Today Brenton and I went out on a little mountain bike ride in Mac Forest. We rode from in town out Highland Drive, up Crescent Valley Road, and then up to the Jackson Creek parking area. From there, we took one of the 600 roads up and around to Upper Horse trail, onto another road, and up onto the 650 and the top of Dimple Hill. On the way back we bombed down Dan’s Trail and tied into the Timber Hill housing project to get back into town. In total the ride was around 16 miles of muddy fun.
Combined Brayton – Rankine Cycle Analysis
Brenton and I wrote up a little report for our advanced power generation systems class with Dr. Peterson. He asked us to analyze a combined brayton/rankine cycle power plant and find the optimum configuration with a few parameters set. After futzing around with the code in Engineering Equation Solver, otherwise known as EES, we got a working model. Then we went a little crazy.
Instead of probing around manually using EES, we found that there was a wrapper to interface between EES and Model Center, a piece of software that is designed to explore trade spaces and can also find optimal designs on the side. Predictably, OSU had purchased the “commercial” version of EES rather than the “professional” version. This caused us some headaches because the “commercial” version is crippled. It will not accept command-line prompts which the wrapper for model center relies on.
Some quick thinking found a program called AutoHotkey that can inject keystrokes and mouse clicks into any program. A small script and some editing of the wrapper file, and we were in business. Albeit, it was a slow bit of business. Rather than running a few hundred iterations of the model in a few minutes, we could only run one per ten seconds because of the troublesome graphical interface that insisted on loading with EES every time the model ran.
After about a day of non-stop simulating with one of us babysitting the computer for the periodic crap out and explosion of EES, we had good data. All points indicated a convergence at one point. It was actually pretty darn efficient. We slapped the results and methods into a report and shoved it underneath Dr. Peterson’s door at about 2am the morning it was due.
The report is available in Microsoft Word format. Eventually I might put it on the site directly but for now, it’s an attachment only.
Changing fork oil and seals
Replaced fork seals and cleaned out fork internals. Carl helped. Brenton let us use the SAE shop to do the work. The left fork was rusted and corroded inside. We cleaned both forks out and flushed them with new oil. The manual had an error in it that led us to reassemble the forks incorrectly. They were too raked out which made it impossible to reassemble the bike and also caused there to be no damping. We had to come back the following day to finish the job as we had been in the shop from 6pm to almost 2am. The following day, we were able to completely disassemble and reassemble the forks and put them back on the bike in only a couple of hours.