First things, I'm going to Sweden in May! Woo! My paper was accepted - I was a little bit concerned that they wouldn't agree with my changes and responses, but no further feedback.
At the beginning of March was the EWB Conference in the Royal Academy of Enginnering, London. The conference was split into 2 sections, education and research. I wasn't really initially interested in the education part, I didn't care that much about it. However, I had to attend one of the talks and so went to one called "I don't want to change light-bulbs; I want to change the world!", mainly because I liked the title. However, it was very good. It talked about problem based learning, using complex questions that have no correct answer. I thought it was a very interesting way to learn, very similar to how you work. I presented in the energy panel, which also featured work from Solar, biogas, biofuel briquettes and smokeless stoves. It was great to see a broad spectrum of energy research, but all trying for the same goal. The other panel I attended was the industry panel, mainly to listen to Jon Leary and listen to the presentation about the desert fridge. The papers for them can be found here and here. It was a great day, I managed to meet a lot of people to discuss some ideas, although didn't get as much feedback on my project as I'd hoped. I stayed in London for the Saturday after the conference, Hannah came up and we went to Tower Bridge Exhibition - a fantastic exploration about how Tower Bridge works - before heading to the West End to watch The Lion King - The Musical, which was absolutely amazing.
Tower Bridge Old Engine Room
Along with Katie Cresswell-Maynard from EWB, we gave a talk to the IMechE, Bristol and Bath branch. Katie talked about the need for engineers to help in global warming and poverty alleviation. Some of the statistics really made me think. Over 1.5 billion people (around 20% of the world's population) without proper sanitation. 900 million people without access to drinking water. Then over the next 20 years our requirement for water, food and electricity are going to be increasing with population growth. It's a big issue. I think the thing that got me the most that 1.5 million people a year are dying from preventable diseases. That to me is just wrong. After all those sobering statistics, I stood up and talked about my project, the technology I'm looking at and the benefits. I think the thing that brings it home to me is some of the interviews that we carried out in Nepal with PEEDA. There, people were so grateful that they had received electricity, it enabled them to work at night-time, not have to pay for kerosine and have clean and safe lighting as well as TVs and radios. (Video taken from PEEDA's website.)
I think I gave a good talk, and I met a lot people who wanted to chat about the project and has given me some more motivation about going forward.
I've been progressing with the testing. It's been quite slow initially, trying to understand how the rig can be operated. First I looked at how to capture all the water exiting the turbine, so the water didn't go over the floor. After some searching, I found a huge tank in the back of the Hydrolab, which could sit the turbine rig in. Any splashing water would then be captured by the tank, and pumped out by the submersible pump.
The rig in the large tank
The next task was to test the jet to ensure it was stable and a constant diameter. As can be seen in the photo below, the jet looked good across all heads.
The jet stability
With the jet stable, I did a check to see how much the head could be varied. From my specification, the head needed to be able to vary between 0.5m and 3.5m head. The head is adjusted by using two valves in the pipe run, one controlling the main head, then the second takes off any excess water, reducing the pressure. The flow is measured to calculate the head at the nozzle using velocity head. We could vary the head down to 1.0m, but below that, the flow rate became too low and the flow meter was unable to measure it. However, it was decided that this was not a real problem. We increased the head to maximum to see what it would be. However, as the static pressure increased behind the nozzle, this became too much for it and blew the nozzle off the pipe. Then followed a scene similar to those in slapstick films where I attempted to hold on to a flailing hose which was intent on covering the Hydrolab with water. After that I fixed the nozzle in with glue and put two grub screws in to fix it onto the pipe, which would increase the strength of the joint. I also resolved to only push it as far as 3.5m head!
Once this was done, the the testing began. Being a aero/mechanical engineer, I have never really used oscilloscopes before, so it took me a while, and a lot of help (thanks Niall and Gyorgy) to learn how to use it properly. However, once this was overcome, then I managed to get some readings for torque and speed out of the turbine. I was able to do a couple of runs at a constant head, varying the speed of the turbine as well, by varying the electrical load on it. From this I've got some initial curves which I need to now compare with my model.
The modelling has been more tricky than I had initially imagined. The flow inside the Turgo turbine is highly complex, with a jet impinging on the Turgo cups. There are several different forces at play, 3D flow effects and factors due to the shape of the cups and angle which the jet impacts it. All of which means that the next step from a simple 2D model is highly complex, and would normally include some sort of CFD. However, I have no intention of doing any CFD as this would not allow the model to be simply run for lots of different cases easily. Also, the CFD model would be severely complex as well. So, I've been reading up on how Pelton wheels are modelled to see if I can use any of the techniques there to match with the Turgo.
Outside of the PhD, I have been doing some more work with HTC. In the last week of February they did a evening of songs from the shows, films and TV. There was minimal stage management work to do on this occasion, so instead I found myself sat behind the sound desk. There, I had to balance the sound of the show between the backing tracks and the singers. I had never done anything like it before and found it very difficult to do, however, by the end of the run I found myself getting better. The show was a great success and we managed to have a full house most nights.
At the beginning of March I was very tired. I decided that I needed a short break, and so spent a week in Scotland visiting some friends and my cousin. I went to Aviemore, where a friend works in an outdoors shop. There I went for a bit of a wander around and climbed a hill behind the town. From Aviemore, I drove over the Cairngorms, by the slightly dubious ski centre at Lecht, and headed to the granite city of Aberdeen to stay with my cousin Linda, and her husband Dave. I had a brilliant time with them, just relaxing, reading, watching films and talking. I was amazed at the length of Aberdeen's beach, which stretched several miles up the coast. Hundreds of miles out to sea from Aberdeen are the oil and gas rigs, making Aberdeen Europe's self proclaimed 'energy capital'. Although you can't see the rigs themselves, you do know they are there. Very regularly, helicopters fly overhead ferrying workers to and from the rigs. In the bay by Aberdeen several supply ships are sat, waiting for their next delivery. It was quite fun just to sit and watch the world go by.
A view from the hill behind Aviemore
In Aberdeen, I also met a friend of mine from my undergraduate days, Keith. Keith was a engineer on the helicopters, doing the maintenance. As he did shift work, I was lucky enough to see him for a couple of days and we headed into the mountains again to have a look at the Victorian trail - around 60 miles from Aberdeen is Balmoral, the Queen's summer residence. As we headed deeper into the Cairngorms, the weather closed in around us, and then the snow came. It was fun to be driving in the snow again (or to be exact, driven in the snow), but I wasn't looking forward to making my way back to Aviemore again in it. So, when the time came to head back, I went the long way round, avoiding all possible snow related problems. Phew. One relieved Sam.
The snow falling as we head along the Victorian Trail up the river Dee
The next month sees me doing more testing and hopefully getting further along the road with my model. I need to start working on the next phase of the project as well soon, looking at the electrical side of things. Hopefully that can start more in earnest soon too!
SAM
p.s. This is a picture of Aviemore station, which has always been somewhere I've wanted to go. When we were little, we used to play a game called The Great Game of Britain, where you would get sent to Aviemore station and could normally only leave if you rolled a six...
Aviemore Station! My life is now complete...
