[Tech] HPR Tech Article - Thrust Coefficient Losses from Straight-Cut Throats

Need a break from reviewing my latest tech article. Let's see how things are going on RMR.
Humm... Not so good....
Jerry Irv> >
Unfortunately with you trashing things here, many people have moved on to other newsgroups. In particular, many of the technical people have moved on. The way this Tech thread got trashed, I can see why.
This unfortunately makes my job more difficult, because now I'll be having to post technical results to 4 or 5 different newsgroups, instead of one. The technical community here has really splintered. Oh well. Thank you Jerry.
If these Tech thread discussions turn into a waste of time like the last one, I'll just do (1); announce that the tech article is out, and here's the HPR issue to find it in.
By your third post you were making personal attacks, which by the way had nothing to do with nozzle thrust coefficients.
Great example right in your last post. "...taken to excess WRT issues raised regarding rules, regs, ethics, and policies" has nothing to do with nozzle thrust coefficients. Start another Tripoli attack thread, don't pollute a Tech thread with this garbage.
It doesn't hurt me. It hurts the thread. And wastes my time and everyone else's time by trashing the thread.
I'm getting it now. The best self-editing is just "ignore Jerry".
I'm not going to bother looking up and posting here your numerous "I invented High Power Rocketry" posts. "I invented High Power Rocketry" is a pretty broad statement, sure sounds like to me "I invented [everything in] High Power Rocketry".
Check my third post, a little nozzle survey I did checking out your motors on your web site. Clearly not the majority with L/D's = 0.30. You took my information, and regurgitated it back to me.
Which you're right, I should ignore. Good advice.
CONSUMER
Another great example right in your last post, more Tripoli attacks, blah, blah, blah. What does this have to do with nozzle thrust coefficients?
Well I've figured this out too. Publish or perish. I'll publish. Jerry perish? :)
If next time you claim, "I've been doing this for years, but it was proprietary, yada, yada, yada", ya know, publish it, with real data, or sit down and shut up.
Keep exit plane in same location. Keep convergent in the same location. Shorten up straight-cut throat L/D by rounding the throat entrance. Recommended rounding radius is in the tech article.
There's a concept; buy the tech article, and actually read it!
Well, I'll come and go here when I can afford to waste the time, I guess. In fact on many of these RMR arguments all you've really proved Jerry is that you have more time to waste at this than I do.
So in other words, I should ignore you? Good advice. I'll take your advice.
In fact I'm wasting my time with these very key strokes. But, not for long. I've got to look up blast tube data for another thread. You know, something useful.
So why did you even participate in this thread? Jeez. Chuck Rogers snipped-for-privacy@aol.com
Reply to
CRogers168
Loading thread data ...
Here, I started a new thread so you can address the issues in comfort without "spoiling" your "tech thread".
Jerry
Reply to
Jerry Irvine
Good idea. With the optimization article at L/D of 0.45 and the blast tube data showing about 90% performance, it appears you can design a much wider range of motor nozzles now.
Jerry
Reply to
Jerry Irvine
Jerry:
If you had read the tech article, you'd know that there was some spread in the data around the jump in the CF Efficiency Factor at a straight-cut throat L/D of 0.45. That's why I proposed using a straight-cut throat L/D of 0.40 for design margin to make sure that you get the jump in the CF Efficiency Factor and hence the jump in nozzle performance.
If you had read the blast tube thread with any degree of carefulness, you would have read that the blast tube nozzles which had rounded throats had CF Efficiency Factors of 0.99-1.0, which I'd approximate at 0.99. From the tech article conical nozzles with rounded throats, on the high performance trend line, had a CF Efficiency Factor of 0.99. Hence a conical nozzle with a rounded throat, and a conical nozzle with a rounded throat at the end of a blast tube, had a CF Efficiency Factor of 0.99. My conclusion therefore from the initial data was that there was essentially no thrust coefficient loss from the blast tube, at least no loss large enough to be noticed within the experimental spread in the CFactual data from which the CF Efficiency Factor is derived.
Chuck Rogers snipped-for-privacy@aol.com
Jerry Irv> >
Reply to
CRogers168
Jerry, it still shows up as a sub-thread under google, something I think you were well aware of. You should have started a completely new thread.
So now all your garbage just flows on.
Freaking unbelievable how you have completed trashed this tech thread. You even tried to make another technical comment up at the top of the thread, and you got that wrong too! (See below.)
Are you going to make ANY useful contribution to this thread?
Chuck Rogers snipped-for-privacy@aol.com
Jerry:
If you had read the tech article, you'd know that there was some spread in the data around the jump in the CF Efficiency Factor at a straight-cut throat L/D of 0.45. That's why I proposed using a straight-cut throat L/D of 0.40 for design margin to make sure that you get the jump in the CF Efficiency Factor and hence the jump in nozzle performance.
If you had read the blast tube thread with any degree of carefulness, you would have read that the blast tube nozzles which had rounded throats had CF Efficiency Factors of 0.99-1.0, which I'd approximate at 0.99. From the tech article conical nozzles with rounded throats, on the high performance trend line, had a CF Efficiency Factor of 0.99. Hence a conical nozzle with a rounded throat, and a conical nozzle with a rounded throat at the end of a blast tube, had a CF Efficiency Factor of 0.99. My conclusion therefore from the initial data was that there was essentially no thrust coefficient loss from the blast tube, at least no loss large enough to be noticed within the experimental spread in the CFactual data from which the CF Efficiency Factor is derived.
Chuck Rogers snipped-for-privacy@aol.com
Jerry Irv> > > Sounds like some things I need to incorporate into the next version of
Reply to
CRogers168
You said in your post you understood many had not had a chance to even get the article yet. I am certainly in that catagory as you well know because you FORCE it.
So I was honoring the spirit of the thread with a tech question (molded part drawing) you initially did not want to answer because you had several criticisms of me you wanted to vent.
Jerry
In hindsight I may have made a typo of 0.90% in my comment on burnsim?
Oops. Sorry. Fat fingers :)
Do you have any intention of addressing questions posed to you about your PUBLIC policies and practices at TRA?
Jerry
Reply to
Jerry Irvine
Nope. I don't use Google and I suggest you do not either.
So use a tiny fraction of your intellectual capacity and do a bit of self filtering and start by addressing, directly, the two tech posts I raised. I felt they were the most valuable questions for those few remaining solid motor makers. You may not agree. Fine. Consider the question and address the spirit.
But so long as YOU fixate on your accusatory tone WITHOUT also answering the tech questions YOU solicited, you are THE PROBLEM.
See? Here is my evidence of the source of the negative tone Chuck.
In another reply I conceeded making a typographical error in the "burnsim" post. Again, I profusely apologize.
Jerry
Reply to
Jerry Irvine
So you admit you didn't read it. How can anyone with a brain discuss a paper that they haven't read? Oh yeah we're talking about Jerry.
There are so many catagories to choose from. Poor Jerry.
Reply to
Phil Stein
blah blah blah blah blah
Poor Jerry - can't get any respect. Guess his mom never told him he had to earn it.
Reply to
Phil Stein
Well, he's on the TRA BOD, and has been for well over a decade, so he answers to every one who has been a member during that period.
And as a TRA officer he lied to the NAR about the certification status of a bunch of AT motors. No action was ever taken by either organization about that.
Bob Kaplow NAR # 18L TRA # "Impeach the TRA BoD" >>> To reply, remove the TRABoD!
Reply to
Bob Kaplow
If you feel that way, send a request to HQ. I still don't think there is any need for Chuck to answer to Jerry. It's not like Jerry has anything new to ask about or to accuse Chuck of.
Reply to
Phil Stein

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