The intended use of the Tow Tank Seeder System is to deposit hollow glass spheres, approx. 10-micron diameter into a water test tank. It is designed to be mounted at a suitable location on the carriage so that it can seed a small area around the vessel and thus minimise contamination of the tank, thus also minimising the quantity of particles used. The carriage then traverses over the length of the tank with the seeder immersed at the required depth.
Once the seeding has been deposited, the seeder is retraced from the water and the carriage commences the measurement run. Flow measurements are not carried out during the seeding phase but shortly afterwards as the seeder will produce undesirable flow disturbance in the water which will adversely affect the flow measurements. The particles are nearly neutrally buoyant and they remain in the water for a generous amount of time to carry out several flow measurement passes
By design the seeder is retractable so that it can be permanently installed on the carriage. It can also be easily removed when not in use. Deployment and retraction is easily facilitated by an electrically operated winch.
The basic components of the SCITEK Tow Tank seeder are shown in the schematic diagram shown above. It comprises of the rake which is essentially five rows of metal tubes with multiple holes drilled into the wall of each tube which are used to discharge water that is premixed with hollow glass spheres. The rake is designed to spread the seeding evenly in the area of interest.