The purpose of this module is to provide the student with analytical tools to solve mechanics problems in engineering. Through this the student should gain insight into the complexities of mechanical design and an awareness of the responsibilities of the mechanical design engineer. The student learns through a combination of lectures, tutorials, laboratories, formative assessments, and self-directed learning acquire the skills, knowledge, and professional attitudes needed to design simple mechanical structures and power transmission systems. The aim of this module is to equip the learner with the knowledge, analytical skills and professional attitude needed identify, calculate, and interpret stresses in simple mechanical structures and components.
Simple Stress and Strain
Tensile and Compressive Stress and Strain in rods/hangers.
Modulus of Elasticity, Modulus of Rigidity, Poisson’s Ratio.
Stress and Strain in composite bars, Thermal stress and strain.
Shearing Force and Bending Moment
Definition and sign convention.
Derivation of relationship between intensity of loading, Shearing Force and Bending Moment.
Graphical construction of Shearing Force and Bending Moments Diagrams
Bending Stress
Bending Stress: Pure bending.
Assumptions of simple theory of bending
Derivation of bending equation.
Application of bending equation to beams, shafts, and pipes.
Moments of Area
Using First moment of Area to find neutral axis
Parallel axis Theorem
Second Moment of Area of complex symmetrical and unsymmetrical sections.
Combined Bending and Direct Stress
Eccentric loading of a short column or pipe bracket.
Torsion Equation
Derivation of Torsion equation.
Calculating shaft diameter to transmit a given power.
Calculating maximum shear stress in a shaft
Shafts in series and parallel.
Composite shafts
Thin Cylinders
Stress and strain in thin cylinders and thin spherical shells.
Change in volume due to internal pressure.
Stress in ducting sections
Review of Basic Concepts of Dynamics
Force, energy and momentum.
Differential equations of motion.
Rotational motion and centrifugal forces.
Equivalent Dynamic Systems
Application to lifts and hoists.
Application to fans/pumps.
Friction and Power Transmission
Friction in screw threads, applied to jacks and bolts.
Flat plate, cone and centrifugal clutches, uniform pressure and uniform wear.
Belt drives, transmission of power through vee-belt, centrifugal tension.
Vibrations
Free vibrations
Simple harmonic motion.
