High-performance pulsejets for all, for free (as in beer)
Posted: Thu Jun 01, 2006 1:42 pm
I go away for awhile and just look what happens: folks claiming pulsejet "first to do's", as if they were truly the first ones.
If they wish to employ their native language more precisely...I recommend that they carefully qualify their future postings.
"Absence of evidence is not evidence of absence."
Do you people honestly think that the universe of pulsejet achievements is fully reflected within this forum of yours? No?
What is more amusing (to me anyway!), is that some may have claimed things as "first to do's", when they knew at the
time of their posting that someone else (yours truly) had already notified them off-forum that the "firsts" were attained.
So, let us take a brief look at three (3) of these valveless pulsejet "non-events":
1. duct acoustic temperature approaching (or exceeding) 750 K;
2. specific fuel consumption (SFC) less than 1.6, sans ejectors;
3. specific fuel consumption (SFC) at or near 1.0, sans ejectors.
Number 1. It was none other than yours truly who _introduced_ the concept of "effective acoustic temperature" into this
forum, back when "this forum" was the "old forum"... Where did you think that "magical" value of 750 K came from? Was
it possible that after the QD-80/88, that I never bothered to take a duct to this limit? In any event, it happened in 2004,
before 'Burning Grape', and then for independent confirmation, somewhat after 'Burning Grape' by Marten Klein, with his
K-PT 07X pulsejet. To be fair to Marten, he attained about 752 K. The value of 750 K is approximate, and varies with the
choice of fuel, among other things. If Marten wants to write, or not write, more about his achievement(s), it is up to him.
Of course, number 1. is a "non-event" because Snecma (and then Lockwood, and then Kentfield) had achieved this one.
__
Number 2. The QD-88 repeatedly demonstrated a minimum SFC of 1.3 in the second half of 2004 (folks need to read up
on the use of significant digits). This was not posted to the forum, but certain people were informed off-forum (by email).
This was obviously before 'Burning Grape', when the measured SFC of 1.6 by Bill Hinote's "mini-Escopeta" was reported.
Even wrt the "mini-Escopeta", what was not reported, at least on-forum, is that I directly helped Bill get his duct running
in the first place. If you could bother to read the old threads, you will find that this engine was "still-born". No matter, the
"mini" is Bill's engine. BTW, where do you think that the "mini's" nifty propane vapour "auto-starting" feature came from?
I chose the value of 1.6 as we have historical documents demonstrating that this level of SFC was reached decades ago;
therefore, this too, is a "non-event". As is the "auto-start". The best we can do so far is re-capture Snecma's past glories.
__
Number 3. The "Big 1.0". Someone (anyone want to guess who?) was informed _before_ 'Burning Grape', in writing, that
a test of a so-called "sub-unity" valveless pulsejet was imminent. Did I lie? You can believe whatever you want, and from
what I have read in this forum, you do...Facts be damned. This is too often the land of "ghosts and fairies". Sad, but true.
To be fair, the actual test runs had not been completed by 'Burning Grape'; however, someone (guess who) decided to go
their own way shortly after 'Burning Grape' and was therefore never informed. In any case, I have a solution for this point:
*** READ THE FOLLOWING SECTION CAREFULLY ***
I am going to upload to this forum _all_ of the information necessary for any of you to construct a valveless pulsejet that
is able to attain a SFC of approximately 1.0 kgf/kg/hr (lbf/lbm/hr), if not less, _without_ the use of augmenters. To make
my offer "double-sweet", the first pulsejet that I am providing will be a 250N-class (55 lbf) "Lockwood-Hiller replacement".
I will start with a fully dimensioned duct and the dimensions for fuel injector feed(s) (propane vapour). If necessary, I will
provide a design for a suitable fuel injector; however, "advanced" or "special" injectors will not be required. Even humble
"swizzle stick" injectors will not push SFC past perhaps 1.5 kgf/kg/hr (this is still "world-class" performance). You always
have the option of buying injectors from Eric Beck; I am sure that his designs are sound (and it is for a very good cause).
It is my intention to "design-to-spec"; however, if there is any demand, I will upload a dimensioned duct that can be put
together (primarily) from COTS (commercial off-the-shelf) components, e.g., Burns Stainless (performance may be lower).
So, if any one wants to power a go-kart (or whatever), and not want (or need) anything more potent that propane vapour,
all you need to do is follow the plans that I will upload. Smaller engines and different configurations may follow, as my time
permits (and if there is any response to justify such effort). The first 55 lbf pulsejet design will be uploaded within 20 days.
Of course, it goes without saying, that _all_ of this information will be provided at no charge, for your non-commercial use.
__
There you have it. Like it or leave it, it matters not to me; this "look at me, flash it, hide it" ride is coming to an end. Soon.
Let the pulsejet "arms race" begin...my "guns" will be _free to everyone_, even for those of you who dislike me the most.
Best regards,
Störgröße M.
If they wish to employ their native language more precisely...I recommend that they carefully qualify their future postings.
"Absence of evidence is not evidence of absence."
Do you people honestly think that the universe of pulsejet achievements is fully reflected within this forum of yours? No?
What is more amusing (to me anyway!), is that some may have claimed things as "first to do's", when they knew at the
time of their posting that someone else (yours truly) had already notified them off-forum that the "firsts" were attained.
So, let us take a brief look at three (3) of these valveless pulsejet "non-events":
1. duct acoustic temperature approaching (or exceeding) 750 K;
2. specific fuel consumption (SFC) less than 1.6, sans ejectors;
3. specific fuel consumption (SFC) at or near 1.0, sans ejectors.
Number 1. It was none other than yours truly who _introduced_ the concept of "effective acoustic temperature" into this
forum, back when "this forum" was the "old forum"... Where did you think that "magical" value of 750 K came from? Was
it possible that after the QD-80/88, that I never bothered to take a duct to this limit? In any event, it happened in 2004,
before 'Burning Grape', and then for independent confirmation, somewhat after 'Burning Grape' by Marten Klein, with his
K-PT 07X pulsejet. To be fair to Marten, he attained about 752 K. The value of 750 K is approximate, and varies with the
choice of fuel, among other things. If Marten wants to write, or not write, more about his achievement(s), it is up to him.
Of course, number 1. is a "non-event" because Snecma (and then Lockwood, and then Kentfield) had achieved this one.
__
Number 2. The QD-88 repeatedly demonstrated a minimum SFC of 1.3 in the second half of 2004 (folks need to read up
on the use of significant digits). This was not posted to the forum, but certain people were informed off-forum (by email).
This was obviously before 'Burning Grape', when the measured SFC of 1.6 by Bill Hinote's "mini-Escopeta" was reported.
Even wrt the "mini-Escopeta", what was not reported, at least on-forum, is that I directly helped Bill get his duct running
in the first place. If you could bother to read the old threads, you will find that this engine was "still-born". No matter, the
"mini" is Bill's engine. BTW, where do you think that the "mini's" nifty propane vapour "auto-starting" feature came from?
I chose the value of 1.6 as we have historical documents demonstrating that this level of SFC was reached decades ago;
therefore, this too, is a "non-event". As is the "auto-start". The best we can do so far is re-capture Snecma's past glories.
__
Number 3. The "Big 1.0". Someone (anyone want to guess who?) was informed _before_ 'Burning Grape', in writing, that
a test of a so-called "sub-unity" valveless pulsejet was imminent. Did I lie? You can believe whatever you want, and from
what I have read in this forum, you do...Facts be damned. This is too often the land of "ghosts and fairies". Sad, but true.
To be fair, the actual test runs had not been completed by 'Burning Grape'; however, someone (guess who) decided to go
their own way shortly after 'Burning Grape' and was therefore never informed. In any case, I have a solution for this point:
*** READ THE FOLLOWING SECTION CAREFULLY ***
I am going to upload to this forum _all_ of the information necessary for any of you to construct a valveless pulsejet that
is able to attain a SFC of approximately 1.0 kgf/kg/hr (lbf/lbm/hr), if not less, _without_ the use of augmenters. To make
my offer "double-sweet", the first pulsejet that I am providing will be a 250N-class (55 lbf) "Lockwood-Hiller replacement".
I will start with a fully dimensioned duct and the dimensions for fuel injector feed(s) (propane vapour). If necessary, I will
provide a design for a suitable fuel injector; however, "advanced" or "special" injectors will not be required. Even humble
"swizzle stick" injectors will not push SFC past perhaps 1.5 kgf/kg/hr (this is still "world-class" performance). You always
have the option of buying injectors from Eric Beck; I am sure that his designs are sound (and it is for a very good cause).
It is my intention to "design-to-spec"; however, if there is any demand, I will upload a dimensioned duct that can be put
together (primarily) from COTS (commercial off-the-shelf) components, e.g., Burns Stainless (performance may be lower).
So, if any one wants to power a go-kart (or whatever), and not want (or need) anything more potent that propane vapour,
all you need to do is follow the plans that I will upload. Smaller engines and different configurations may follow, as my time
permits (and if there is any response to justify such effort). The first 55 lbf pulsejet design will be uploaded within 20 days.
Of course, it goes without saying, that _all_ of this information will be provided at no charge, for your non-commercial use.
__
There you have it. Like it or leave it, it matters not to me; this "look at me, flash it, hide it" ride is coming to an end. Soon.
Let the pulsejet "arms race" begin...my "guns" will be _free to everyone_, even for those of you who dislike me the most.
Best regards,
Störgröße M.