Evans Water Engineers

EVANS ENGINEERING

TRECARRELL MILL · TREBULLETT · LAUNCESTON · CORNWALL · UK · PL15 9QE
+44 1566 782285 · www.evans-engineering.co.uk · email sales@evans-engineering.co.uk

“The Student Corner”

The study of water in its many forms and uses is a fascinating subject that I have been engaged in since I was a small boy. I often joke that it came as a shock to me to learn that not everyone generated electricity from a shed at the bottom of the garden. The growing concern about climate change, dependence on dwindling fossil fuel reserves and the growing populations demand for water, has rightly lead to students and possibly their teachers, taking a more enlightened look at how we use and preserve our water resources.

In this page I will outline some of the areas that interest me and may interest you, or may be relevant to a project that you are doing. There will no doubt be many additions and alterations, so I would be delighted to hear about your projects, the kind of information you are looking for and if you have found something that you think others would be interested in (or laugh at!) please send it in. If there is enough interest I may start a dreaded ‘blog thing’. I will be adding specific links in this area of the site, so do come back more than once and see how it is going.

When people are being steered towards more computer simulation and illustration, I would like to make the case for getting muddy! There is no substitute in my opinion to making dams in streams with stones and lumps of mud. As a boy my father made me a set of canal lock gates so that I could move my model boat from one muddy puddle to another, and I am sure that I had a lasting impact on me because although the puddle is long gone, it lies directly beneath the hydro plant that now powers my workshop. Pictured to the left with my daughter Amy, I am trying out a working model of a horizontal shaft ‘Darrius’ turbine that we built for IT.Power, many years ago. Peter Frankael has gone on to design ‘Seagen’ the tidal current generator, and Amy is helping to fight legal battles to safeguard the planet.

PRIMARY SCHOOL PROJECTS

The construction of simple waterwheels and turbines from household items and waste products can make interesting and rewarding DT projects. A competition to make the most ingenious device to raise water or generate power can be a rewarding project. Interesting and messy outcomes are all part of the hands-on approach!

GCSE GEOGRAPHY & DESIGN TECHNOLOGY

Slightly more structured projects that convert the potential energy from a tank of water or the laboratory tap into small amounts of electricity using a ‘permanent magnet’ generator (salvaged from a wind-up or hand-operated torch) to light a few LEDs, will make a good exhibit for that school open-day. Water-engineering is one of the few disciplines where the raw material is all around us, but few even at a high academic level have ‘a hands-on feel for the ‘material’ itself. I have even heard university professors misunderstand ‘Wave Energy’ and ‘Tidal Energy’ and to disbelieve that you can increase the output of an ‘Impulse Turbine’ with vacuum from a draft tube!

UNIVERSITY DISSERTATION or PROJECT

There are many very interesting areas for projects and original research in the water-engineering field, but I have a word of caution. It is very easy to propose a project on for example, ‘a design for a turbine for use in developing countries’ but it is quite something else to deliver. These are two quite distinct areas, to design a turbine that works and to adapt or tailor a technology so that it is suitable for use in remote areas or areas where there is little or no technical backup. There have been ‘apprentice projects’ from high profile engineering companies that were totally inappropriate to third world use simply because nobody understood how difficult it is to look after equipment in the West, let alone several days walk from the nearest road.

COLLABORATIVE RESEARCH & DEVELOPMENT

Something like 40% of all funded government funded R&D projects in the EU cover work that has already been done, and often to a higher standard than is in the proposal. This is particularly true of the ‘staple engineering subjects’ rather than ‘cutting edge technologies’. The reason for this duplication is partly the lack of historical knowledge but also the need for academic institutions to do something to get funding, even if it is ‘old hat’! Numerous projects in the water turbine sector literally start by trying to ‘reinvent the wheel’ instead or spending a few days in background research at the various patent libraries.

There are over 100 different types of water turbine that have been designed and tested over the years, but reading most modern technical books and papers on the subject you would be lead into believing that there were only half a dozen. In fact it is a complete spectrum of designs where particular academics or manufacturers have concentrated on parameters such as efficiency, ease of manufacture, specific speed or flow regulation, and their degree of success has been very varied. Over time, areas that once caused problems such as speed regulation have been overcome, opening up new prospects for turbine designs once abandoned.

RELEVANT TRAINING PRODUCTS

We have built a range of items from simple demonstration models to fully working test rigs for education and the London Science Museum. In the future we will be offering educational material covering the wider issues about water, as well as project material for waterpower study.