Simulative and experimental investigation of tribological contact cylinder block - valve plate of axial piston machines

本课题的研究内容和目标是深入了解液压轴向柱塞机缸体与配流盘之间的摩擦学接触。为了达到这一目标，应该开发和建立一个模拟程序。模拟结果应与试验台测量结果进行比较。在项目阶段，应首先完成模拟程序的建立。对于这项任务，可以利用IFAS的大量初步工作和经验。该模拟程序将是一个独立的应用程序，它允许在短的模拟时间内对差距和基本物理部件的变形的奥尔兹方程进行组合模拟。目前还没有商业程序允许这种模拟。在项目阶段，模拟应逐步改进，为了验证模拟结果，应在IFAS设计和建造一个测试台。试验台不仅应用于验证模拟程序，还应用于研究活塞-气缸接触的改进材料或几何形状。研究目标可概括如下：-模拟气缸体和阀板之间的粘性和混合摩擦，最好具有良好的精度，-获得有关此摩擦接触磨损的知识，-更换此接触中的黄铜机械部件并使用PVD或其他涂层，-研究几何形状的变化以减少摩擦损失并提高机器的寿命和效率。

Contents and target of the project is a better understanding of the tribological contact between cylinder block and valve plate of an hydraulic axial piston machine. To reach this target, a simulation program should be developed and set up. The results from the simulation should be compared to test-bench measurements.During the project phase, the build-up of the simulation program should be accomplished first. For this task, a lot of preliminary work and experience at IFAS can be used. The simulation program will be a stand-alone application, which allows a combined simulation of the Reynolds-equation for the gap and the deformation of the essential physical parts in a short simulation time. There are no commercial programs available, which allow this kind of simulation. The simulation should be improved stepwise during the project phase.To verify the simulation results, a test bench should be designed and constructed at IFAS. The test-bench should not only be used to verify the simulation program, but also to investigate modified materials or geometries of the piston-cylinder-contact.The research targets can be summarized as follows:- Simulation of viscous and mixed friction between cylinder block and valve plate, preferably with a good accuracy,- Gain of knowledge about wear at this tribological contact,- Replacement of machine parts of brass in this contact and use of PVD- or other coatings instead,- Investigation of changes in geometry to reduce friction losses and to improve the lifetime and efficiency of the machine.