By Dominique Bonneau, Aurelian Fatu, Dominique Souchet
This sequence offers the required parts to the improvement and validation of numerical prediction versions for hydrodynamic bearings. This ebook describes the thermo-hydrodynamic and the thermo-elasto-hydrodynamic lubrication. The algorithms are methodically special and every part is carefully illustrated.
Read or Download Thermo-hydrodynamic lubrication in hydrodynamic bearings PDF
Similar machinery books
Lifts, elevators, escalators and moving walkways/travelators
"Lifts, Elevators and relocating Walkways/Travelators" covers standards, analyses and designs of assorted sorts of lifts (elevators), escalators and travelators (moving walkways). It includes of 4 sections beginning with a common creation to sorts of lifts, escalators and travelators. part II bargains with the making plans, research and layout of parts or parts of lifts/elevators.
Machining and machine-tools: Research and development
This ebook is the 3rd within the Woodhead Publishing experiences: Mechanical Engineering sequence, and comprises prime quality articles (full examine articles, assessment articles and case experiences) with a unique emphasis on study and improvement in machining and machine-tools. Machining and computer instruments is a vital topic with software in different industries.
Mechanisms of flat weaving technology
To create an efficient woven cloth a strategy engineer needs to decide on the fitting kind of weaving desktop and be sure the actual parameters of the elastic approach of material formation to be utilized. it's also necessary to understand the aim of the entire mechanisms of the selected kind of weaving computing device.
- Performance-Based Gear Metrology: Kinematic-Transmission-Error Computation and Diagnosis
- Gear Materials, Properties, and Manufacture
- Wind Power Electric Systems: Modeling, Simulation and Control
- Centrifugal Pumps
- Leak-Free Pumps and Compressors Handbook
- Probability Applications in Mechanical Design (Dekker Mechanical Engineering)
Additional resources for Thermo-hydrodynamic lubrication in hydrodynamic bearings
Example text
The level 3 loop consists of the search for the partition of the domain into active and inactive zones. For the stationary case presented in this section, the number of pseudo time steps (level 1 loop) is fixed at 10 and the number of thermal iterations (level 2 loop) is fixed at 5. For the first pseudo time step, the search for the first partition (level 3 loop) requires nine iterations. After this, 3 level iterations are required for each change of the time step and only one for the following temperature changes (level 2 loop).
If the calculation hypotheses are those of mixed lubrication, zones with a contact pressure that is not equal to zero can appear. In these zones, the dissipated energy must merge with the energy that results from friction between the asperities of the roughness. 26] 36 Thermo-hydrodynamic Lubrication in Hydrodynamic Bearings where f is the friction coefficient between the two solids making up the walls, u1 and u2 are the respective velocities of these walls (we assume here that there is no relative velocity in the z axial direction), h is the distance between the mean surfaces of the rough walls and pc is the contact pressure (see Chapter 3 of [BON 14b] for more details).
2. Decentered weighting functions. One-dimensional case Each function is of the form: Wi (ξ ) = N i (ξ ) + α F (ξ ) ; Wi (η ) = N i (η ) + β F (η ) ; Wi (ζ ) = N i (ζ ) + γ F (ζ ) where α, β and γ are decentering coefficients, which depend on the Péclet number Pe, and thus, respectively, on the components u, v and w of the velocity corresponding to the three directions x, y and z of the element, of the density ρF, of the specific heat Cp F, of the conductivity kF of the fluid and of the dimensions Δx, Δy and Δz of the sides of the element [HEI 77]: ⎛ α = sign ( u ) ⎜ coth ⎝ u ρ F C pF Δ x Pex 2 ⎞ − ⎟ , Pex = 2 Pex ⎠ kF ⎛ ⎜ ⎝ Pe y ⎛ Pez 2 ⎞ − ⎟, 2 Pez ⎠ β = sign ( v ) ⎜ coth γ = sign ( w) ⎜ coth ⎝ 2 − 2 Pe y ⎞ ⎟; ⎟ ⎠ Pe y = v ρ F C pF Δ y Pez = kF wρ F C pF Δ z kF where sign(u), sign(v) and sign(w), respectively, give the orientation of the flow in the directions x, y and z.