Elastic Cylindric Shell Hydrodynamic Gas Bearing Supported by Wave-formed Foil (Bump Foil) (Ⅱ)——The Frictional Power Loss Test and Its Parametric Investigation

Obtains the theoretical errors of specific frictional head loss including 42.56% for laminar flow, -12.77% for critical area, 8.51% for turbulence smooth area, smaller than 8.51% for turbulence transition area and neglectable error for turbulence rough area.

The results showed the frictional coefficient of the prepared material was stable ,around 0.35±0.05 ,frictional loss was 1/2—1/4 less than that of common asbestos friction material ,and the cost was decreased by 1/3—1/2. The friction material was already applied to YWZ— 630/201 and YWZ— 800/320 brakes, Volga and Beijing cars, and run well without noise.

③ The retention force of cast post and the bonding strength of ZPC declined with the increasing of convergence angles of the post. For the parallel post (convergence angle=0°),the retention force was 321.60 N,the frictional force was 302.559 N,retention force per unit area was 2.976 N/mm2,frictional strength was 3.885 N/mm2;

The results show that 1) the contact stresses exhibit the real power type singularities -1/2± β in the edge of the contact zone for the frictional contact problem with β determined by the material constants of the quasicrystal and the static frictional factor;

The elastic frictional contact problem of the wheel-rail curve negotiation is solved by using the parametric variational principle, the corresponding finite element parametric quadratic programming method and multi-substructure technique to avoid semi-space assumption in traditional wheel-rail contact theory.

Frictional coefficient of PAPER/AL/PE film was measured on different surface and different direction,and the data was analyzed and compared with these different ingredients,thus the frictional coefficient of this new material could be better understood.

Problems of frictional contact, viz. , a nonsmooth equations model and its nonsmooth method for two-dimensional frictional contact problems are studied.

The main characteristic targets were that the tensile strength was 50 - 60MPa, the notch impact strength ≥12kJ/m2, the frictional coefficient was 0.20 - 0.30. The accuracy grade of small mould number gear (m=0.5, Z=72) by this blend could be Grade 7 (See GB2363- 80).

The obtained frictional coefficient is 0.485 at Shengou, 0.57 at Guanchang, 0.556 at Nanma, 0.75 at Zoli, 0.41 at Dingxiling, 0.33 at Xiataoyuan, and 0.705 at Butterfly Spring.

A fourth-order variational inequality of the second kind arising in a plate frictional bending problem is considered.

Calculating frictional force with considering material microstructure and potential on contact surfaces

A method based on the energy dissipation mechanism of an Independent Oscillator model is used to calculate the frictional force and the friction coefficient of interfacial friction.

The relationships between frictional force and parameters of a tribo-system, such as surface energy and microstructure of interfacial material, are set up.

The calculation results of the known experimental data denote that the frictional force is nearly proportional to the surface energy of the material, nearly inversely proportional to the scaling length, and independent of the lattice constant.

The present paper treats the compression of a rectangular block between two parallel rough plates as a problem in the theory of plane strain for perfectly plastic-rigid materials.At first, the plastic-rigid theory of plane strain was outlined, then, the solution to the present problem is briefly surveyed. In section 4, the case that is left out in the present literature, viz. when the width-height ratio lies between 1 and 3.64 for partially rough plates is solved. In this treatment, the coefficient of friction...

The present paper treats the compression of a rectangular block between two parallel rough plates as a problem in the theory of plane strain for perfectly plastic-rigid materials.At first, the plastic-rigid theory of plane strain was outlined, then, the solution to the present problem is briefly surveyed. In section 4, the case that is left out in the present literature, viz. when the width-height ratio lies between 1 and 3.64 for partially rough plates is solved. In this treatment, the coefficient of friction ν is considered as constant along the contact surfaces. For eachμ, a critical value of the ratio w0/h is given. When w/hfrictional force is put to full use. In this case, there is no slip along the contact surfaces and the solution is the same as if the contact were perfectly rough.When w0/hfrictional angle shown in Fig. 3, the slip line field can be constructed in a similar manner as initiated by A. F. Green (ref. 5). In the present case, however, a new parameter connected with μ should be added and the semi-inverse type of construction becomes very complicated.For w/h, the construction is again straightforward. The graphical construction used is described in detail in Appendix Ⅱ.The results of the solution are expressed in terms of Figs. 6 and 7, which show respectively: the average pressure on the plates vs. the width-height ratio for different values of μ and the pressure distributions along the plates. Although the construction for the intermediate case, w0/hfrictional angle connected with μ(Eq. 11).Finally, a short discussion on the graphical construction used for the case of constant μ is given in Appendix Ⅱ.

In this paper a 4-roller two-zone apron type super-high drafting apparatus is introduced. Considerations under which this apparatus was designed, like drafting capacity, method of controlling fibre motion, type of mechanism, etc., are described in detail. The emphasis is laid on the distribution of zone of frictional force before and after the roving entering each drafting zone. The importance of collectors in super-high drafting apparatus is thereby examined from this point of view, and the factors of...

In this paper a 4-roller two-zone apron type super-high drafting apparatus is introduced. Considerations under which this apparatus was designed, like drafting capacity, method of controlling fibre motion, type of mechanism, etc., are described in detail. The emphasis is laid on the distribution of zone of frictional force before and after the roving entering each drafting zone. The importance of collectors in super-high drafting apparatus is thereby examined from this point of view, and the factors of their design exploited。 The results of its preliminary tests are described. It can be seen that the spinning test for 23~S english counts gives optimistic results though further tests are still required. Factors influencing the design and spinning conditions in this drafting apparatus are discussed at the end of this paper.

The contact surface in plastic deformation is considered as a field, whose field-line is given by the "generalized rule of gradient" based upon the condition of least resistance applied both to effective and ineffective direction of "relative" slip on solid and liquid surfaces, as shown by equation (1),which is the formulation of the sta tement that the direction of field-lines is the direction of (most rapidly) decreasing frictional resistance [equation (2) ]. The main results are: