Thermo-mechanical contact and micro-wear of head disk interface (HDI) are investigated using the improved HDI contact model and theories of frictional heat generation and heat transfer. In analytical simulations, dynamic contact parameters such as material properties, sliding velocity, and surface interference are based on actual HDI design and operation. The resulting contact pressure and temperature distribution show that the micro-wear on the carbon film of a head slider would be significantly attributed to the degradation of carbon material caused by frictional heat generation during sliding contact.

This paper introduces a research oriented numerical model used to simulate the fluid flow in a grinding process. Some of the most important features of the model are described, along with some results obtained. Distributions of temperatures, pressures and flow rates in and around grinding region are obtained in great detail. These results are essential in studying the influence of the fluid on the grinding process, as well as in determining the best fluid composition and supply parameters for a given application. The results agree well with global flow rates and temperature values found in literature and show the feasibility of 3-D simulations in grinding applications.

This work is a thermal simulation extension to the modeling of the fluid flow inside a reservoir-extended porous slider bearing [1]. The bearing system consists of a lubricating film, porous medium, and a reservoir. The velocity flow field generated by the modeling of the fluid flow is used as an input to solve the heat transfer problem. The small parameter used in the asymptotic expansion is the ratio of the reservoir depth to the length of the slider. The thermal effects upon the operation of this system are discussed.

A numerical technique for analysis of heat transfer and thermal distortion in reciprocating sliding components is proposed. In this paper we utilize the Arbitrary Lagrangian Eulerian (ALE) description where the mesh displacement can be controlled independently from the material displacement. A stationary and a moving component are modeled respectively as Lagrangian (mesh displacement equals material displacement) and Eulerian (mesh is fixed in space and material moves through the mesh). The description of the contact between both components accounts for frictional heating and heat exchange.

An advanced three-dimensional model is developed to compute the temperature distribution in a wave journal bearing. The analysis takes into account the heat transfer between the film and both the shaft and the bush. The theoretical results are validated by comparison with experimental data.

Engine designs require better fuel economy, lower NVH, and longer durability. Consequently, the understanding, analysis and design for lubricated engine components that have relative moving surfaces play an important role in this objective. As the GM corporate standard analytical tool for these components, FLARE has been under continuous improvements and validations since its first rollout from GMR in the late 80s. It has also been benchmarked with the best features available in the commercial software package and research literature. There are currently more than 20 standard work procedures directly involving FLARE as solver and its applications span over: • Rod, crank, cam and balance shaft journal bearings; • Connecting rod structure; • Piston structure and scuffing; • Engine mechanical friction; • Load calculation for engine block structural analysis; • Lube system analysis; • Noise analysis. There are three levels of analysis based on requirements. Namely, level one is used in initial design stage that finds solution by interpolating the curve-fitted equations. It requires the least information about the design and runs in seconds. In level 2, a more detailed solution can be obtained by solving mixed mass-conserving lubrication governing equations using FEM with the assumption of rigid bounding surfaces. Heat transfer can be taken into account in this level and above. Level 3 has the full capability, in addition to the features in level 2, the solution is coupled with the elasticity of surface/structure which can be obtained through offline structure FEM analysis. Higher level of analysis captures more physics but requires better understanding of the input parameters and careful interpretation of the results. The unique strength of FLARE is its detailed component level analysis capability. This presentation is an overview of the latest development on FLARE technology. It includes the physics captured in FLARE, integrated solution technique and some selected results for crankshaft bearings, floating piston pins, and piston/liner impact under partial film lubrication.

Lattice Boltzmann method (LBM), is used to examine multi-length scale, confined heat conduction phenomena in solids for which sub-continuum regime is important. This paper describes the implementation of the method and its application to cases pertinent to data storage and electronic devices. Thin solid films with internal heat generation and with temperature difference across the boundaries are used as case studies to illustrate the benefits of the LBM. We compare our results with various hierarchical equations of heat transfer such as Fourier, Cattaneo, and Boltzmann transport equations, as well as with experimental and numerical data from the literature. Our results exhibit a good agreement with other methodologies in one and two dimensions, at a much lower computational effort.

A mathematical model of double narrow spiral grooved seals considering relation of viscosity-temperature, leakage and thermal-conduction is presented. The influences of operating parameters (rotative speed, supply pressure) and configurative parameters (depth of spiral groove) on the basic static characteristics (opening force, leakage, friction torque, temperature rise, and power loss) of double narrow spiral grooved seals are discussed. Comparisons are presented between the measurements and predications for an average 100 mm diameter, high speed, and double narrow spiral groove face seal with water as a test fluid. The theoretical and experimental results show that temperature rise and friction moment of seal faces increase with speed and supply pressure, and change slightly with different spiral groove depths which range from 2μm to 10μm. According to the experimental results and with the reference to the analysis approach of dynamics, an important parameter (separation speed) of the face seal is validated. The theoretical value of separation speed is consistent with its experimental value. This study mainly targets at the design of face seal applied in the Liquid Rocket engine turbopumps using low viscosity lubrications (liquid oxygen, liquid hydrogen). However, its results are also valuable in the design of water-lubricated seal applied in other fields.

By applying the line integral of Barnett-Lothe tensors on oblique planes, the three-dimensional rough surface contact problem for a semi-infinite anisotropic elastic half-plane in contact with a rough rigid sphere is formulated. The steady-state heat transfer condition is assumed and the technique of analytical continuation is employed. The general solutions due to varying degrees of anisotropy and mechanical boundary conditions are obtained.