Recalibrating and DAQ setup

Well work has been continuing since the last test, we have been working on setting up the DAQ so that the control interface is also recorded, such that we will have the time and duration for each event. This way we will know exactly when the solenoid is open and when ignition happens as well as when the solenoid is closed.

The pressure transducers have each been calibrated twice. We noticed that even though during the first round of calibration, the excitation voltage dropped from 28-23 V, we recorded ~ P psi=194.4x-27.34 where X is the voltage output. We recalibrate from a power supply, which will give us a much safer constant voltage. With this setup the transducers were P(psi)=204.1x-4.5 (between the two transducers, the y intercepts are a bit different). This however is fine, and we now have a reliable method of obtaining delivery pressure. Just to mention, we used a helium tank with a regulator and a well calibrated pressure dial indicator for pressure calibration. Not the best possible method, but this will do us well.
The pressure port was drilled today and looks great, we should have minimum pressure loss, though there is some worry that with all the extra volume that we have added that must be pressurized, there must be some way to fill this volume with some non combustible material. One though is krytox, however that would be Very expensive as it would require alot to fill the 90 elbow and lines for the transducer.
Other members machined another fuel grain and we should see two 10 second tests tomorrow around noon!