Point Contact Ehl Fast Direct Iterative Algorithm

This dissertation is composed of two parts. They are the study of the numerical algorithm for arbitrary elastic body contact and the study of the numerical algorithm for point EHL.In part one, a new fast algorithm for arbitrary elastic body contact is proposed Based on Boussinesq's force displacement relationship for infinite half-space and the flexibility method of structure analysis, a set of linear equations of contact pressure is formed. The numerical stability of solution procedure of the equations is achieved by adopting block iteration method and reducing the dimension of the equations. Through changing the iteration matrix of the equations with a full element matrix to a band one with sparse elements, the computation efficiency is greatly raised, and also the computation precision is improved. Numerical calculation shows that the new algorithm obtains very satisfied results when the elements of the iteration matrix are about 15%～20% of its full elements.The algorithm proposed in part one is an improvement to the classical algorithm, and which is also a foundation for the part two.Part two studies the fast numerical algorithm of point EHL. Based on the composite direct iterative method, a new iterative scheme for the calculating of point EHL is proposed, and a computer program based on which is developed. A group of different cases of point EHL problems are calculated and the typical characters of point EHL are obtained, which proves that the new algorithm proposed in the dissertation is correct and reliable. Compare with the composite direct iterative algorithm, the new algorithm not only has good accuracy but also has much higher efficiency and more wide- ranging loadThe new algorithm makes an important improvement to the composite direct iterative algorithm, and lays a new foundation for the study of transient point EHL.