Chen G.-S.,Tianjin University |
Chen G.-S.,Kunming University of Science and Technology |
Lin T.-J.,Guangxi Yuchai Machinery Co. |
Zhang Q.-C.,Tianjin University |
And 2 more authors.
Neiranji Gongcheng/Chinese Internal Combustion Engine Engineering | Year: 2012
Experimental study on emissions characteristics was conducted in a heavy-duty common-rail diesel engine equipped with single-stage turbocharger (HX35W) and two-stage turbocharger (2TC), to compare engine performance and emissions characteristics under five levels of liter power and explore the technical routes by EGR technology to meet China IV emission regulation. The results show that with liter power increasing, 2TC can obviously improve the trade-off between NO x, soot and BSFC as compared to HX35W under full load low and middle speed conditions. It is very hard for HX35W to reduce NO x to the level lower than the limit value of China IV due to the poor recirculation ability of exhaust gas and excessively high exhaust temperature before turbine. ESC test results show that with reducing liter power, soot and CO weighted emissions decrease and HC emission increases. Under low levels of liter power (23.9, 25.5 and 28.2 kW/L), NO x and soot emissions for HX35W and 2TC are nearly comparable, both boost types enable the engine to meet China IV regulation without any after-treatment measure, but BSFC of HX35W is lower than that of 2TC. With liter power increasing further, it is increasingly difficult for HX35W to meet China IV requirements. However, using 2TC coupled with EGR can still satisfactory China IV without or with a simple after-treatment device.
Chen Y.,Wuhan University of Technology |
Lv L.,Wuhan University of Technology |
Shen J.,Guangxi Yuchai Machinery Co.
Applied Mechanics and Materials | Year: 2014
All future engine developments must consider the primary task of achieving the required emission levels. An important step towards the development of combustion engines is the optimization of the flow in the intake ports. The charging movement in the combustion chamber, which is generated by the intake flow, considerably influences the quality of the combustion engine. In this paper, steady CFD analysis were applied to different structures of double-tangent-port. The swirl ratio can be improved while flow coefficient remains unchanged if port eccentricity is 34.4 mm. By defining three characteristic parameters, the speed non-uniformity index, standard deviation and mixture concentration standard deviation and equivalent ratio range, quantitatively describing the combustion process in cylinder, and then compared with transient CFD threedimensional contours, we can see that characteristic parameters can be more accurate and comprehensive in analyzing the influence of inlet structure of soot formation. Effects of different intake ports on fuel-air mixing in a turbocharged diesel direct injection engine during intake and compression strokes are analyzed. It turns out that the optimized double-tangent-port has the highest uniformity of velocity, in the meanwhile, air/fuel mixing is relatively uniform. On the other hand, mixed-port and double-helix-port can cause uneven flow field which is bad for combustion, even though the swirl ratio can increase largely. Finally, the simulation results show that soot emissions of the optimized double-tangent-port have significantly lower levels, at 2200 r/min under full load. © (2014) Trans Tech Publications, Switzerland.
Chen Y.,Wuhan University of Technology |
Lu L.,Wuhan University of Technology |
Shen J.,Guangxi Yuchai Machinery Co.
Neiranji Gongcheng/Chinese Internal Combustion Engine Engineering | Year: 2015
A computational study on the process of deposit formation in urea injector was performed using a detailed deposit model. The deposit model includes the basic process of wall film formation, evaporation, entrainment, crystallization and by-product formation and incorporates the chemical reaction mechanism of urea thermal decomposition. The simulations of the inner wall temperature and deposit quality inside urea injector were validated respectively by the results of bench test and Thermal Gravity Analysis (TGA), showing a good agreement with experiment data. This indicates that the detailed deposit model can predict the trend of deposit under different working conditions. Meanwhile, a multi-dimensional numerical simulation was made to analyze the process of deposit formation in a urea injector. The result shows that by-product formation or deposit can be avoided by keeping the temperature inside injector below 140°C.The minimum urea injection rates which has no by-product formation are 1000 mL/h and 2000 mL/h respectively when exhaust temperatures are 300°C and 400°C with the same exhaust flow rate of 600 kg/h. ©, 2015, Chinese Society for Internal Combustion Engines. All right reserved.
Lin Z.,Guangxi Yuchai Machinery Co. |
Wang T.,Tianjin University |
Nan G.,Tianjin University |
Zhang R.,Tianjin University
Guangdian Gongcheng/Opto-Electronic Engineering | Year: 2014
In order to obtain three-dimensional data of engine cylinder head blank, a passive line structured light canning measurement system is designed. Calibration of the direction cosine of the movement of camera optical center is given based on principle of virtual binocular stereo vision. Stereo vision system consists of a single camera moving along the one-dimensional rail, which gives Rotation matrix R and Translation vector T between local coordinate system and global coordinate system. And then the origin of local coordinate system is conversion to the global coordinate system so that the line of movement of camera along the rail is fitted and its direction cosine is calculated. Three-dimensional topography of a certain cylinder head is scanned and the cloud data on this topography is obtained, from which the data of Intake port center coordinates is extracted. Finally, the three-dimensional data is dealt with reverse engineering software and surface reconstruction works well.
Huang W.,Guangxi University |
Ou C.,Guangxi University |
Lu H.,Guangxi University |
Xie Z.,Guangxi Yuchai Machinery Co.
Applied Mechanics and Materials | Year: 2011
According to the limit working conditions of the gantry milling machine column, this paper adopts Parametric Design Language APDL to set up finite element model and make finite element analysis. Based on the analysis, the topology optimization method of column structure is proposed, and the optimal design method is established to minimize the weight. The finite element analysis is made again to analyze the rearranged column structure. Compared with the design made through experience, optimally designed column can reduce 10% weight. And the critical displacement and maximum stress are not affected. © (2011) Trans Tech Publications.
Zhang X.H.,Guangxi University |
Su G.C.,Guangxi University |
Han Y.Y.,Guangxi Yuchai Machinery Co. |
Ai X.H.,Guangxi University |
Yan W.L.,Guangxi University
Materials Science and Engineering A | Year: 2010
The mechanical properties of Al-Mg-Si cast alloys with different chemical compositions were investigated using an orthogonal test method. The optimized chemical compositions of Al alloy are given in wt% as follows: 7.0%Si-0.35%Mg-2.0%Cu-0.2%Mn-0.2%Ni-0.1%V-0.8%RE-89.35%Al. The optimized Al-Mg-Si alloy with metal mold casting had excellent mechanical properties. The softening resistance of the optimized alloy was better than that of ZL101 at elevated temperatures. The scanning electron microscopy fractographs of the tensile samples of ZL101 and optimized Al alloy at different magnifications revealed that all the specimens were fractured in a ductile manner, consisting of well-developed dimples over the entire surface. The alloys failed in a mixed-mode fracture, comprised predominantly of transgranular shears and a small amount of quasi-cleavages. © 2010 Elsevier B.V.
Liu C.-L.,Guangxi Yuchai Machinery Co.
Zhuzao/Foundry | Year: 2011
The slagging often occurs on cupola's tuyeres during the melting of compacted graphite cast iron; the tuyeres in the upper row even were blocked, and the coke in the hearth in the area below the upper row of tuyeres was burned empty. To solve the problems above, the reason of slag formation was analyzed from aspects such as the addition amount and kind of flux, cupola wall effect, balance control of wind and coke, etc. The result indicates that the slagging can be decreased effectively through adjusting the angle of tuyeres in the lower row, blast volume and cleaning the tuyeres in time.
Li D.-Y.,Guangxi Yuchai Machinery Co. |
Li Y.-L.,Guangxi Yuchai Machinery Co.
Zhuzao/Foundry | Year: 2016
The cast steel was successfully replaced by the ductile iron in the casting production by the sand-lined metal mold process, and batch production was achieved. The basic process parameters of sand-lined metal mold process were analyzed, and the casting defects in the automobile chassis parts casting were removed. The tensile strength and elongation of the cast-as casting reached more than 600 MPa and 10%, respectively. © 2016, Chinese Mechanical Engineering Society. All right reserved.
Guangxi Yuchai Machinery Co. | Date: 2013-02-01
Drilling machines; mine working machines; earth moving machines; excavators; diggers machines; ore treating machines; hoists; elevating apparatus; bulldozers; road making machines.
Tong S.-Y.,Guangxi Yuchai Machinery Co.
Zhuzao/Foundry | Year: 2013
Using method of mathematical statistics, the data of separately cast test bar mechanical properties of gray iron by use of induction furnace and duplex melting were statistically analyzed. The results show that with basically the same conditions such as casting, alloy grade, the chemical composition, the inoculant addition, the specifications, quality standards and origin of the raw materials, the duplex melting gray iron separately cast test bars have the tensile strength 26.5 MPa and hardness HBW 6 higher than that of induction furnace smelting gray iron, and its metallurgical quality is better too.