Screw compressors are at present a widely used means of compressing air, process gas and refrigerants. Computer simulation programs, verified by experimental data and improved by recent advances in mathematical analysis, form a powerful tool for process analysis within these machines and hence for a comprehensive check of innovative suggestions and design optimisation. One consequence of this i...

Metalworking fluids (MWFs) are harmful to the environment and to the health of workers, resulting in pressures to re-design them in accordance with sustainable manufacturing principles. In this paper, we review research being performed at the University of Michigan to minimize the life cycle environmental and health impacts of metalworking fluids while simultaneously improving manufacturing per...

We study the lubricated (wet) contact mechanics of a smooth hard cylinder sliding on a randomly rough nominally flat surface of a linear viscoelastic solid. We calculate the rolling and sliding friction, and study the transition from the boundary lubrication to the elasto-hydrodynamic lubrication regime. For the viscoelastic contact the minimum (average) separation does not monotonically increa...

FRICTION AND LUBRICATION in sheet metal forming are influenced by such parameters as material properties, surface finish, temperature, sliding velocity, contact pressure, and lubricant characteristics. The parameters that affect friction and lubrication are schematically shown in Fig. 7.1. Depending on these parameters, the performance of a lubricant and the coefficient of friction (COF) vary. ...

Contents 1. Introduction 2. Stress-induced lubricant degradation 3. Basic equations governing the fluid elastohydrodynamic lubrication (EHL) of line and point contacts 3.1. Equations of fluid motion 3.2. Contact surface displacements in line and point lubricated contacts 4. Steady isothermal EHL problems for lightly loaded non-conformal line contacts 5. Steady isothermal EHL problems for heavil...

Sammanfattning List of publications Summary of papers

A special phonomenon of self-lubrication compensation named hole-wedge effect was found in a bionic porous friction pair, meanwhile the origin and regularity of this effect and its tribological behaviors were discussed in this paper. The process of self-circulating compensation of lubrication was modeled, and taking ferrofluid as lubricant a series of experiments were designed and done. Researc...

Nowadays, the environmental concern in machining industry is a fact. Because of that, in this article a new cooling-lubrication system which combines CO2 cryogenic and MQL technologies is presented. The aim of this new cooling-lubrication system is to offer an ecological and economic efficient alternative. Two nozzle adapters are proposed with different CO2 outlets. The developed nozzles are Pl...