Thursday, December 17, 2020
Anatomy Of A Pack Saddle
Tuesday, December 1, 2020
Planetary Orbital Eccentricity Updated
In my previous post on the subject I mentioned how I didn't have the eccentricity of the Earth's orbit quite right yet. I have pretty much corrected that. The old data set and the new are shown below the break.
Friday, November 27, 2020
No not that Climatology
Well, back to writing some posts. A fellow I know needed me to help him move some cattle. That meant quite a bit of time in the saddle, and then hauling winter feed to the new location. Oh great I get to ride drag, and no that doesn't mean riding in women's clothes. It's where you get to smell the cow flatulence all day and eat dust for hours on end at the back of the drive.
I have worked with a lot of people over the years in what I call planetary sciences. This also includes atmospheric research. Over the years I have built a number of instruments and conducted experimental studies in support of this type of work so I naturally developed an interest in the subject. One aspect of this field is obviously the climate of earth both in the past and the present. The present day arguments over modern climate change don't hold much interest for me but the past or paleoclimate studies do.
Wednesday, November 11, 2020
What Do You Believe?
Given our last election and some of the rather unusual events I thought I would create a mathematical model to explore this strange space. So the first thing to do is to express the thing in some form and see if it makes sense. An exponential model first comes to mind such as:
Saturday, November 7, 2020
Explosives Applications: The Shaped Charge
One major use for explosives is in the oil and gas industry to complete a well. For a simple well the process is straightforward. The well is drilled, cased and then perforated. This involves inserting a length of tubing with a series of shaped charges along it's length into the cased well and setting off the charges that perforate the casing and the oil and gas bearing strata.
A shaped charge in its simplest form is nothing more than a metal cone surrounded by explosives. The charge is end initiated and the explosive collapses the conical liner into a jet of material that penetrates at very high velocity. The jet penetrates in the same manner as I previously posted about hypervelocity penetration. A model of a simple 65 degree angled shaped charge is shown in the first video. As the detonation proceeds up the charge the cone collapses inward in a symmetrical manner with an upwards momentum. At the collision point the cone coalesces into a jet of material that has a high velocity and has a final form of a long slender rod.
Tuesday, October 27, 2020
Over the Hills and Through The Woods...
It's getting close to that time of the year when the snow flies. I like to hit the mountains once there is a fair amount of snow. These pictures are from last winter after the first storm. There was 3 feet of snow in that storm. That's me snowshoeing in (uphill, both ways) with a sleigh full of supplies.
Mush, Mush I say. |
Sweet Seclusion. |
How About a Nice Curve Fit?
I've been meaning to do this for some time. That is developing a Windows based system for fitting equation of state terms to experimental data, rather then relying on other people's fitting routines. One of the more common equations of state (P-v relationship) people like to use in the explosives world is the Jones-Wilkins-Lee (JWL) equation of state. There are others but I won't go into them for now. One form of the JWL equation of state for the products of detonation is given by:
The data to fit to has to be in an Excel file and can be imported directly into the application. The data file needs to be in the form displayed. The pressure units are in GPa.
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Dogs. I've had a lifelong relationship with horses and dogs, and if pressed I couldn't give you an answer as to which is my favorite...
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During my undergraduate days I ran a shock physics lab primarily studying the welding window for explosively welding dis-similar materials. ...
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I've finished up most of my horticultural work for the year and soon it will be time for the plant world to rest for the winter. We don...