Steven R. Schmid

Bio: Steven R. Schmid is an academic researcher from University of North Carolina at Charlotte. The author has contributed to research in topics: Lubrication & Tribology. The author has an hindex of 21, co-authored 94 publications receiving 3134 citations. Previous affiliations of Steven R. Schmid include Northwestern University & University of North Carolina at Chapel Hill.

Fundamentals of fluid film lubrication

Abstract: 1: Introduction 2: Bearing Classification and Selection 3: Surface Topography 4: Lubricant Properties 5: Bearing Materials 6: Viscous Flow 7: Reynolds Equation 8: Hydrodynamic Thrust Bearings - Analytical Solutions 9: Hydrodynamic Thrust Bearings - Numerical Solutions 10: Hydrodynamic Journal Bearings - Analytical Solutions 11: Dynamically Loaded Journal Bearings 12: Hydrodynamic Journal Bearings - Numerical Solutions 13: Hydrodynamic Squeeze Film Bearings 14: Hydrostatic Lubrication 15: Hydrodynamic Bearings - Considering Fluid Inertia 16: Gas-Lubricated Thrust Bearings 17: Gas-Lubricated Journal Bearings 18: Hydrodynamic Lubrication of Nonconformal Surfaces 19: Simplified Solutions for Stresses and Deformations 20: General Solution for Stresses and Deformations in Dry Contacts 21: Elastohydrodynamic Lubrication of Rectangular Conjunctions 22: Elastohydrodynamic Lubrication of Ellipitcal Conjunctions 23: Film Thicknesses for Different Regimes of Fluid Film Lubrication 24: Rolling-Element Bearings 25: Additional Elastohydrodynamic Lubrication Applications 26: Non-Newtonian Fluid Effects in Elastohydrodynamic Lubrication 27: Thermo Elastohydrodynamic Lubrication.

Fundamentals of Machine Elements

Abstract: Part I - Fundamentals Introduction What is Design? Design of Mechanical Systems Design as a Multidisciplinary Endeavor Design of Machine Elements Computers in Design Catalogs and Vendors Units Unit Checks Significant Figures Summary Load, Stress, and Strain Introduction Critical Section Load Classification and Sign Convention Support Reactions Static Equilibrium Free-Body Diagram Supported Beams Shear and Moment Diagrams Stress Stress Element Stress Tensor Plane Stress Mohr's Circle Three-Dimensional Stresses Octahedral Stresses Strain Strain Tensor Plane Strain Summary Introduction to Materials and Manufacturing Introduction Ductile and Brittle Materials Classification of Solid Materials Stress-Strain Diagrams Properties of Solid Materials Stress-Strain Relationships Two-Parameter Materials Charts Effects of Manufacturing Summary Stresses and Strains Introduction Properties of Beam Cross Sections Normal Stress and Strain Torsion Bending Stress and Strain Transverse Shear Stress and Strain Summary Deformation Introduction Moment-Curvature Relation Singularity Functions Method of Superposition Strain Energy Castigliano's Theorem Summary Failure Prediction for Static Loading Introduction Stress Concentration Fracture Mechanics Modes of Crack Growth Fracture Toughness Failure Prediction for Uniaxial Stress State Failure Prediction for Multiaxial Stress State Summary Fatigue and Impact Introduction Fatigue Cyclic Stresses Strain Life Theory of Fatigue Fatigue Strength Fatigue Regimes Stress Concentration Effects The Modified Endurance Limit Cumulative Damage Influence of Nonzero Mean Stress Influence of Multi-Axial Stress States Fracture Mechanics Approach to Fatigue Linear Impact Stresses and Deformations Summary Lubrication, Friction, and Wear Introduction Surface Parameters Conformal and Nonconformal Surfaces Hertzian Contact Bearing Materials Lubricant Rheology Regimes of Lubrication Friction Wear Summary Part II - Machine Elements Columns Introduction Equilibrium Regimes Concentrically Loaded Columns End Conditions Euler's Buckling Criterion Johnson's Buckling Criterion AISC Criteria Eccentrically Loaded Columns Summary Stresses and Deformations in Cylinders Introduction Tolerances and Fits Pressurization Effects Rotational Effects Press Fits Shrink Fits Summary Shafting and Associated Parts Introduction Design of Shafts for Static Loading Fatigue Design of Shafts Additional Shaft Design Considerations Critical Speed of Rotating Shafts Keys, Roll Pins, Splines and Set Screws Retaining Rings and Pins Flywheels Couplings Summary Hydrodynamic and Hydrostatic Bearings Introduction The Reynolds Equation Thrust Slider Bearings Journal Slider Bearings Squeeze Film Bearings Hydrostatic Bearings Summary Rolling-Element Bearings Introduction Historical Overview Bearing Types and Selection Geometry Kinematics Separators Static Load Distribution Elastohydrodynamic Lubrication Fatigue Life Variable Loading Summary General Gear Theory Spur Gears Introduction Types of Gears Gear Geometry Gear Ratio Contact Ratio and Gear Velocity Tooth Thickness and Backlash Gear Trains Gear Manufacture and Quality Gear Materials Loads Acting on a Gear Tooth Bending Stresses in Gear Teeth Contact Stresses in Gear Teeth Elastohydrodynamic Film Thickness Gear Design Synthesis Summary Helical, Bevel, and Worm Gears Introduction Helical Gears Bevel Gears Worm Gears Summary Fasteners, Connections, and Power Screws Introduction Thread Terminology, Classification, and Designation Power Screws Threaded Fasteners Riveted Fasteners Welded, Brazed, and Soldered Joints Adhesive Bonding Integrated Snap Fasteners Summary Springs Introduction Spring Materials Helical Compression Springs Helical Extension Springs Helical Torsion Springs Leaf Springs Gas Springs Belleville Springs Wave Springs Summary Brakes and Clutches Introduction Thermal Considerations Thrust Pad Clutches and Brakes Cone Clutches and Brakes Block or Short-Shoe Brakes Long-Shoe, Internal, Expanding Rim Brakes Long-Shoe, External, Contracting Rim Brakes Symmetrically Loaded Pivot-Shoe Brakes Band Brakes Slip Clutches Summary Flexible Machine Elements Introduction Flat Belts Synchronous Belts V-Belts Wire Ropes Rolling Chains Summary Appendices Index

Bone and tissue scaffolding and method for producing same

Abstract: The present invention provides a bone in-growth and on-growth material and method for making a material by bonding porous sheets together. The porosity is controllable from zero porosity to essentially a fully porous material.

Organ Printing: Tissue Spheroids as Building Blocks

Abstract: Organ printing can be defined as layer-by-layer additive robotic biofabrication of three-dimensional functional living macrotissues and organ constructs using tissue spheroids as building blocks. The microtissues and tissue spheroids are living materials with certain measurable, evolving and potentially controllable composition, material and biological properties. Closely placed tissue spheroids undergo tissue fusion - a process that represents a fundamental biological and biophysical principle of developmental biology-inspired directed tissue self-assembly. It is possible to engineer small segments of an intraorgan branched vascular tree by using solid and lumenized vascular tissue spheroids. Organ printing could dramatically enhance and transform the field of tissue engineering by enabling large-scale industrial robotic biofabrication of living human organ constructs with "built-in" perfusable intraorgan branched vascular tree. Thus, organ printing is a new emerging enabling technology paradigm which represents a developmental biology-inspired alternative to classic biodegradable solid scaffold-based approaches in tissue engineering.

Towards Energy and Resource Efficient Manufacturing: A Processes and Systems Approach

Abstract: A B S T R A C T This paper aims to provide a systematic overview of the state of the art in energy and resource efficiency increasing methods and techniques in the domain of discrete part manufacturing, with attention for the effectiveness of the available options. For this purpose a structured approach, distinguishing different system scale levels, is applied: starting from a unit process focus, respectively the multi-machine, factory, multi-facility and supply chain levels are covered. Determined by the research contributions reported in literature, the de facto focus of the paper is mainly on energy related aspects of manufacturing. Significant opportunities for systematic efficiency improving measures are identified and summarized in this area. 2012 CIRP.

Oral processing, texture and mouthfeel: from rheology to tribology and beyond

Abstract: Texture and mouthfeel arising from the consumption of food and beverages are critical to consumer choice and acceptability. While the food structure design rules for many existing products have been well established, although not necessarily understood, the current drive to produce healthy consumer acceptable food and beverages is pushing products into a formulation space whereby these design rules no longer apply. Both subtle and large scale alterations to formulations can result in significant changes in texture and mouthfeel, even when measurable texture-related quantities such as rheology are the same. However, we are only able to predict sensations at the initial stages of consumption from knowledge of material properties of intact food. Research is now on going to develop strategies to capture the dynamic aspects of oral processing, including: from a sensory perspective, the recent development of Temporal Dominance Sensation; from a material science perspective, development of new in vitro techniques in thin film rheology and tribology as well as consideration of the multifaceted effect of saliva. While in vivo, ex vivo, imitative and empirical approaches to studying oral processing are very insightful, they either do not lend themselves to routine use or are too complex to be able to ascertain the mechanism for an observed behaviour or correlation with sensory. For these reasons, we consider that fundamental in vitro techniques are vital for rational design of food, provided they are designed appropriately to capture the important physics taking place during oral processing. We map the oral breakdown trajectory through 6 stages and suggest a dynamic multi-scale approach to capture underlying physics. The ultimate goal is to use fundamental insights and techniques to design new food and beverages that are healthy yet acceptable to consumers.