Engine Preperation
Preparing an engine for testing is a design project of its own. It took us about a month to fully mount the engine on the test stand. The most significant challange was the fact that the engine needed to be mounted on its side. This because the dynamometer would only run vertically. The mounting plate for the engine had to be designed to support the engine as a cantilever. This plate was made from half inch steel with the engine mounting bolt pattern and exhaust flange CNC milled out of the plate.
Because the engine was turned on its side the oil reservoir and vapor separator had to be removed and remounted vertically. This was done by welding square tubing to the engine stand and bolting the componants so that they would function properly. Because the thermal reactors occupied the space directly behind the engine, the drive shaft had to remain at full length. The long drive shaft was supported by two pillowblock bearings to minimize dynomometer wobble. The drive shafts were turned down on the CNC lathe so that it could be mounted to the dynomometer. Unfortunantly the drive shaft was bent during this turning process. The drive shaft was partially hardened and while the hardened metal was being removed the shaft was bent. We carefully turned down another drive shaft which was not bent.
The final setup for the engine stand was the electrical system and stand alone cooling system. Once we were given the plumbing and wiring diagrams the setup of these two system's didn't take long.
Left: Drive Shaft and Pillow Block Mounting
Right: Oil Reservoir and Vapor Separator Mounting
Reactor Manufacturing
The reactors themselves were manufactured out of 18 gauge steel. Stainless steel was not used because the needed reactor life was expected to only be a couple hours. The inlets were cut from an 18 gauge steel sheet, while the tubes were rolled by the University of Idaho Facilities Shop. The inlet flanges, which mount to the engine mounting plate, were cut from 1/8 inch steel. The inlet flanges were all cut simultaneously with a manual mill. The needed holes in the tubes were cut by plasma cutter or die grinder. Once the inlet pieces, inlet flanges and tubes were prepared, the reactors were welded together by our team mentor, Nick Harker.
The thermocouple bungs were lathed from steel rod. The thermocouples and their mounts were purchased from Omega.
4 inch tangent ready to be welded.
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