Manual – Starflow Ultrasonic Doppler Instrument
Model 6526
Unidata Manual - 6526 Starflow User Manual Issue 17 01 2020.docx
Page 61
Creating an Area Rating Table
To calculate Flow, Starflow uses a lookup table called the Area Rating Table. The Area Rating
Table is automatically generated when the scheme is saved from information provided in the Flow
extension instrument.
An Area Rating Table is created for each scheme. This table is generated by one of three
methods depending on the Starflow site.
Type
Starflow Site
How Created
Pipe
Partially filled circular pipe Enter offset, diameter and dead sector in Area
Rating Table window.
Open Channel Open channel and natural
stream
Entering the correct dimensions in the flow
extension instrument
User Defined
Other closed-in shapes,
like an ovoid pipe
Create a text file listing measurements. Nominate
this file in the scheme’s User Rating file.
Partially Filled Pipe
There are four parameters needed to define a pipe installation.
Range (m)
Depth range of Starflow. This defines the depth range able to be measured by the
Starflow. There are two ranges: 2m and 5m although if the depth will never be above the 1m
range this should be selected for greater precision.
Define the smallest maximum depth for the channel that is compatible with your Starflow as this
will give best results. For example - For a 2m depth range Starflow in a 900mm diameter pipe
choose 1 to improve accuracy.
Offset (m)
Offset defines the offset from the bottom of the pipe to the position of the Starflow
depth sensor. This is usually zero; however, in some installations the Starflow may be located
away from the bottom (to avoid silt and rubbish).
Pipe Diameter (m)
Defines the pipe diameter.
Dead Sector (m)
The deadband due to siltation (if any).
