Error by ODEs solution

#21 Pubblicato: 18/12/2023 13:34:40

Valery Ochkov

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Wrote

Thanks, Alvaro!
My email OchkovVF@mpei.ru

Alvaro!
I am waiting for your email!
Send me one letter!

#22 Pubblicato: 18/12/2023 13:42:28

Valery Ochkov

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3 stages variation.

Checking with Tsiolkovsky rocket equation in a gravitational field with several stages
Alvaro.

There is such a Meshchersky equation. In the West it is called differently.

Уравнение Мещерского

В отношении И.В. Мещерского память потомков совершила вопиющую несправедливость. Дифференциальное уравнение движения тела переменной массы, которое И.В. Мещерский вывел и опубликовал ещё в 1897 году, спустя 31 год (!) было (по незнанию трудов Мещерского) заново выведено итальянским математиком Туллио Леви-Чивита. К сожалению, как это уже не раз бывало, о русском первооткрывателе на Западе забыли, и это уравнение стали называть "уравнением Леви-Чивита". (https://borisgen.livejournal.com/22811.html)

#23 Pubblicato: 19/12/2023 15:30:51

Valery Ochkov

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New versions
Polet na Lunu.docx (496,8 KiB) scaricato 933 volta(e).
Rakete-1.sm (17,75 KiB) scaricato 1509 volta(e).
Rakete-2.sm (17,14 KiB) scaricato 1517 volta(e).

#24 Pubblicato: 22/12/2023 13:21:28

Valery Ochkov

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New versions
Polet na Lunu.docx (496,8 KiB) scaricato 933 volta(e).
Rakete-1.sm (17,75 KiB) scaricato 1509 volta(e).
Rakete-2.sm (17,14 KiB) scaricato 1517 volta(e).

#25 Pubblicato: 22/12/2023 13:24:37

Valery Ochkov

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Old good Euler. With units.

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1 utenti hanno apprezzato questo post

Martin Kraska 23/12/2023 01:11:00

#26 Pubblicato: 23/12/2023 01:11:01

Martin Kraska

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Three examples: the napkin calculation of "Nine Days of One Year", a single-stage and a two-stage rocket with parameters such that humans could survive the flight (limited acceleration).
The first section of the pdf is based on Valery's text posted earlier. It also includes some tasks for the reader.

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Rocket.pdf (421,58 KiB) scaricato 1062 volta(e).

Technische Mechanik mit SMath Studio: https://link.springer.com/book/10.1007/978-3-658-50592-9

#27 Pubblicato: 23/12/2023 04:46:41

Valery Ochkov

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#28 Pubblicato: 23/12/2023 06:16:12

Martin Kraska

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Whether m(t) is P or P+m[2 after engine cut-off depends on whether you get rid of the structure of the second stage or not. As long as we don't consider any subsequent maneuvers, the difference has no influence. If you do nothing, then payload and empty second stage will orbit side by side, separated or not.

Technische Mechanik mit SMath Studio: https://link.springer.com/book/10.1007/978-3-658-50592-9

#29 Pubblicato: 23/12/2023 15:03:09

Valery Ochkov

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Whether m(t) is P or P+m[2 after engine cut-off depends on whether you get rid of the structure of the second stage or not. As long as we don't consider any subsequent maneuvers, the difference has no influence. If you do nothing, then payload and empty second stage will orbit side by side, separated or not.

In Russia we say - punctual as a German!

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Error by ODEs solution - Help please - Messaggi