder diesel engine in real time.

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