Research On The Point Contact Lubrication Based On The Method Of Capacitance

During practical work, the surfaces of mechanical parts would often be exposed to such high points Lubrication surfaces such as bearings and so on. The particular machine parts often have problems in the period of working time. The reasons are friction and wear.In order to extend the life of the parts, we should have a clear understanding of friction with respect to the special machine parts. For that, a new theory called EHL theory emerged, which focus on such high points Lubrication. It becomes more and more popular on the field of tribology.Many scholars are always involved into this research area, and put forward the hypothesis and theories.In this paper, we consider a lot of relevant literature, and build a point-contact with rotating test rig. According to the test-bed built by our research grope, We construct theoretical model which have Barus and Renolds definition of the viscosity in order to replaced with formula utilized by the Hamrock-Dowson. After that, we imitate the induction-equation method built by Greeks to set a new self-induction equation in order to simplify the calculation and improve the accuracy in regard to theoretical calculation. I compare the results calculated from the Hamrock-Dowson formula and calculated by our theoretical model, purposing to find out the same trend between them. Before doing experiment, we have some prediction related to it. Additionally, the paper uses this test bed to get the diversification trend of film thickness measured by capacitance on the different speed and load caused capacitance variation and the corresponding trend of the minimum film thickness. After that, we calculate the value of the capacitor by r. Image method and the moment method. Additionally, we analyze the reasons of the difference results calculated by r. Image method and the method of moments. Fortunately, we got some considerable conclusions with respect to it. The calculated and measured capacitance values are also compared.Owing to it, we got some conclusions. When the load is constant, capacitance have a gradually decrease. The speed is increasing at the meantime and the magnitude of the increase falls with the speed increase. Comparably, the speed is constant. The capacitance increases while the load increase and the rate increase becomes smoothly with the increase of loads. The speed import relative great influence on the Changes of capacitance value. In contrast, the load has little influence on Changes of capacitance value in terms of load. The calculatingly value of capacitance increase while the minimum film thickness decrease. Father more, if the minimum film thickness increases, the rate of reduces value related to capacitor becomes smaller and smaller. Viscosity-temperature coefficient exert an signifiant influnce on the diffirence between results calculated from the Hamrock-Dowson formula and calculated by our theoretical model. The phenomenon of steep pressure occures In the export zone.The top of steep pressure have a increase and close to the centre of the oil film at the certern load,when the speed increase. The phenomenon of thickness necking occures In the export zone. The area related to thickness necking close to the centre of the oil film at the certern load,when the speed increase.