[sugpro] Re: Srm nozzle throat size

  • From: "Daniel Harrison" <daniel5841@xxxxxxxxxxx>
  • To: <sugpro@xxxxxxxxxxxxx>
  • Date: Thu, 19 Feb 2015 16:41:24 -0500

Wow, this program is awesome. This is exactly what I needed thank you!  

 

 

 

Dan

 

 

 

 

From: sugpro-bounce@xxxxxxxxxxxxx [mailto:sugpro-bounce@xxxxxxxxxxxxx] On 
Behalf Of Bill Kuker
Sent: Thursday, February 19, 2015 1:47 PM
To: sugpro@xxxxxxxxxxxxx
Subject: [sugpro] Re: Srm nozzle throat size

 

Yes, check out http://content.billkuker.com/projects/rocketry/software or 
https://github.com/bkuker/motorsim for the source code.

 

The math is more or less based on SRM.xls, but it has more options for grain 
geometry.

 

-Bill

 

On Thu, Feb 19, 2015 at 12:18 PM, Steve Peterson <steve_peterson@xxxxxxxxxxxxx> 
wrote:

I wrote my own--it's not that hard. Also, Bill Kuker wrote a program that is 
available--don't know the details, though. It's at content.billkuker.com
--Steve



On 02/19/2015 04:40 AM, Dan Harrison wrote:

Thanks for the replies .

Michael, that is a good idea with the bolt I will try that when I build my 
stand.

Steve, is there a different software you use to  sim motors? I know there is a 
program called burnsim but I was under the impression that was only for ap 
motors .



Thanks,
Dan






On Feb 17, 2015, at 1:08 PM, Michael Monteith (Redacted sender 
"michael_r_monteith@xxxxxxxxx" for DMARC) <dmarc-noreply@xxxxxxxxxxxxx> wrote:

One I've seen is where they pre load it with a weight and use a bolt underneath 
the load
cell and adjust it to limit the load cell being pushed any further.  Of course 
the bolt being
locked in place once it's adjusted.  That way you get the resolution by using a 
smaller
cell but protect it from being pushed too far in the case of miscalculation or 
catostrophic
event.  Probably should be a standard procedure anyway to protect the load cell.

Michael
--------------------------------------------
On Tue, 2/17/15, Steve Peterson <steve_peterson@xxxxxxxxxxxxx> wrote:

Subject: [sugpro] Re: Srm nozzle throat size
To: sugpro@xxxxxxxxxxxxx
Date: Tuesday, February 17, 2015, 1:02 PM

Hey Dan,

I can't answer the first
question since I don't actually use SRM, but
the calcs it does are pretty accurate--the real
question will be how
accurate/reliable is
your construction? The safe thing to do, if you've
never tested a motor before, is to start with a
load cell that is
capable of much more
thrust than you anticipate your motor will produce,
especially if/when it CATOs.

--Steve

On
02/17/2015 09:35 AM, Dan Harrison wrote:

Hello ,I'm looking to find some info

on using Richard nakka's srm.

    Is there a way to change the

nozzle throat size to match my motor? I tried using the
nozzle erosion box but I'm not sure if that is the right
way to do it.

How

accurate is srm ? I realize there are a lot of variables
.but generally speaking if it calculates 25 lbs max thrust
is that  usually close to what it will measure on a test
stand? The reason I ask is I'm building a test stand and
I want to make sure I put the correct load cell on  for my
first test.
Thanks,

Dan





 

 

 

Other related posts: