More Than Load Resistance Testing
Sept 16, 2019 19:55:22 GMT -5
Post by ET on Sept 16, 2019 19:55:22 GMT -5
While I’m exploring the effect of load resistance there is also another test being done. The effect of using a recessed BP. To have a better idea what I’m referring to I need to outline another test parameter. The volumetric chamber restriction for incoming hot gas/flame flow. First, we need some volumetric measurements and percentage ratings with a given height.
Using a 5/8” height and a ½” diameter we have a volumetric measurement .123 cubic inches. Let’s assign this volumetric measurement as 100%.
Now a recess of 3/8”x5/8” has a volumetric measurement of .068 cubic inches. In relation to the ½” diameter it only has 55% volumetric spacing.
Now a recess of 5/16”x5/8” has a volumetric measurement of .048 cubic inches. In relation to the ½” diameter it only has 39% volumetric spacing.
With the ½” diameter when the hot gas/flame enters it disperses in all directions into the powder but in the process loses its intensity in a given volume. Now if we reduce the diameter that holds powder this restricts the dispersion of hot gas/flame and focuses the hot gas/flame intensity to a smaller volume of powder.
In my 10ml-II setup with the 5/16”x5/8” recessed BP I should have no problem using straight H4227. When I get to the 3/8” recessed BP I might not have a problem here either but where problems have been noted are with the Standard BP. Also keep in mind that reducing the travel length of the flame channel in a recessed BP more gas/flame intensity is also generated. In return more back pressure will build in the flame channel.
Now this post is meant for a technical review only. DO NOT alter your BP because of recessing a BP you may need to alter your head space to prevent dealing with blowback. For the 5/16” diameter recess I also need to machine the heads of the vents for fit. Here you also need a 10/32 tap to deepened the thread for a vent.
Now who said SML was simple, chuckle.
Ed
Using a 5/8” height and a ½” diameter we have a volumetric measurement .123 cubic inches. Let’s assign this volumetric measurement as 100%.
Now a recess of 3/8”x5/8” has a volumetric measurement of .068 cubic inches. In relation to the ½” diameter it only has 55% volumetric spacing.
Now a recess of 5/16”x5/8” has a volumetric measurement of .048 cubic inches. In relation to the ½” diameter it only has 39% volumetric spacing.
With the ½” diameter when the hot gas/flame enters it disperses in all directions into the powder but in the process loses its intensity in a given volume. Now if we reduce the diameter that holds powder this restricts the dispersion of hot gas/flame and focuses the hot gas/flame intensity to a smaller volume of powder.
In my 10ml-II setup with the 5/16”x5/8” recessed BP I should have no problem using straight H4227. When I get to the 3/8” recessed BP I might not have a problem here either but where problems have been noted are with the Standard BP. Also keep in mind that reducing the travel length of the flame channel in a recessed BP more gas/flame intensity is also generated. In return more back pressure will build in the flame channel.
Now this post is meant for a technical review only. DO NOT alter your BP because of recessing a BP you may need to alter your head space to prevent dealing with blowback. For the 5/16” diameter recess I also need to machine the heads of the vents for fit. Here you also need a 10/32 tap to deepened the thread for a vent.
Now who said SML was simple, chuckle.
Ed