Manhole Flow Deconvolution

NEWS-The Manhole Flow Deconvolution team has completed their project report. Copies can be requested by contacting the page owner or the School of Engineering.

Issues of climate change are placing increasing pressures on engineers to prevent flooding and requires them to design sustainable and economic urban drainage systems. This has resulted in a requirement to increase our understanding of the effects of surcharges, discharges and retention times of drainage systems and structures.

Drainage needs to be considered from the outset of any scheme from major highway projects to residential driveways and incorporated into the design at an early stage. These systems can take many different forms but all have the basic function to convey water and effluent from source to outflow. Conveyance is complicated by the many obstacles and processes in the system. Studying the effect of drainage structures on flow conditions, transport and dispersion of soluble material is therefore very important. Changes in a drainage systemâ€™s cross-sectional shape across drainage structures influences solute travel time and mixing in the fluid. A good example of this, and probably the most common feature in a traditional drainage system is a manhole.

The project seeks to utilise an existing Matlabâ„¢ algorithm developed in a PhD thesis by John Hattersley. The algorithm uses a mathematical deconvoultion technique to analyse the processes taking place in a system based on its inputs and outputs. We aim to develop this technique to model and determine output flows in manholes and other drainage structures. This will be achieved through trials on existing data sets and by conducting experiments on a model manhole using fluorescent tracer dyes. If the algorithm provides positive results; a manual will be created detailing the theory it is based on, how to use it, as well as its limitations. Various flow types will be tested such as pulse and step flows in order to determine the limitations of the algorithm.

Project Aims:

1. Testing the current MatLab algorithm to observe how accurate it predicts the output concentration.

2. Understanding the algorithm and determining its limitations.

3. Design a Graphical User Interface and complete a manual on what the program does and how it operates.

4. Using our own experimental data, using a scaled manhole model, for steady and pulsed flows to test the accuracy of the model.