X-Git-Url: https://git.gag.com/?a=blobdiff_plain;f=rockets%2Fresearch%2F2017-batch-03.mdwn;h=096f6bfcb838d8eb7725603075b20d63ab00509f;hb=cb96cd832c0703ae747bad36079d96d7c4f147ab;hp=b390854c016cf0344da0774710ff89edcf37208a;hpb=c3209ea421e038c69530f8f7e085d842dc212eda;p=web%2Fgag.com
diff --git a/rockets/research/2017-batch-03.mdwn b/rockets/research/2017-batch-03.mdwn
index b390854..096f6bf 100755
--- a/rockets/research/2017-batch-03.mdwn
+++ b/rockets/research/2017-batch-03.mdwn
@@ -14,26 +14,38 @@ increased during melting to 300F indicated.
These grains were cast on 31 May 2017.
-Liner should be cut to 10.00" long for this 6-grain reload.
+Simulation says:
+
+
+
29mm 6-grain Erythritol #14 |
---|
Rating: | 43% H-162 | Max Pressure: | 5.92 MPa (859 psi) |
---|
Total Impulse: | 216 Ns | Specific Impulse: | 133 s |
---|
Max Thrust: | 206 N | Volume Loading: | 70% |
---|
Average Thrust: | 162 N | Fuel Mass: | 165 g |
---|
|
+
+
## Results ##
-* Grain 1, ?g gross, ?g net
-* Grain 2, ?g gross, ?g net
-* Grain 3, ?g gross, ?g net
-* Grain 4, ?g gross, ?g net
-* Grain 5, ?g gross, ?g net
-* Grain 6, ?g gross, ?g net
+Average casting tube mass 1.13g.
-With a 10.00" liner, 14/64" nozzle throat, buna-n o-rings, simulation says
-this makes a 37% H-156, 208 Ns, with about a 1.2 sec burn.
+Coring rods extracted easily, new hickory tube caps came off without too
+much effort. Slight cleanup at the top of each grain since propellant always
+seems to fillet around the coring rod. Grain average fill levels looks pretty
+good, with on the order of 1mm space at the top as expected.
-
-29mm 6-grain Erythritol #14 |
---|
Rating: | 43% H-162 | Max Pressure: | 859 psi |
---|
Total Impulse: | 48.5 lbf·s | Specific Impulse: | 133 s |
---|
Max Thrust: | 46.4 lbf | Volume Loading: | 70% |
---|
Average Thrust: | 36.4 lbf | Fuel Mass: | 5.82 oz |
---|
|
-
+* Grain 1, 26.57g gross, 25.44g net
+* Grain 2, 26.63g gross, 25.50g net
+* Grain 3, 26.65g gross, 25.52g net
+* Grain 4, 26.01g gross, 24.88g net (visible undefill)
+* Grain 5, 26.51g gross, 25.38g net
+* Grain 6, 26.75g gross, 25.62g net
-
-29mm 6-grain Erythritol #14 |
---|
Rating: | 43% H-162 | Max Pressure: | 5.92 MPa |
---|
Total Impulse: | 216 Ns | Specific Impulse: | 133 s |
---|
Max Thrust: | 206 N | Volume Loading: | 70% |
---|
Average Thrust: | 162 N | Fuel Mass: | 165 g |
---|
|
-
-
+Total of 152.34g propellant, vs 159g simulated.
+
+Note that after casting grains and cutting a liner to 10.0", I realized I'd
+mis-measured the case, and we actually had 10.4" of liner/propellant length
+to play with! Fix this for the next time we make grains... For now, we'll
+fly these grains in a correct length liner and live with the fact that we
+could have put another 0.4" of propellant in the case! That'd be another
+13 Ns according to the simulator...
+
+With a 10.40" liner, 14/64" nozzle throat, buna-n o-rings, simulation says
+this reload will be a 37% H-155, 208 Ns, with about a 1.2 sec burn.