P09451 Detailed Design Review
Notes from Review:
· Thermocouple groove analysis
o What is the average temperature within the groove?
o Boundary conditions inside the groove?
o Dissimilar Material
o Temperature may be exaggerated by square corners
o Why show a FEA model that contradicts your experimental results
· Data Collection/Feasibility
o There are more sophisticated tools in Labview that can automatically generate reports –Professor Wellin
o Could implement a separate routine to check validity of measurements/ display error messages
o Reasons for variability?
§ Measurement uncertainty alone?
§ Thermocouple accuracy?
§ Variability in finding peak power?
o Could test thermocouples under simpler conditions to determine their variability
· Power Unit
o Flexiforce sensors too far into centerline of unit
o Verify if flexiforce sensors will cause uneven loading on modules (sensors are only 0.008” thick)
o Tolerances between zones could cause uneven loading
o Timeline- machining may take longer than estimated
o Modules could be breaking due to plates not being solid(such as in previous leafblower design) vs the current design with zones
o High temperature thermal pads do exist and could help mitigate uneven loading –Emil
o Alignment pins could be used to guarantee the unit is flat
o Assembly could be completed on granite block to ensure flatness
o There may be different amounts of expansion in the lateral direction
o Could have shorter thermocouple grooves on one side and longer grooves going to the centerline on other side
o May need to look into surface finish to check and make sure it is smooth
o Could use an assembly jig for assembly between tests
o Alternate fins could be found from Niagra thermal products
· Piping
o Has there been a comparison between the experimental head loss and the calculated head loss for the current setup – No, current experimental data was used to estimate the loss across the power unit
o Could use pressure transducers to find actual head loss
o Could use an air flow switch hooked to the relay that turns on/off the heater as a fail safe for the no flow condition
§ Inline IC power of flow switch
o Complete cost analysis of custom header vs. piping
o Could thicker modules cause misalignment in piping?
§ Can add slop or oblong holes at attachment points
o Could use flex pipe, pvc or flex pvc for this flexibility
o PVC may take higher temperatures than rated, rating is for blowout at a given temperature/pressure situation not necessarily for breakdown of pvc itself
· Electrical/Peak Power control system
o Could change derivative search to search up the curve
o Could add range restrictions to avoid singularity
o Could use different algorithm for peak power similar to the root finding bisection method
o Smaller MOSFET? 30-35W?
o Plan to use op-amp to bump voltage? You can only get out of an op-amp as much as you put in
o Use DC-DC converter?
o Power supply specifications still needed
o Could we use the voltage from the DAQ instead of a power supply?
· Other
o Plan for how to not break modules?
o Give and take between module breakage and assembly time
o Bring together and document risks in single document
o In depth discussion of Labview user interface tabled until early next quarter- still in early stages, a review of the system would be much more beneficial at a later date when it is more fully developed