Thermo Scientific DCT6088, User Manual

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Chapter 1
Product Overview
The Thermo Scientific DCT6088 dedicated transit time flowmeter is a
microprocessor-based instrument that measures the flow of clean,
homogeneous liquids (liquids without large concentrations of suspended
particles or gasses such as air bubbles). The flowmeter is non-invasive,
which means that it measures flow from outside the pipe. The transducers
can be mounted to a pipe within a matter of minutes, and flow
measurements may be made without interrupting the flow or modifying
pipe work. The instrument can be configured using an integral keypad for
entering variables such as pipe size, pipe material, wall thickness, and fluid
type.
Introduction
Theory of
Operation
Sound waves travel in fluids at a specific velocity depending on the type of
fluid. If the fluid is moving, the sound wave travels at a velocity equal to
the sum of the speed of sound in the fluid and the velocity of the fluid itself
relative to the transducer. A sound wave traveling in the same direction as
the fluid flow (downstream) will arrive sooner than a sound wave traveling
against the flow (upstream). A transit time flowmeter operates by
measuring both the absolute travel time of each sound wave and the
difference in time required for the waves to travel between externally
mounted downstream and upstream transducers (refer to Figure 1–1).
Based on the transit time of the two sound waves, the flowmeter calculates
the average fluid velocity.
Figure 1–1. Typical transit time system
Thermo Fisher Scientific DCT6088 User Guide 1-1