New Method of Founding Profile Equations and Pressure Angle Formula to the Cylindrical Cam Mechanism with Slide Roller-Follower

According to existent problems on design and application of the cylindrical cam mechanism with the slide roller-follower, the one correct concept about profile design and pressure angle is presented. Based on this concept, the theoretical profile,practical profile,meshing surface equations and pressure angle formula of the cam mechanism are built up by using opp.rotation analysis and offset surface principle. This method is very simple and clear, and avoids the abstract analysing process in meshing principle. The mathematic models built by this paper can be used to design,manufacture and check this type of cam mechanism correctly, and also create conditions to make deeply meshing property analysis of this mechanism.     

Study on Mechanism of the Reinforcing Effect of Geogrid in Soil Dam

An experimental study on consolidation and drainage of two gravels with different grading was carried out using high - pressure large - scale tri - axial testing facility. A concept of equivalent surrounding pressure is introduced. An analysis was carried out on the effect and mechanism of reinforcement, experimental surrounding pressure and soil properties. Results show that the reinforcement can improve the strength and failure strain of the material and delay the failure of the soil. The effect of reinforcement of soil - gravel depends on the surrounding pressure and weathering of the gravel.     

Simulation of High Pressure Startu Poil Pum Pof Turbine

Dynamic mathematical model, which is based on the character of the 200 MW tubine lbricating oil system, is established by means of modularization. On the basis of dynamic mathematical models, simulation model of the startu Pprocess of hign pressure startu Poil pum Pis created with the Visual Fortran language. The validity of this model has been verified by the simulation experiments and analysis. The simulation helps to forecast the dynamic characteristic to high pressure startu Poil pum Pand have some directive significance to design method of lubricating oil system.     

地下滴灌灌水器出口正压试验研究

通过试验 ,研究了灌水器类型、流量、工作压力和土壤初始含水量对地下滴灌灌水器出口正压的影响规律。结果表明 :灌水器埋入土壤后 ,其出流由于受土壤等因素的限制 ,在灌水器出口处产生了一定的正压 ,该正压随着灌水历时的延长而增大。影响地埋灌水器出口正压的主要因素是灌水器的额定流量和土壤初始含水量     

喷油泵回油压力对油耗测试精度的影响及解决方法

为提高发动机的油耗测试精度，对影响油耗测试精度的主要原因及其解决方法进行了分析研究和试验。试验表明：柱塞式喷油泵的回油压力是影响测试精度的主要原因，用软件消除回油压力信号和用消波器消除回油压力波，是消除回油压力影响、提高油耗测试精度最简便可靠的方法。     

柴油机电控高压共轨喷油系统的应用

燃油喷射系统作为柴油机的“心脏”,其性能好坏直接影响柴油机的性能和工作可靠性。随着人们对柴油机智能化、强度化、经济性和排放性的要求越来越高,燃油喷射系统的研究也越来越受到重视。未来柴油机必须满足更严格的排放法规,而高压共轨系统具有高度的控制灵活性,其已成为降低柴油机排放的主要核心技术之一。为此,介绍了这种喷油系统的构成、工作原理、特点和现状。     

连续可变相位配气机构的设计

设计了一种机械-液压混合控制式相位连续可变配气机构,以一个旋转阀代替了原有的凸轮轴,用液压力开启气门,以内燃机的转速控制旋转阀的位置,从而达到控制配气相位的目的。     

互插式连栋温室风压分布模拟分析

以CFD理论为基础,建立了互插式连栋温室周围空气绕流的数学模型,设定了流体的边界条件,运用Fluent软件对互插式连栋温室的风压分布进行模拟分析。模拟结果表明,风力对温室作用主要是向上的升力;风压系数沿温室跨度方向分布的数值模拟结果与风洞试验结果基本吻合;上风向和下风向风压系数沿温室高度方向呈二次曲线分布,相关系数分别为0.975和0.990;最后将模拟得到的风压系数转换成相应的风载体型系数,为结构优化设计提供参考。