Dundee Tunnel Research

Ultrasonic Anemometer Data - Southbound

This page contains data measured using ultrasonic anemometers during the following Southbound train runs:

Train Run Number Speed (km/h) Data File
35334 157.5 35334-s02.dat
35338 163.5 35338-s05.dat
35340 202.0 35340-s07.dat
35352 202.0 35352-s12.dat
35358 198 35358-s14.dat
35362 197.5 35362-s17.dat

The data files can be viewed in a text editor and can be downloaded from http://www.thermotun.com/airshaft/ultrasonic/ultrasonic-southbound-dat.zip



Example Graphs

The following example graphs have been produced from data file 35334-s02.dat

The measurement enclosure on top of the airshaft was divided into 8 compartments (see photographs of the airshaft). The layout of the graphs represents the distribution of 6 ultrasonic anemometers in the airshaft as viewed from above.

Each ultrasonic sensor measured flow data in 3 directions. Each direction is shown in a different set of graphs below. The speed of sound was estimated by the ultrasonic sensors and is included in a further set of graphs.

Ultrasonic sensor orientation
Diagram of airshaft from above showing orientation of ultrasonic sensors.

u direction: vertical airflow component (+ve = up the shaft)


v direction: lateral airflow component (+ve = right to left in the top boxes, left to tight in the bottom boxes)


w direction: longitudinal airflow component (+ve = inwards from shaft wall)


c: speed of sound (approx)


u direction: Comparison between two sets of three ultrasonic sensors.