Technology Project Class 12

Today we had to present stage 3 of our project. When we entered class there was only 6 of us. Jal and I were the only group that was there and me and him were not keen on presenting first so we had to wait for about half an hour before finally someone decided to present first. For the first time Simon and Vadim were not the first to present their work which makes me feel a bit better.

Also this time I was really happy with our progress in the technology project. There was plenty to present with the practical testing that we had done. I was really happy with what he had presented after we had finished as I believed that we had made some really good progress over the other groups that had presented.

At the end of the presentation Anura questioned us as to whether or not we thought the project was viable or not. I immediately said no as the highest pressure achieved was 0.5 psi. And most exhaust brakes operate at around 30 - 60 psi. For this reason I said no. Anura then said we should calculate backwards and workout whether that pressure achieved would actually slow the piston down or not. This is a good idea and it would be good to see what becomes of these calculations. I still believe however after our practical testing that the exhaust brake on small diesel engines is going to be unviable. Considering the cost of the unit compared to what it can achieve for engine braking in diesel engines.

Technology Project Class 11

Today there was no official class for technology project. However Jal and I still went into uni as today finally the technician had put in the valve on the Mercedes common rail diesel engine. So is that we could get some pressure readings done for the exhaust system in the engine and see how it works and how the exhaust brake may affect these readings.

First we did tests at varying RPM's to get different pressure readings across the rev range without an exhaust brake. Then we did tests with the exhaust brake applied all the time and noticed a large increase in exhaust pressure on the manometer. Finally we did tests with the exhaust brake applied at engine overrun conditions and noticed the largest pressure readings which is good to see our projects concept actually works.

Technology Project Class 10

Today we had our second stage presentation on our progress on our technology project the retro fit exhaust brake. Once again I feel as if we have not achieved enough and that we are not making particularly good progress. And once again Simon and Vadim presented their project first. In comparison to their progress we have done nothing. I am hoping to some progress this week.

On thursday we met with our technical advisor, Anura and he said to use that we should do a hardness test on the exhaust brake butterfly valve and shaft which were he had kindly sourced and supplied to us for free. So we went to see Jone the materials lecturer who did not know how to use the hardness tester. So he told us to see Anura who wound up knowing how to use and showed us. He told us about the different hardness testing ways which go from hardness rockwell A through to hardness rockwell G.

The next part really interested me, Anura was able to get one of the technicians to fit a valve in the back of the exhaust pipe behind the turbo so is that we could use a manometer to measure the pressure behind the turbo. So I am hoping that the technician can do this so we can get some more practical testing done, rather than all our work being theoretical.