Conversion Procedure Manual For use with developing future iterations of MSD Project P13051

Transcription

1 PIV in Lung Model Conversion Procedure Manual For use with developing future iterations of MSD Project P13051

2 Table of Contents Introduction... 3 Lung Model Tank... 4 Piping and Tubing... 6 Pressure Sensors... 7 Model... 8

3 Introduction This conversion document is designed for MSD Project P13051, PIV in Lung Model. The conversion document is made to help whoever works on this project in the future will have adequate documentation of exactly what is required to transfer the current 17 outlet system using a jury rigged lung model into the 81 outlet rapid-prototyped system that was originally intended.

4 Lung Model Tank The current lung model tank is a 2 x2 x2 cube made out of a clear acrylic, with a hole in the top to access the interior. There are two holes cut along the bottom of the tank on one corner of the tank. In order to accommodate the full 81 outlet model, 6 additional holes will need to be routed into the side of the tank, and the remaining 6 manifolds (already manufactured) will need to be affixed via super glue and silicone. For the routing of the holes please contact Rob Kraynik in the machine shop, as he routed the original 2 holes. Obviously the tank will need to be drained first, this teams reccomendation is to unplug one of the holes in the manifolds and let the water drain out through that, then when no more can come out simply tilt the tank into a sink and dump the rest. It should be noted that you should not move the tank when full of liquid under any circumstances. The tank is not made to withstand the stresses that moving liquid could cause and it may rupture. After the holes are drilled and the manifolds are attached, take the 6 new manifolds and put a 3/8 NPT to 1/2 tube adapter in both sides of each hole. Wrap threads with pipe thread tape before screwing in adapters to prevent leakage. Next, unplug the unused outlets in the two existing thru wall manifolds and replace with a 3/8 NPT to 1/2 tube adapter on both side of each hole (copy what was done for the other manifold outlets).

5 Lastly, the current tank lid will not be suitable for continued use as is. Suggestions to improve it are to purchase a thinker piece of acrylic to better support the model or utilize additional screws in the corner of the piece, as currently the coreners of the acrylic are pulling up as it bends.

6 Piping and Tubing The tubing in the interior of the tank hooked up to the model is currently 1/4 OD tubing, utilizing a different hookup structure would allow 1/4 ID tubing and therefore allow less pressure buildup. Additionally, if flexible enough ½ tubing could be found, it would be even more ideal for the interior of the tank. The current system utilizes ½ tubing but only at the manifolds as the thick tubing did not allow the model enough flexibility.

7 Pressure Sensors An additional 79 pressure sensors will be needed to be purchased if every outlet is to have a sensor. Alternatively the manifold method can be done, which will utilize only 18 sensors, and instead these sensors will be fed from 20 manifolds that allow each sensor to service 4 outlets. This decision will be left up to the sponsor, Dr. Robinson. In addition, the sensors will need to be checked for calibration and to insure they follow the appropriate. They have not been fully calibrated as of this document, as only 2 have been purchased, not allowing compare trend lines and the ability to insure accuracy from sensor to sensor.

8 Model The model that will be used is the piece that will require the most amount of work to convert, but is also know the least about the exact methods to do so. For all other sections it has already been accomplished, albeit in a smaller scale. For the lung model a placeholder was utilized but certain technical roadblocks prevented the team from accomplishing the rapid prototyping of a 3D Lung model. For the design of the CAD lung model, the team recommends the following additions be added to the computer model so it is easier to utilize in the system: Firstly the lung model and mouth model must be attached together into one computer model file. The entire negative model covered with 5mm thick (or thicker depending on the recommendations of the rapid prototyping company) coating which will be the actual material of the lung model. A 3-4 threaded hole in along the back of the lung model (parallel to the esophagus) in an extra block of material that will allow the screw from the model positioning system to hold the model in place. Barring that, a large enough flat platform on the top of the model which allows easy adhesion so the model can be controlled. Struts in between very thin outlets which could be identified as weak points.

9 Threaded or barbed outlets which allow the ability to screw on tubing and provide a much stronger connection. An adapter at the mouth to allow the pump to be able to pump liquid into the model will be necessary, either a screw or barbed adapter is recommended for this to insure the large amount of pressure while running the system at high flow rates does not knock the piping off.

10 Pump For the pump, it is known that additional manifolds will have to be made, 3 in total of manifold #1, with instructions in the assembly documents. As of writing this document however, the pump has not yet arrived due to underestimation of the lead time. With such a powerful pump and high flow rates, the system is in serious danger of becoming damaged during testing. Extensive testing at lower flow rates and gradual increase of pressure is recommended by this team, to insure that nothing this is difficult to replace (or irreplaceable) becomes damaged. When the pump is able to run, it should be run with the pump hooked up drawing liquid through the reservoir and utilizing the ball valves provided in order to switch the direction of the pump when doing exhalation.