Potentiality of a velocity profiler to investigate sewers

Potentiality of a velocity profiler to investigate sewers: Results of laboratory experiments

Cedillo Galarza, J.S.

Clemens, F.H.L.R. (mentor)
Luxenburg, W. (mentor)
Lepot, M.J. (mentor)

Civil Engineering and Geosciences

Water Management

2016-08-15

In order to propose a new sewer inspection method, a velocity/turbidity profiler (Ubertone, UB Flow F-315) has been tested in a laboratory. A 50 m glass flume has been adapted with several lateral connections (with a range of diameters, angles, intrusions, cracks), supplied by a 1 m3 tank. Placed just below the free surface on a rotating (to scan the wet section) and translating (along the main axes of the flume) structure, velocity profiles have been recorded and accurately positioned along the reach (with data from three laser distance meters and a 3 Mpix camera): a 3D cloud of raw velocities is created. After raw data pretreatment (deduction of translation velocity, Nyquist jumps correction), a five step-interpolation (adapted from [16]) method has been implemented and tested: i) data filtering, ii) transformation to flume coordinates velocities, iii) isotropic gridding, iv) anisotropic gridding and v) continuity correction. In order to perform the last step, two resolution schemes have been tested: staggered and non-staggered grid. With external CFD data, the first one shows its superiority (stability) on the second one and provide consistent results to data obtained from commercial CFD software. Despite the UB Flow provides good average data, its design and instantaneous velocities make it no suitable yet for field application.

sewer systems
staggered grid
non-staggered grid
finite difference stability
Navier-Stokes equations
validation with CFD data

http://resolver.tudelft.nl/uuid:dee8f5d8-711e-4992-b45b-9734cb054038

Student theses

master thesis

(c) 2016 Cedillo Galarza, J.S.