Fig.1. A typical cable-membrane structure The following assumptions are made in this example: Cables are discretized using LINK10 elements. The membrane is discretized using triangular SHELL41 elements with 'cloth' feature turned on. No slip between cables and membrane. The material complies with Hooke’s Law. The material is orthotropic and elastic. The two principal axes of … Continue reading Nonlinear analysis of a cable-membrane structure: from shape-finding to static and modal analysis
Structural Engineering
Torsional limit analysis of a container
Fig.1. A typical container This problem is to analyze the torsional limit of an open container (without lid). It is a typical problem in structural nonlinear buckling analysis. As an alternative to the Newton-Raphson method, the arc-length method will be used. Fig.2. A simplified model of the container body Some assumptions and simplifications in this … Continue reading Torsional limit analysis of a container
Wear analysis of casing coupling
Fig.1. Typical casing couplings Because the reciprocating and rotary motion of the drill pipe in the casing is eccentric, the radial and axial friction between the drill pipe and the casing causes serious wear on the outer surface of the drill pipe and the inner surface of the casing. This wear mostly occurs at the … Continue reading Wear analysis of casing coupling
The Analysis of Piston Rubber Film of Pneumatic Brake Device
Fig.1. Typical piston rubber films (with central hole) Fig.2. A typical piston rubber film Fig.3. A typical piston rubber film (edge can be fixed with bolts) Typical piston rubber films in a pneumatic brake device that is commonly used in drilling operations are shown in Fig.1-Fig.3. When the brake device is activated, the piston rubber … Continue reading The Analysis of Piston Rubber Film of Pneumatic Brake Device
The stress-strain curve of rubber material stiffened by carbon fiber
Fig.1. Illustration of the discretization and BCs A 2D model is created. Plane elements and beam elements are used to discretize rubber material and carbon fiber, respectively. To ensure that rubber and carbon fiber deform together (no slipping), plane elements and beam elements share common nodes. A concentrated force (the red arrow in Fig.1) is … Continue reading The stress-strain curve of rubber material stiffened by carbon fiber
The stress analysis of curved casing
The outer diameter of the casing is 177.8mm, and the thickness of the casing is 13.72mm. The steel grade of the casing is N80. The yield strength is 551.6MPa. Poisson's ratio is 0.3. The elastic modulus is 2.06GPa. The curvature of the casing is 6degrees/100m. Perform 3D analysis using SOLID95 elements. FINISH /CLEAR !***************************** !units: … Continue reading The stress analysis of curved casing
The stress analysis of eccentric-wear casing
Fig. 1. As shown in Fig.1, the outer ring is the casing, and the middle is the drill pipe. The unworn part of the casing is going to be analyzed. The diameter of the drill pipe is 127mm. the outer diameter of the casing is 177.8mm, and the thickness of the casing is 13.72mm. The … Continue reading The stress analysis of eccentric-wear casing