a water distribution network is subjected to various abnormal conditions such as pipe breaks, pump failures, excessive demands etc. in the design period. under such conditions, the network may not be able to meet required demands at desired pressures, and becomes deficient. traditional network analysis assumes nodal demands to be satisfied and available nodal pressures are calculated. however, ...

Breivoll Inspection Technologies (BIT) has successfully developed and implemented a new in-pipe inspection method for the condition assessment of metallic water mains, mainly cast iron. The method is based on Acoustic Resonance Technology (ART). The inspection data (acoustic signals) are stored on a hard drive prior to undertaking the detailed analysis back at the office. The assessment results...

By combining total internal reflection fluorescence cross-correlation spectroscopy with Brownian dynamics simulations, we were able to measure the hydrodynamic boundary condition of water flowing over a smooth solid surface with exceptional accuracy. We analyzed the flow of aqueous electrolytes over glass coated with a layer of poly(dimethylsiloxane) (advancing contact angle Θ = 108°) or perflu...

The Bernoulli boundary condition for traveling water waves is obtained from Euler’s equation for inviscid flow by employing two key reductions: (i) the traveling wave assumption, (ii) the introduction of a velocity potential. Depending on the order of these reductions, the Bernoulli boundary condition may or may not contain an arbitrary constant. This note shows the equivalence of the two formu...

The goal of this paper is to derive in the two-dimensional case necessary and sufficient minimality conditions in terms of the second variation for the functional v 7→ ∫ Ω ( |∇v| + χ{v>0}Q ) dx, introduced in a classical paper of Alt and Caffarelli. For a special choice of Q this includes water waves. The second variation is obtained by computing the second derivative of the functional along su...

This work proposes a method for prioritising critical water mains (CWMs) with high risk, in terms of both failure probability and consequence costs. The proposed method can improve the prioritisation of high-risk CWMs requiring condition assessment in the near future and will further optimise the operational maintenance of water utilities. Due to the improved prioritisation, water utilities can...

Effects of water on the catalytic performances of MoVTeNbO catalyst in the oxidation of propane to acrylic acid have been investigated at different reaction temperatures and different steam contents. Obtained results show that both catalytic performances and catalyst structure are very sensitive to the presence of water vapor in the reaction feed. Presence of water induces some structural modif...