Monday, 29 April 2013
Monday, 22 April 2013
For a change, here is some art that is not on the internet or in a gallery. It's on the wall in my step-uncle's playing-about-on-t'internet room. He inherited it from his step-dad, who ran a pub on the harbour front in Ramsgate, and had accepted it as payment for a bar tab. The artist, Paul Teschinsky, is thought to be a German Jew who came to Ramsgate just before the Second World War.
A quick search on the google showed that his favourite subject during the First World War had been German warships and submarines. Many were of a patriotic nature, perhaps approaching propaganda; some illustrated post cards issued by the German army postal service. Ironically, the ever present enemy alluded to in these painting would later give him refuge from his own country: paintings were titled 'War against England stormy day in the North Sea', 'German submarines off the coast of England', and 'The turbine cruiser Dresden chasing the English steamer Mauretania'.
Labels: Wave art
Monday, 15 April 2013
Ya cannae get aroond conservation o' energy, ya reekie oxtered sassenachs yae. (Translation from the Scots: You can't get around conservation of energy).
Conservation of energy from a far field perspective
Consider an arbitrary boundary around a big bit of sea. In order for a wave energy converter (WEC) to absorb energy from within that boundary, the waves leaving the boundary must have less energy than the waves entering the boundary. The only mechanism to capture useful energy while ensuring less energy in the waves leaving the boundary, is to create waves that destructively interfere with waves that would leave the system in the absence of energy capture. To create waves while absorbing energy involves the radiation of waves by damped (by a power take off system that is) wave excited motion.
Monday, 8 April 2013
Many commentators have pointed out that locations with low average wave power tend to have a smaller ratio between average and extreme wave powers. This ratio between average and extreme wave powers is one of the underlying challenges of extracting wave energy. This suggests that lower energy sites could give cheaper wave energy.
Monday, 1 April 2013
An understanding of the importance of large industrial partners to the wave energy industry can give important insights into some of the challenges currently facing wave energy. The main reason large industrial partners are essential is that demonstration projects typically have large capital and operating costs.