Thermodynamics

Thermodynamics States About Energy Conversion Thermodynamics is the branch of science that embodies the principles of energy transformation in macroscopic systems. The general restrictions which experience has shown to apply to all such transformations are known as the laws of thermodynamics. These laws are primitive; they cannot be derived from anything more basic. The first law of thermodynamics states that energy is conserved; that, although it can be altered in form and transferred from one place to another, the total quantity remains constant. Thus, the first law of thermodynamics depends on the concept of energy; but, conversely, energy is an essential thermodynamic function because it allows the first law to be formulated. This coupling is characteristic of the primitive concepts of thermodynamics. The words system and surroundings are similarly coupled. A system is taken to be any object, any quantity of matter, any region, and so on, selected for study and set apart (men...

Flange Taps As Flow Meter

Flange taps are the most widely used pressure tapping location for orifices. They are holes bored through the flanges, located one inch upstream and one inch downstream from the respective faces of the orifice plate. A typical flange tap installation is shown on the figure. The upstream and downstream sides of the orifice plate are connected to the high pressure and low pressure sides of a DP transmitter. A pressure transmitter, when installed to measure flow, can be called a flow transmitter. As in the case of level measurement, the static pressure in the pipe work could be many times higher than the differential pressure created by the orifice plate.

In order to use a capsule that is sensitive to low differential pressure, a three valve manifold has to be used to protect the DP capsule form being over-ranged. The three valve manifold is discussed in more detail in the section on level measurement.

Other type of orifice to measure of flow is corner taps. Corner taps are located right at upstream and downstream faces of the orifice plates. The figure of those flange taps and corner taps will upload in different time, as on the below picture.