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As to the nature of that drive, one thing was now certain, even though all else was mystery. There were no jets of gas, no beams of ions or plasma thrusting Rama into its new orbit. No one put it better than Sergeant-Professor Myron when he said, in shocked disbelief: 'There goes Newton's Third Law.'
для компенсации теплового расширения, которое в условиях вакуума достаточно сильно влияет на опытную установку
ЭТО НЕ БУДЕТ РАБОТАТЬ В КОСМОСЕ!
В своей статье «Принцип относительности и его следствия в современной физике» (1910) А. Эйнштейн детально объяснил, почему концепция светоносного эфира несовместима с принципом относительности.В общем, эфиристом Эйнштейн не был. А просто хотел перезаюзать термин
Позже, после создания общей теории относительности (ОТО), Эйнштейн предложил возобновить применение термина, изменив его смысл, а именно — понимать под эфиром физическое пространство ОТО. В отличие от светоносного эфира, физическое пространство не субстанционально (например, нельзя приписать точкам пространства собственное движение и самоидентичность), поэтому для пространства, в отличие от эфира Лоренца-Пуанкаре, не возникает трудностей с принципом относительности. Однако большинство физиков предпочло не возвращаться к использованию уже упразднённого термина.
О какой бы вы сумме ни подумали (говоря «дешевое»), можете смело приписать три-четыре нолика к ней
Вы слишком плохого мнения об учёных. Вы много с ними имели дел?
По собственному опыту скажу — творческих людей, готовых пересматривать взгляды под влиянием аргументов — много.
Сравните количество научных публикаций с адекватным обсуждением этого феномена с количеством материала, посвящённому восторженным крикам о том, чего только с этой штукой можно сделать.
The purpose of the test program was to investigate the EMDrive claims using improved apparatus and methods. To this end it was successful in that we identified experimental areas needing additional attention before any firm conclusions concerning the EMDrive claims could be made.
IV. Conclusion
We have built and tested an EMDrive using a commercial standard magnetron with a resonance frequency of 2.44 GHz and 700 W of power in setups similar to the ones used in the past in order to assess possible side effects and their claimed thrust values. Our thruster had a considerably smaller Q factor (around 50 for the first tests and 20 at the end) compared to others (10,000 – 100,000), however our test facilities had a higher sensitivity as well.
Our first tests were done with a knife-edge balance configuration and we assessed different isolation scenarios in order to see any thermal or electromagnetic influence. As expected, we noticed a large thermal effect that could be significantly reduced by thermal isolation and by blocking any air circulation inside our measurement box. We indeed found thrusts that changed with the orientation of the thruster and magnitudes in line with the theoretical predictions for our low Q factor. After turning off the power, the thrust values in the order of several hundred µN remained and slowly degraded after power shut-off. Considering that the EMDrive and especially the magnetron mounted on it can get hot, such a setup does not seem to be able to adequately measure precise thrusts.
We continued with testing on a torsion balance inside a vacuum chamber. Here we also found thrusts but quickly realized that there was a strong interaction with our magnetic damping system. Still we used this setup to test an EMDrive for the first time in high vacuum down to 4×10-6 mbar observing similar thrusts (although at somewhat lower power levels) ruling out any air influence in this configuration. After changing the position of the magnetron (outer position) and replacing the magnetic damping with oil fluid damping, surprisingly we could still observe thrusts that are indeed reversing with thruster orientation but with control runs in vertical direction producing similar
thrusts compared to the positive direction. However, negative thrusts were only observed with firing the thruster indeed in a negative direction. Running the magnetron also in this direction at lower voltages produced similar positive values as the vertical control experiment. The thrusts observed with the oil-damped torsion balance were close to the original prediction taking our small Q factor into account (around ± 20 µN for 700 W of microwave power – still an order of magnitude more effective than pure radiation thrust). We also observed that the thrust appeared not to go down to zero immediately after power is switched-off but rather noted a gradual decrease as if
the EMDrive was charged up and slowly reduced its thrust effect.
The nature of the thrusts observed is still unclear. Additional tests need to be carried out to study the magnetic interaction of the power feeding lines used for the liquid metal contacts. Our test campaign can not confirm or refute the claims of the EMDrive but intends to independently assess possible side-effects in the measurements methods used so far. Nevertheless, we do observe thrusts close to the magnitude of the actual predictions after eliminating many possible error sources that should warrant further investigation into the phenomena. Next steps include better magnetic shielding, further vacuum tests and improved EMDrive models with higher Q factors and electronics that allow tuning for optimal operation. As a worst case we may find how to effectively shield thrust balances from
magnetic fields.
the magnitude of the actual predictions
А вот это очень понятно откуда взялось.
совершенно не понятно откуда следует что это равно ресурсу реактивной массы, которой как-то будет оперировать EM Drive
To simulate the space pressure environment, the test rig is rolled into the test chamber. After sealing the chamber, the test facility vacuum pumps are used to reduce the environmental pressure down as far as 5x10E-6 Torr.
Two roughing pumps provide the vacuum required to lower the environment to approximately 10 Torr in less than 30 minutes. Then, two high-speed turbo pumps are used to complete the evacuation to 5x10E-6 Torr, which requires a few additional days. During this final evacuation, a large strip heater (mounted around most of the circumference of the cylindrical chamber) is used to heat the chamber interior sufficiently to emancipate volatile substances that typically coat the chamber interior walls whenever the chamber is at ambient pressure with the chamber door open. During test run data takes at vacuum, the turbo pumps continue to run to maintain the hard vacuum environment.
We have built a torsion balance for electric propulsion testing that can support 12 kg on a balance arm and features liquid metal power feeding (using Galinstan cups), magnetic and fluid damping. We use the attocube FPS laser interferometer with superior resolution and drift characteristics which results in sub nano-Newton thrust resolutions and very low drifts which makes it one of the best thrust balances available today.
The torsion balance is mounted inside a large vacuum chamber (1.5 m length and 0.9 m diameter) which sits on top of a Newport optical table to damp it from outside vibrations (see Fig. 6). In addition, rubber damping is used inside the vacuum chamber to further isolate the balance. The chamber is equipped with an Edwards XDS35i scroll pump and a Pfeiffer HiPace 2300 turbo pump (>2000 l/s) to achieve a base pressure in the 10-7 mbar range.
However, before changing damping, we tried to assess if air heating/buoyancy effects could still play a role as the signal followed the temperature decay from the magnetron. Therefore, we tested the large horizontal negative thrust direction in high vacuum by evacuating the chamber down to 4×10-6 mbar.
Минус 7 или единицы на 10^-8 это в каких единицах?
НАСА против EmDrive, раунд второй: и всё-таки он работает