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Some of the mentionable low-thrust propulsion methods are, ionic propulsion, Hall-effect thruster and solar-sail systems. The electrostatic ion thruster uses high-voltage electrodes to accelerate ions with electrostatic forces, and achieve a specific impulse within the range of 4000-8000s.
The best performance (in terms of thrust efficiency and power-to-thrust ratio) can be obtained using high atomic weight alkali metals, such as cesium (Cs, 133 amu) and rubidium (Rb, 85.5 amu). These propellants have a low ionization potential (3.87 eV for Cs and 4.16 eV for Rb), low melting point (28.7 °C for Cs and 38.9 °C for Rb) and very ...
In fluid dynamics, stream thrust averaging is a process used to convert three-dimensional flow through a duct into one-dimensional uniform flow. It makes the assumptions that the flow is mixed adiabatically and without friction. However, due to the mixing process, there is a net increase in the entropy of the system.
The particular take-off distance required may be shorter than the available runway length. In this case a lower thrust may be used. Lower thrust settings increase engine life and reduce maintenance costs. The take-off thrust available from a civil engine is a constant value up to a particular ambient temperature.
The bottom quarter or so of the wheel travels underwater. Rotation of the paddle wheel produces thrust, forward or backward as required. More advanced paddle wheel designs have featured feathering methods that keep each paddle blade oriented closer to vertical while it is in the water; this increases efficiency. The upper part of a paddle wheel ...
This method however takes much longer due to the low thrust. [6] For the case of orbital transfer between non-coplanar orbits, the change-of-plane thrust must be made at the point where the orbital planes intersect (the "node"). As the objective is to change the direction of the velocity vector by an angle equal to the angle between the planes ...
The required take-off thrust was 14,500 lb which would normally be set by advancing the thrust levers to give an EPR reading of 2.04. Due to EPR probe icing the value set, i.e. 2.04, was erroneous and actually equivalent to 1.70 which gave an actual thrust of only 10,750 lb.
Multiple supply vehicles are required to satisfy the ISS's 7,000 kg annual average propellant need. The then-current plan for six Progress M1 spacecraft per year met that need. The Propulsion Module would hold 9808 kg fuel. Progress M holds 1100 kg; Progress M1 holds 1950 kg. ESA ATV holds 4,000 kg. The cancelled U.S. Interim Control Module ...