Sunday, 12 June 2016


A cooling tower is a heat rejection device which rejects waste heat to the atmosphere through the cooling of a water stream to a lower temperature. Cooling towers may either use the evaporation of water to remove process heat and cool the working fluid to near the wet-bulb air temperature or, in the case of closed circuit dry cooling towers, rely solely on air to cool the working fluid to near the dry-bulb air temperature.
Common applications include cooling the circulating water used in oil refineriespetrochemical and other chemical plantsthermal power stations and HVAC systems for cooling buildings. The classification is based on the type of air induction into the tower: the main types of cooling towers are natural draft and induced draft cooling towers.
Cooling towers vary in size from small roof-top units to very large hyperboloid structures (as in the adjacent image) that can be up to 200 metres (660 ft) tall and 100 metres (330 ft) in diameter, or rectangular structures that can be over 40 metres (130 ft) tall and 80 metres (260 ft) long. The hyperboloid cooling towers are often associated with nuclear power plants,[1] although they are also used in some coal-fired plants and to some extent in some large chemical and other industrial plants. Although these large towers are very prominent, the vast majority of cooling towers are much smaller, including many units installed on or near buildings to discharge heat from air conditioning.

Saturday, 11 June 2016



Finite Element Analysis (FEA) is a computer-based numerical technique for calculating the
strength and behaviour of engineering structures. It can be used to calculate deflection, stress,

vibration, buckling behaviour and many other phenomena. It also can be used to analyze either
small or large-scale deflection under loading or applied displacement. It uses a numerical
technique called the finite element method (FEM). 
In finite element method, the actual continuum is represented by the finite elements. These
elements are considered to be joined at specified joints called nodes or nodal points. As the
actual variation of the field variable (like displacement, temperature and pressure or velocity)
inside the continuum is not known, the variation of the field variable inside a finite element is
approximated by a simple function. The approximating functions are also called as interpolation
models and are defined in terms of field variable at the nodes. When the equilibrium equations
for the whole continuum are known, the unknowns will be the nodal values of the field variable.