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Groups > sci.physics > #582896 > unrolled thread
| Started by | Bret Cahill <bretcahill@aol.com> |
|---|---|
| First post | 2016-06-04 12:47 -0700 |
| Last post | 2016-06-10 20:11 -0700 |
| Articles | 19 on this page of 39 — 7 participants |
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PV Dirigible Prop Alternative To Super Pressure Bret Cahill <bretcahill@aol.com> - 2016-06-04 12:47 -0700
Re: PV Dirigible Prop Alternative To Super Pressure jimp@specsol.spam.sux.com - 2016-06-05 02:11 +0000
Re: PV Dirigible Prop Alternative To Super Pressure Bret Cahill <bretcahill@aol.com> - 2016-06-04 22:22 -0700
Re: PV Dirigible Prop Alternative To Super Pressure jimp@specsol.spam.sux.com - 2016-06-05 17:36 +0000
Re: PV Dirigible Prop Alternative To Super Pressure Bret Cahill <bretcahill@aol.com> - 2016-06-05 13:52 -0700
Re: PV Dirigible Prop Alternative To Super Pressure jimp@specsol.spam.sux.com - 2016-06-05 22:56 +0000
Re: PV Dirigible Prop Alternative To Super Pressure Bret Cahill <bretcahill@aol.com> - 2016-06-08 00:57 -0700
Re: PV Dirigible Prop Alternative To Super Pressure jimp@specsol.spam.sux.com - 2016-06-08 19:27 +0000
Re: PV Dirigible Prop Alternative To Super Pressure Mahipal <mahipal7638@gmail.com> - 2016-06-08 19:16 -0700
Re: PV Dirigible Prop Alternative To Super Pressure jimp@specsol.spam.sux.com - 2016-06-09 02:52 +0000
Re: PV Dirigible Prop Alternative To Super Pressure Mahipal <mahipal7638@gmail.com> - 2016-06-09 06:55 -0700
Re: PV Dirigible Prop Alternative To Super Pressure jimp@specsol.spam.sux.com - 2016-06-09 16:22 +0000
Re: PV Dirigible Prop Alternative To Super Pressure Mahipal <mahipal7638@gmail.com> - 2016-06-09 13:23 -0700
Re: PV Dirigible Prop Alternative To Super Pressure jimp@specsol.spam.sux.com - 2016-06-09 21:14 +0000
Re: PV Dirigible Prop Alternative To Super Pressure Mahipal <mahipal7638@gmail.com> - 2016-06-09 14:49 -0700
Re: PV Dirigible Prop Alternative To Super Pressure Bret Cahill <bretcahill@aol.com> - 2016-06-09 19:46 -0700
Re: PV Dirigible Prop Alternative To Super Pressure jimp@specsol.spam.sux.com - 2016-06-10 05:53 +0000
Re: PV Dirigible Prop Alternative To Super Pressure Bret Cahill <bretcahill@aol.com> - 2016-06-10 10:07 -0700
Re: PV Dirigible Prop Alternative To Super Pressure jimp@specsol.spam.sux.com - 2016-06-10 17:49 +0000
Re: PV Dirigible Prop Alternative To Super Pressure jimp@specsol.spam.sux.com - 2016-06-10 21:22 +0000
Re: PV Dirigible Prop Alternative To Super Pressure Bret Cahill <bretcahill@aol.com> - 2016-06-10 19:40 -0700
Re: PV Dirigible Prop Alternative To Super Pressure jimp@specsol.spam.sux.com - 2016-06-11 05:00 +0000
Re: PV Dirigible Prop Alternative To Super Pressure Bret Cahill <bretcahill@aol.com> - 2016-06-11 01:13 -0700
Re: PV Dirigible Prop Alternative To Super Pressure jimp@specsol.spam.sux.com - 2016-06-11 17:38 +0000
Re: PV Dirigible Prop Alternative To Super Pressure Bret Cahill <bretcahill@aol.com> - 2016-06-08 00:58 -0700
Re: PV Dirigible Prop Alternative To Super Pressure noTthaTguY <abu.kuanysh05@gmail.com> - 2016-06-08 07:23 -0700
Re: PV Dirigible Prop Alternative To Super Pressure Bret Cahill <bretcahill@aol.com> - 2016-06-08 14:18 -0700
Re: PV Dirigible Prop Alternative To Super Pressure Sergio <invalid@invalid.com> - 2016-06-08 16:26 -0500
Re: PV Dirigible Prop Alternative To Super Pressure jimp@specsol.spam.sux.com - 2016-06-08 21:41 +0000
Re: PV Dirigible Prop Alternative To Super Pressure benj <nobodyxx@gmail> - 2016-06-08 20:23 -0400
Re: PV Dirigible Prop Alternative To Super Pressure jimp@specsol.spam.sux.com - 2016-06-09 00:34 +0000
Re: PV Dirigible Prop Alternative To Super Pressure benj <nobodyxx@gmail> - 2016-06-08 21:07 -0400
Re: PV Dirigible Prop Alternative To Super Pressure "hanson" <hanson@quick.net> - 2016-06-08 19:22 -0700
Re: PV Dirigible Prop Alternative To Super Pressure jimp@specsol.spam.sux.com - 2016-06-09 02:36 +0000
Re: PV Dirigible Prop Alternative To Super Pressure Bret Cahill <bretcahill@aol.com> - 2016-06-08 14:42 -0700
Re: PV Dirigible Prop Alternative To Super Pressure Bret Cahill <bretcahill@aol.com> - 2016-06-09 20:20 -0700
Re: PV Dirigible Prop Alternative To Super Pressure Bret Cahill <bretcahill@aol.com> - 2016-06-10 10:10 -0700
Re: PV Dirigible Prop Alternative To Super Pressure Bret Cahill <bretcahill@aol.com> - 2016-06-11 11:02 -0700
Re: PV Dirigible Prop Alternative To Super Pressure Bret Cahill <bretcahill@aol.com> - 2016-06-10 20:11 -0700
Page 2 of 2 — ← Prev page 1 [2]
| From | Bret Cahill <bretcahill@aol.com> |
|---|---|
| Date | 2016-06-10 19:40 -0700 |
| Message-ID | <5b47f95b-50b8-420e-b53b-63ef9afdecfe@googlegroups.com> |
| In reply to | #584269 |
> >> >> For the third time, why is the Reynolds number of any sphere, of any size, > >> >> and of any material always the same number? > >> > > >> > If the diameter or "characteristic dimension" is larger or smaller, you get a larger or smaller Nre. > >> > > >> > If the velocity in inversely proportional to diameter then the Nre is the same for all sizes of that shape in that fluid, i.e. a golf ball going 300 km/hr has the same Nre as a cyclist helmet going 30 km/hr and the air holes in the helmet actually _reduce_ drag like the dimples on the golf ball reduce drag. > >> > > >> > Maybe you meant the Reynolds number can be applied to any size object. > >> > >> The Reynolds number is directly proportional to the diameter of the > >> cross section, so the comment about size is incorrect. > >> > >> Equal sized spheres, no matter the material, be they soap bubbles or lead, > >> have the same Reynolds number. > > > > The speeds would need to be the same as well, a rare coincidence because > > soap bubbles always move slowly w/ respect to wind speed. > > As the Reynolds number is directly proportional to velocity, then different speeds => different Nre. > comparing > Reynolds numbers at differing speeds A golf ball going 300 km/hr has the same Nre as a cyclist helmet going 30 km/hr because the helmet ix 10X bigger than the ball. The air holes in the helmet actually _reduce_ drag like the dimples on the golf ball reduce drag. The reason is the speeds and diameters are different but the Nre are the same, 50K - 100K where dimpling works.
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| From | jimp@specsol.spam.sux.com |
|---|---|
| Date | 2016-06-11 05:00 +0000 |
| Message-ID | <qgis2d-315.ln1@mail.specsol.com> |
| In reply to | #584307 |
Bret Cahill <bretcahill@aol.com> wrote: >> >> >> For the third time, why is the Reynolds number of any sphere, of any size, >> >> >> and of any material always the same number? >> >> > >> >> > If the diameter or "characteristic dimension" is larger or smaller, you get a larger or smaller Nre. >> >> > >> >> > If the velocity in inversely proportional to diameter then the Nre is the same for all sizes of that shape in that fluid, i.e. a golf ball going 300 km/hr has the same Nre as a cyclist helmet going 30 km/hr and the air holes in the helmet actually _reduce_ drag like the dimples on the golf ball reduce drag. >> >> > >> >> > Maybe you meant the Reynolds number can be applied to any size object. >> >> >> >> The Reynolds number is directly proportional to the diameter of the >> >> cross section, so the comment about size is incorrect. >> >> >> >> Equal sized spheres, no matter the material, be they soap bubbles or lead, >> >> have the same Reynolds number. >> > >> > The speeds would need to be the same as well, a rare coincidence because >> > soap bubbles always move slowly w/ respect to wind speed. >> >> As the Reynolds number is directly proportional to velocity, > > then different speeds => different Nre. > >> comparing >> Reynolds numbers at differing speeds > > A golf ball going 300 km/hr has the same Nre as a cyclist helmet going > 30 km/hr because the helmet ix 10X bigger than the ball. > > The air holes in the helmet actually _reduce_ drag like the dimples on > the golf ball reduce drag. > > The reason is the speeds and diameters are different but the Nre are > the same, 50K - 100K where dimpling works. As Reynolds number is dependant on speed as you have realized, comparing Reynolds numbers of things at different speeds is pointless. As Reynolds number is dependant on speed as you have realized, talking about the Reynolds number of something without specifying speed is pointless. -- Jim Pennino
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| From | Bret Cahill <bretcahill@aol.com> |
|---|---|
| Date | 2016-06-11 01:13 -0700 |
| Message-ID | <ec05fe4b-f839-4b5b-993a-82517617a93f@googlegroups.com> |
| In reply to | #584313 |
> >> >> >> For the third time, why is the Reynolds number of any sphere, of any size, > >> >> >> and of any material always the same number? > >> >> > > >> >> > If the diameter or "characteristic dimension" is larger or smaller, you get a larger or smaller Nre. > >> >> > > >> >> > If the velocity in inversely proportional to diameter then the Nre is the same for all sizes of that shape in that fluid, i.e. a golf ball going 300 km/hr has the same Nre as a cyclist helmet going 30 km/hr and the air holes in the helmet actually _reduce_ drag like the dimples on the golf ball reduce drag. > >> >> > > >> >> > Maybe you meant the Reynolds number can be applied to any size object. > >> >> > >> >> The Reynolds number is directly proportional to the diameter of the > >> >> cross section, so the comment about size is incorrect. > >> >> > >> >> Equal sized spheres, no matter the material, be they soap bubbles or lead, > >> >> have the same Reynolds number. > >> > > >> > The speeds would need to be the same as well, a rare coincidence because > >> > soap bubbles always move slowly w/ respect to wind speed. > >> > >> As the Reynolds number is directly proportional to velocity, > > > > then different speeds => different Nre. > > > >> comparing > >> Reynolds numbers at differing speeds > > > > A golf ball going 300 km/hr has the same Nre as a cyclist helmet going > > 30 km/hr because the helmet ix 10X bigger than the ball. > > > > The air holes in the helmet actually _reduce_ drag like the dimples on > > the golf ball reduce drag. > > > > The reason is the speeds and diameters are different but the Nre are > > the same, 50K - 100K where dimpling works. > > As Reynolds number is dependant on speed as you have realized, Speed as well as diameter. A small high speed object can have the same Nre as a large low speed object. Dimpling would work on a motor vehicle going 3 km/hr. Most like to drive faster than that and it wouldn't amount to much savings adding in rolling resistance so very few people get a hammer and bang dents into their Prius.
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| From | jimp@specsol.spam.sux.com |
|---|---|
| Date | 2016-06-11 17:38 +0000 |
| Message-ID | <utut2d-9o9.ln1@mail.specsol.com> |
| In reply to | #584316 |
Bret Cahill <bretcahill@aol.com> wrote: >> >> >> >> For the third time, why is the Reynolds number of any sphere, of any size, >> >> >> >> and of any material always the same number? >> >> >> > >> >> >> > If the diameter or "characteristic dimension" is larger or smaller, you get a larger or smaller Nre. >> >> >> > >> >> >> > If the velocity in inversely proportional to diameter then the Nre is the same for all sizes of that shape in that fluid, i.e. a golf ball going 300 km/hr has the same Nre as a cyclist helmet going 30 km/hr and the air holes in the helmet actually _reduce_ drag like the dimples on the golf ball reduce drag. >> >> >> > >> >> >> > Maybe you meant the Reynolds number can be applied to any size object. >> >> >> >> >> >> The Reynolds number is directly proportional to the diameter of the >> >> >> cross section, so the comment about size is incorrect. >> >> >> >> >> >> Equal sized spheres, no matter the material, be they soap bubbles or lead, >> >> >> have the same Reynolds number. >> >> > >> >> > The speeds would need to be the same as well, a rare coincidence because >> >> > soap bubbles always move slowly w/ respect to wind speed. >> >> >> >> As the Reynolds number is directly proportional to velocity, >> > >> > then different speeds => different Nre. >> > >> >> comparing >> >> Reynolds numbers at differing speeds >> > >> > A golf ball going 300 km/hr has the same Nre as a cyclist helmet going >> > 30 km/hr because the helmet ix 10X bigger than the ball. >> > >> > The air holes in the helmet actually _reduce_ drag like the dimples on >> > the golf ball reduce drag. >> > >> > The reason is the speeds and diameters are different but the Nre are >> > the same, 50K - 100K where dimpling works. >> >> As Reynolds number is dependant on speed as you have realized, > > Speed as well as diameter. > > A small high speed object can have the same Nre as a large low speed object. Therefor talking about Reynolds number without speed is pointless. -- Jim Pennino
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| From | Bret Cahill <bretcahill@aol.com> |
|---|---|
| Date | 2016-06-08 00:58 -0700 |
| Message-ID | <d3c66b65-e0ba-47fa-b1b4-7f62a58f8eba@googlegroups.com> |
| In reply to | #582896 |
> From a distance all you would see is the inflatable blimp like prop. > > It would have no significant battery for overnight power. Instead during the day it would power toward the earth like an upside down helicopter to retard the gain in altitude as the He expanded. > > When it cooled at night the prop would auto rotate down to the lower altitude limit. > > To eliminate the huge torque from a counter rotating prop the major vertical axis prop is powered by smaller tip mounted props like a pin wheel. > > The Reynolds number would be yuge! <crickets>
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| From | noTthaTguY <abu.kuanysh05@gmail.com> |
|---|---|
| Date | 2016-06-08 07:23 -0700 |
| Message-ID | <d91c576c-47df-4dbf-b86f-b13b9b7b0ed6@googlegroups.com> |
| In reply to | #583777 |
again ... yummy > <crickets>
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| From | Bret Cahill <bretcahill@aol.com> |
|---|---|
| Date | 2016-06-08 14:18 -0700 |
| Message-ID | <852ad436-a99c-4ee8-9f6a-b5fd5408d0e4@googlegroups.com> |
| In reply to | #583777 |
> > From a distance all you would see is the inflatable blimp like prop. > > > > It would have no significant battery for overnight power. Instead during the day it would power toward the earth like an upside down helicopter to retard the gain in altitude as the He expanded. > > > > When it cooled at night the prop would auto rotate down to the lower altitude limit. > > > > To eliminate the huge torque from a counter rotating prop the major vertical axis prop is powered by smaller tip mounted props like a pin wheel. > > > > The Reynolds number would be yuge! > > <crickets> <CAP> crickets as perdicted
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| From | Sergio <invalid@invalid.com> |
|---|---|
| Date | 2016-06-08 16:26 -0500 |
| Message-ID | <nja2i1$imd$3@gioia.aioe.org> |
| In reply to | #583931 |
On 6/8/2016 4:18 PM, Bret Cahill wrote: >>> From a distance all you would see is the inflatable blimp like >>> prop. >>> >>> It would have no significant battery for overnight power. >>> Instead during the day it would power toward the earth like an >>> upside down helicopter to retard the gain in altitude as the He >>> expanded. >>> >>> When it cooled at night the prop would auto rotate down to the >>> lower altitude limit. >>> >>> To eliminate the huge torque from a counter rotating prop the >>> major vertical axis prop is powered by smaller tip mounted props >>> like a pin wheel. >>> >>> The Reynolds number would be yuge! >> >> <crickets> > > <CAP> crickets as perdicted > > ..........well....... build a proof of concept......
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| From | jimp@specsol.spam.sux.com |
|---|---|
| Date | 2016-06-08 21:41 +0000 |
| Message-ID | <p0gm2d-m4e.ln1@mail.specsol.com> |
| In reply to | #583931 |
Bret Cahill <bretcahill@aol.com> wrote: >> > From a distance all you would see is the inflatable blimp like prop. >> > >> > It would have no significant battery for overnight power. Instead during the day it would power toward the earth like an upside down helicopter to retard the gain in altitude as the He expanded. >> > >> > When it cooled at night the prop would auto rotate down to the lower altitude limit. >> > >> > To eliminate the huge torque from a counter rotating prop the major vertical axis prop is powered by smaller tip mounted props like a pin wheel. >> > >> > The Reynolds number would be yuge! >> >> <crickets> > > <CAP> crickets as perdicted You seem to get that a lot. I wonder why... -- Jim Pennino
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| From | benj <nobodyxx@gmail> |
|---|---|
| Date | 2016-06-08 20:23 -0400 |
| Message-ID | <5758b6ed$0$7258$b1db1813$15bdbe48@news.astraweb.com> |
| In reply to | #583946 |
On 06/08/2016 05:41 PM, jimp@specsol.spam.sux.com wrote: > Bret Cahill <bretcahill@aol.com> wrote: >>>> From a distance all you would see is the inflatable blimp like prop. >>>> >>>> It would have no significant battery for overnight power. Instead during the day it would power toward the earth like an upside down helicopter to retard the gain in altitude as the He expanded. >>>> >>>> When it cooled at night the prop would auto rotate down to the lower altitude limit. >>>> >>>> To eliminate the huge torque from a counter rotating prop the major vertical axis prop is powered by smaller tip mounted props like a pin wheel. >>>> >>>> The Reynolds number would be yuge! >>> >>> <crickets> >> >> <CAP> crickets as perdicted > > You seem to get that a lot. > > I wonder why... > > WARNING! NON-SCIENCE BABBLING DROOL.
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| From | jimp@specsol.spam.sux.com |
|---|---|
| Date | 2016-06-09 00:34 +0000 |
| Message-ID | <16qm2d-pcf.ln1@mail.specsol.com> |
| In reply to | #583974 |
benj <nobodyxx@gmail> wrote: > On 06/08/2016 05:41 PM, jimp@specsol.spam.sux.com wrote: >> Bret Cahill <bretcahill@aol.com> wrote: >>>>> From a distance all you would see is the inflatable blimp like prop. >>>>> >>>>> It would have no significant battery for overnight power. Instead during the day it would power toward the earth like an upside down helicopter to retard the gain in altitude as the He expanded. >>>>> >>>>> When it cooled at night the prop would auto rotate down to the lower altitude limit. >>>>> >>>>> To eliminate the huge torque from a counter rotating prop the major vertical axis prop is powered by smaller tip mounted props like a pin wheel. >>>>> >>>>> The Reynolds number would be yuge! >>>> >>>> <crickets> >>> >>> <CAP> crickets as perdicted >> >> You seem to get that a lot. >> >> I wonder why... >> >> > WARNING! > > NON-SCIENCE BABBLING DROOL. It seems BJ has gone into stalker mode on me. Next he will want to know where I live, went to school, what classes I took, how many children I have, and their ages among other things. -- Jim Pennino
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| From | benj <nobodyxx@gmail> |
|---|---|
| Date | 2016-06-08 21:07 -0400 |
| Message-ID | <5758c154$0$29114$c3e8da3$38634283@news.astraweb.com> |
| In reply to | #583981 |
On 06/08/2016 08:34 PM, jimp@specsol.spam.sux.com wrote: > benj <nobodyxx@gmail> wrote: >> On 06/08/2016 05:41 PM, jimp@specsol.spam.sux.com wrote: >>> Bret Cahill <bretcahill@aol.com> wrote: >>>>>> From a distance all you would see is the inflatable blimp like prop. >>>>>> >>>>>> It would have no significant battery for overnight power. Instead during the day it would power toward the earth like an upside down helicopter to retard the gain in altitude as the He expanded. >>>>>> >>>>>> When it cooled at night the prop would auto rotate down to the lower altitude limit. >>>>>> >>>>>> To eliminate the huge torque from a counter rotating prop the major vertical axis prop is powered by smaller tip mounted props like a pin wheel. >>>>>> >>>>>> The Reynolds number would be yuge! >>>>> >>>>> <crickets> >>>> >>>> <CAP> crickets as perdicted >>> >>> You seem to get that a lot. >>> >>> I wonder why... >>> >>> >> WARNING! >> >> NON-SCIENCE BABBLING DROOL. > > It seems BJ has gone into stalker mode on me. > > Next he will want to know where I live, went to school, what classes I took, > how many children I have, and their ages among other things. You are an amateur kook, jimp. You don't say "Next he will etc." you make the bold assertion that I've already said it! You should say: "BJ now wants to know where I live, went to school, what classes I took, how many children I have and their ages among other things." You are FAR too honest to take over from HVAC! Do I have to teach you EVERYTHING? WARNING! NON-SCIENCE BABBLING DROOL. Actually, you've said you live in Kalifornia (only you spell it differently) And I think you may have mentioned where you went to school but you can tell us again anyway. And what was you major? Engineering of some kind, right? Your kids are irrelevant to any discussion of physics.
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| From | "hanson" <hanson@quick.net> |
|---|---|
| Date | 2016-06-08 19:22 -0700 |
| Message-ID | <njak1e$67d$3@dont-email.me> |
| In reply to | #583987 |
"benj" <nobodyxx@gmail> wrote in message news:5758c154$0$29114$c3e8da3$38634283@news.astraweb.com... > On 06/08/2016 08:34 PM, jimp@specsol.spam.sux.com wrote: >> benj <nobodyxx@gmail> wrote: >>> On 06/08/2016 05:41 PM, jimp@specsol.spam.sux.com wrote: >>>> Bret Cahill <bretcahill@aol.com> wrote: >>>>>>> From a distance all you would see is the inflatable blimp like >>>>>>> prop. >>>>>>> >>>>>>> It would have no significant battery for overnight power. Instead >>>>>>> during the day it would power toward the earth like an upside down >>>>>>> helicopter to retard the gain in altitude as the He expanded. >>>>>>> >>>>>>> When it cooled at night the prop would auto rotate down to the lower >>>>>>> altitude limit. >>>>>>> >>>>>>> To eliminate the huge torque from a counter rotating prop the major >>>>>>> vertical axis prop is powered by smaller tip mounted props like a >>>>>>> pin wheel. >>>>>>> >>>>>>> The Reynolds number would be yuge! >>>>>> >>>>>> <crickets> >>>>> >>>>> <CAP> crickets as perdicted >>>> >>>> You seem to get that a lot. >>>> >>>> I wonder why... >>>> >>>> >>> WARNING! >>> >>> NON-SCIENCE BABBLING DROOL. >> >> It seems BJ has gone into stalker mode on me. >> >> Next he will want to know where I live, went to school, what classes I >> took, >> how many children I have, and their ages among other things. > > You are an amateur kook, jimp. You don't say "Next he will etc." you make > the bold assertion that I've already said it! > > You should say: > > "BJ now wants to know where I live, went to school, what classes I took, > how many children I have and their ages among other things." > > You are FAR too honest to take over from HVAC! Do I have to teach you > EVERYTHING? > > > WARNING! > > NON-SCIENCE BABBLING DROOL. > > > Actually, you've said you live in Kalifornia (only you spell it > differently) And I think you may have mentioned where you went to school > but you can tell us again anyway. And what was you major? Engineering of > some kind, right? Your kids are irrelevant to any discussion of physics. > WARNING! NON-SCIENCE BABBLING DROOL.
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| From | jimp@specsol.spam.sux.com |
|---|---|
| Date | 2016-06-09 02:36 +0000 |
| Message-ID | <4a1n2d-s2g.ln1@mail.specsol.com> |
| In reply to | #583987 |
benj <nobodyxx@gmail> wrote: > On 06/08/2016 08:34 PM, jimp@specsol.spam.sux.com wrote: >> benj <nobodyxx@gmail> wrote: >>> On 06/08/2016 05:41 PM, jimp@specsol.spam.sux.com wrote: >>>> Bret Cahill <bretcahill@aol.com> wrote: >>>>>>> From a distance all you would see is the inflatable blimp like prop. >>>>>>> >>>>>>> It would have no significant battery for overnight power. Instead during the day it would power toward the earth like an upside down helicopter to retard the gain in altitude as the He expanded. >>>>>>> >>>>>>> When it cooled at night the prop would auto rotate down to the lower altitude limit. >>>>>>> >>>>>>> To eliminate the huge torque from a counter rotating prop the major vertical axis prop is powered by smaller tip mounted props like a pin wheel. >>>>>>> >>>>>>> The Reynolds number would be yuge! >>>>>> >>>>>> <crickets> >>>>> >>>>> <CAP> crickets as perdicted >>>> >>>> You seem to get that a lot. >>>> >>>> I wonder why... >>>> >>>> >>> WARNING! >>> >>> NON-SCIENCE BABBLING DROOL. >> >> It seems BJ has gone into stalker mode on me. >> >> Next he will want to know where I live, went to school, what classes I took, >> how many children I have, and their ages among other things. <just more long winded babble> -- Jim Pennino
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| From | Bret Cahill <bretcahill@aol.com> |
|---|---|
| Date | 2016-06-08 14:42 -0700 |
| Message-ID | <412ee906-5a40-4119-a147-61b9f50a83b2@googlegroups.com> |
| In reply to | #582896 |
On Saturday, June 4, 2016 at 12:47:19 PM UTC-7, Bret Cahill wrote: > From a distance all you would see is the inflatable blimp like prop. > > It would have no significant battery for overnight power. Instead during the day it would power toward the earth like an upside down helicopter to retard the gain in altitude as the He expanded. > > When it cooled at night the prop would auto rotate down to the lower altitude limit. > > To eliminate the huge torque from a counter rotating prop the major vertical axis prop is powered by smaller tip mounted props like a pin wheel. > > The Reynolds number would be yuge! Any intelligent comments, i.e., the solar panels would weigh too much for 30 km altitude, the propulsion efficiency would be the product of the efficiency of the main prop and the tip props, they did these calculations in the 1950s when PV was $50,000/watt . . .?
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| From | Bret Cahill <bretcahill@aol.com> |
|---|---|
| Date | 2016-06-09 20:20 -0700 |
| Message-ID | <6c1468f2-4c8a-4e4c-8acf-259ade778759@googlegroups.com> |
| In reply to | #583942 |
> > From a distance all you would see is the inflatable blimp like prop. > > > > It would have no significant battery for overnight power. Instead during the day it would power toward the earth like an upside down helicopter to retard the gain in altitude as the He expanded. > > > > When it cooled at night the prop would auto rotate down to the lower altitude limit. > > > > To eliminate the huge torque from a counter rotating prop the major vertical axis prop is powered by smaller tip mounted props like a pin wheel. > > > > The Reynolds number would be yuge! > > Any intelligent comments, i.e., the solar panels would weigh too much for 30 km altitude, the propulsion efficiency would be the product of the efficiency of the main prop and the tip props, they did these calculations in the 1950s when PV was $50,000/watt . . .? Alternative idea: During the day compress air for ballast stored in spherical tanks. At night release the air as the He cooled. Bret Since the volume of the tanks increases with the
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| From | Bret Cahill <bretcahill@aol.com> |
|---|---|
| Date | 2016-06-10 10:10 -0700 |
| Message-ID | <d25f2be1-88bb-41c4-8390-147fae4ab033@googlegroups.com> |
| In reply to | #584159 |
> > > From a distance all you would see is the inflatable blimp like prop. > > > > > > It would have no significant battery for overnight power. Instead during the day it would power toward the earth like an upside down helicopter to retard the gain in altitude as the He expanded. > > > > > > When it cooled at night the prop would auto rotate down to the lower altitude limit. > > > > > > To eliminate the huge torque from a counter rotating prop the major vertical axis prop is powered by smaller tip mounted props like a pin wheel. > > > > > > The Reynolds number would be yuge! > > > > Any intelligent comments, i.e., the solar panels would weigh too much for 30 km altitude, the propulsion efficiency would be the product of the efficiency of the main prop and the tip props, they did these calculations in the 1950s when PV was $50,000/watt . . .? > > Alternative idea: > > During the day compress air for ballast stored in spherical tanks. At night release the air as the He cooled. OK, you goobers have exactly 24 hours to explain why the alternative idea would be a really dumb. (Hint: No calculations are required, just a couple of equations.) Here's a line for your answer: _______________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________
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| From | Bret Cahill <bretcahill@aol.com> |
|---|---|
| Date | 2016-06-11 11:02 -0700 |
| Message-ID | <ee8f0c1f-4b0c-4ab6-9cad-15406656a9fe@googlegroups.com> |
| In reply to | #584217 |
> > > > From a distance all you would see is the inflatable blimp like prop. > > > > > > > > It would have no significant battery for overnight power. Instead during the day it would power toward the earth like an upside down helicopter to retard the gain in altitude as the He expanded. > > > > > > > > When it cooled at night the prop would auto rotate down to the lower altitude limit. > > > > > > > > To eliminate the huge torque from a counter rotating prop the major vertical axis prop is powered by smaller tip mounted props like a pin wheel. > > > > > > > > The Reynolds number would be yuge! > > > > > > Any intelligent comments, i.e., the solar panels would weigh too much for 30 km altitude, the propulsion efficiency would be the product of the efficiency of the main prop and the tip props, they did these calculations in the 1950s when PV was $50,000/watt . . .? > > > > Alternative idea: > > > > During the day compress air for ballast stored in spherical tanks. At night release the air as the He cooled. > > OK, you goobers have exactly 24 hours to explain why the alternative idea would be a really dumb. (Hint: No calculations are required, just a couple of equations.) > > Here's a line for your answer: The super pressure balloon itself is the most efficient compressor, no new tanks needed. As with the vacuum lighter than air craft problem, there is no economy of scale or size advantage: Weight of ballast/wt. of tank = (volume of the ballast tank * pressure)/(hoop stresses * surface area) = (D^3 X P)/(P * D * D^2) = 1 Adding additional tanks would be adding additional weight for no reason, not to mention the weight of a compressor. Bret Cahill
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| From | Bret Cahill <bretcahill@aol.com> |
|---|---|
| Date | 2016-06-10 20:11 -0700 |
| Message-ID | <7c5aa504-4c0d-4de0-8579-f5d7c55e109b@googlegroups.com> |
| In reply to | #584159 |
> > > From a distance all you would see is the inflatable blimp like prop. > > > > > > It would have no significant battery for overnight power. Instead during the day it would power toward the earth like an upside down helicopter to retard the gain in altitude as the He expanded. > > > > > > When it cooled at night the prop would auto rotate down to the lower altitude limit. > > > > > > To eliminate the huge torque from a counter rotating prop the major vertical axis prop is powered by smaller tip mounted props like a pin wheel. > > > > > > The Reynolds number would be yuge! > > > > Any intelligent comments, i.e., the solar panels would weigh too much for 30 km altitude, the propulsion efficiency would be the product of the efficiency of the main prop and the tip props, they did these calculations in the 1950s when PV was $50,000/watt . . .? > > Alternative idea: > > During the day compress air for ballast stored in spherical tanks. At night release the air as the He cooled. OK, you goobers have exactly 15 hours to explain why the alternative idea would be a really dumb. (Hint: No calculations are required, just a couple of equations.) Here's a line for your answer: ______________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________
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