ENAS302
Continuum Mechanics
Syllabus
- Load on Structure and Response of Material (1 hour)
- General load on structure and its effects
- Elastic and non-elastic response of solids
- Isotropy, anisotropy, continuity and homogeneity
- Effect of temperature on elastic and plastic range of solids
- Stress Tensor (4 hours)
- Definition
- Stress at a point
- Stresses on structure due to general load
- Stress notation and sign convention
- Stresses acting on arbitrary planes
- Transformation of stress and principal stress
- Stress on deformable body: differential equations in rectangular and polar coordinate systems and their application and solution
- Case study of applications in aerospace engineering
- Deformation on Body and Strain Tensor (3 hours)
- Definition of deformation on body and strain tensor
- Strain at a point
- Strain on structure due to general load
- Strain notation and sign convention
- Strain acting on arbitrary planes
- Transformation of strain and principal strain
- Small displacement theory
- Volumetric strain
- Case study of applications in aerospace engineering
- General Hooke's Law (2 hours)
- Definition of general Hooke's law
- Internal energy density, strain energy and complimentary strain energy density
- Anisotropic and isotropic elasticity
- Equation of thermo elasticity for isotropic materials
- Statically Determinate and Indeterminate Structures (4 hours)
- Introduction to energy method
- Work done in deflection, reciprocity theorem
- Strain energy for various types of loading
- Castigliano's theorem
- Use of a fictitious load, unit or dummy load method
- Curved Beams (4 hours)
- Definition of curved beam
- Circumferential stress in curved beams
- Radial stress in curved beams
- Deflection of curved beams
- Bending of Thin Plates (4 hours)
- Pure bending of thin plates
- Plates subjected to bending and twisting
- Plates subjected to a distributed transverse load
- Combined bending and in-plane loading of a thin rectangular plate
- Bending of thin plates having small initial curvature
- Energy method for the bending of thin plates
- Torsion (4 hours)
- Definition of torsion
- Torsion of non-circular solid section
- Saint-Venant's semi-inverse method
- Torsion of a narrow rectangular cross section
- Torsion of hollow thin wall section
- Shear Centers for Thin Wall Beam Cross Section (2 hours)
- Shear flow in thin wall beam cross section
- Shear center definition and formulation for channel section
- Composite beams
- Application in aerospace design
- Structural Instabilities of Thin Plates and Beams (2 hours)
- Buckling of thin plate
- Local instabilities
Practicals
- Find the shear center of a given section and compare with the theoretical value
- Compare measured deflections of various curved members with values calculated by exact and approximate methods
- Investigate the effect of different notch depths on the energy absorbing characteristics of metal materials at room temperature using the Charpy impact method
- Inspect the helicopter and identify the mechanical stability
- Determine the torsional strength of solid shaft and compare with theoretical value
Evaluation
- Chapters 1 and 2 (5 hours): 10 marks
- Chapters 3 and 4 (5 hours): 10 marks
- Chapters 5 and 6 (8 hours): 16 marks
- Chapters 7 and 8 (8 hours): 16 marks
- Chapters 9 and 10 (4 hours): 8 marks