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February 7, 2017

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Storm Chase Update 5.24.2016: When Pigs Fly - or Not

May 25, 2016

 

I chased storms near hard hit Shamrock today, no hail, just too late on the scene. Last night on the way from Clarendon to Lubbock, somewhere around Silverton I ran over two small wild hogs, about 20-30 lb. size.  Lost one hub cover and had to drive with pig guts flopping on the drive line (flop, flop, flop) for about 10 minutes.  Had to slow to about 40 mph, but the pig guts eventually wore out.  Not sure of any other damage.  I will get the front end alignment checked while in Lubbock this week.  No luck catching hail yesterday, too far to drive and not enough time to respond.

 

Equipment update

The new hitch and couple work great, no more sway and the trailer pulls nicely, even at 70+mph.  Not that I drive 70+, but going down hills we have hit 70 mph several times and still pulls great.  No more aggressive braking to stop a dangerous sway.  The freezer is working great and yesterday I drove from Hutto to Clarendon, via Altus OK chasing some storms and it cooled the trailer down below 30 oF while in route.  The door insulation job that Lynn Bell did is still working great! 

 

The new load cell will be delivered today and Carol will forward to me at my son’s house in Lubbock such that I have it no later than Friday noon.  I have also ordered a reserve digital transducer (measures hail stone compression compression/expansion distance) and will order a second load cell this morning.  We cannot afford to miss any more opportunities due to equipment failures and this will provide us a backup of the two most critical (and exposed) instruments in our analysis system.  Without these instruments we are shut down.  If I have collected samples yesterday I could only have measured the volume, weight and opacity, the compressive strength and compression/expansion would have had to wait until the new load cell is delivered. 

 

BTW the cost of the load cell is $585.00 and the digital transducer is $245.00.  Not cheap, but not nearly as expensive as missed data.  The load cell was damaged (over loaded) by me by leaving the load cell in place while in trailer transport mode.  We place a wood block in the press and compresses the block so it will not flop around and come apart while we are driving.  There is a fair amount of work that has to be done to put the trailer and van in transport mode and then back to data collection mode and it just takes some time.  This is one reason we want to drive with all the systems on so that we do not have to wait the required 45 minutes for the Data Acquisition Unit (DAQ) to warm up.  The new pure sine wave power inverter is working great and our “dirty” power problems have been eliminated.

 

 

Test Methods

I would like to thank Greg Winterton who came to the lab Monday the 23rd to help me work though the procedure for the calorimetric method that we use to determine the liquid water content trapped inside the hail stone.  I have developed a mathematical method for making this same determination; however,  it must be confirmed and the method that Greg and I will be performing will do this for me.  The purpose for this is that we need to know the relative % of ice, liquid water, and air that are in a hailstone.  These three items will allow us to plot the data on a graph and compare them to other values we measure such as density, opacity, compressive strength, etc.  This will allow us to make trend lines that we can make grouping of hail stones that are similar and those that are different.  Different can be caused by several things such as temp, density, and hail stone structure.  Gary Treider will be cutting about 1/12 of the stones in half and photographing their internal structure.  Structure is important and may be a big role in hailstone compressive strength.  What we need is a way of determining hailstone structure without having to destroy the hailstone in doing the analysis.  It may be that we can make this determination based upon the other Non-Destructive (NDS) methods.  It will be interesting to see how this shakes out.

 

Confirmation Testing

We need to do some confirmation testing of the opacity method.  This will involve testing the same stone many times.  I am still working my way through this one, but will be calling for help from folks to come to the lab and help me get this done.  I make take some freezer ice balls with me to DFW next week and we could do the testing in the trailer while I am at a job site!

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