Francois Clemens

Bio: Francois Clemens is an academic researcher from Delft University of Technology. The author has contributed to research in topics: Sanitary sewer & Combined sewer. The author has an hindex of 23, co-authored 170 publications receiving 2032 citations. Previous affiliations of Francois Clemens include Norwegian University of Science and Technology & City University of New York.

Monitoring and characterising the solids loading dynamics to drainage systems via gully pots

Abstract: Runoff (re)mobilises solids and their associated pollutants from streets and transports them via gully pots to the drainage system. As the solids negatively impact the performance of the drainage s...

Performance Indicators for Complex Wastewater Pumping Stations and Pressure Main

Abstract: With increasing energy costs, concern on CO2 emission and growing interest in asset management, the online evaluation of pressurized wastewater systems provides an opportunity for optimizing performance. This paper describes a method that uses performance indicators (PIs) derived from monitoring data and model simulation results using an online system. Malfunctioning, or underperformance can be detected in an early stage, which enables to take measures in terms of replacement or reparation based on the actual status of the system rather than rely on the effectiveness of regular, scheduled, inspection. The city of Almere's wastewater transport system is used as a case study and demonstrates the introduction, application and interpretation of these PIs as well as the obtainable reduction in energy consumption using on-line data on the systems behaviour.

Evaluation of a Method for the Design of Monitoring Networks in Urban Drainage

Abstract: When designing a measuring network several questions must be answered. Basic properties like defining sampling interval and the exact locations for measuring sites are mostly based upon expert's judgement. In this paper a design method for measuring networks aiming at obtaining information for model calibration is proposed. This method is based upon the application of a hydrodynamic model for initial design. Based on a min-max approach for the sampling frequency, a first estimate is obtained. Based on a mathematical analysis of the model parameterization and information content of potential measuring locations it is possible to judge measuring networks objectively. Moreover, by applying some optimization technique (e.g. a genetic algorithm) an automated optimization of the measuring network is possible. The method was applied to design a monitoring network in the drainage system of Loenen. During the second half of 2001 measuring data were obtained allowing for an evaluation of the design method.

Climate Change 2007: The Physical Science Basis.

Abstract: Cause, conseguenze e strategie di mitigazione Proponiamo il primo di una serie di articoli in cui affronteremo l’attuale problema dei mutamenti climatici. Presentiamo il documento redatto, votato e pubblicato dall’Ipcc - Comitato intergovernativo sui cambiamenti climatici - che illustra la sintesi delle ricerche svolte su questo tema rilevante.

Boundary Layer Theory

Abstract: The boundary layer equations for plane, incompressible, and steady flow are $$\matrix{ {u{{\partial u} \over {\partial x}} + v{{\partial u} \over {\partial y}} = - {1 \over \varrho }{{\partial p} \over {\partial x}} + v{{{\partial ^2}u} \over {\partial {y^2}}},} \cr {0 = {{\partial p} \over {\partial y}},} \cr {{{\partial u} \over {\partial x}} + {{\partial v} \over {\partial y}} = 0.} \cr }$$