Recent content by strive

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    The best way to liquefy Ammonia

    Ok, for the processes read this: http://www.sciencedirect.com/science/article/pii/S1876610216000539 For manufacturers/price you are looking for 'industrial refridgeration units'. This page is the first i found: http://www.ashirwadco2.com/industrial-refrigeration-unit.html
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    Fatigue of a Rotor: Predicting Life Expectancy with Variable Cyclic Stresses

    It is a small impeller/turbine. Imagine it powering an acrobatic plane - in turns it can experience up to 6 g's, and surges in the airflow. Roots of the blades - where the blades are molded together with the hub - experience very high stresses. I need to determine how long these blades will...
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    The best way to liquefy Ammonia

    Check Linde's Process and Claude's Process. You will find patents and blueprints/schematics for both on google. Expansion - when you increase the volume of a gas while keeping its mass the same its temperature decreases. Return the process for increassing the temperature. Most modern...
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    Desired Accelaration to Torque

    Well, i am missing some data in your explanation, but if you don't like sharing the details, that's allright. We'll find a way around it. What do you mean with 'driveline dynamic'? If you are worried about using your non-dt formula, don't worry, just use a sufficiently small timestep in your...
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    Desired Accelaration to Torque

    What do you mean by dynamic? If you want to calculate Force/Power at a given instant in time your equation is ok. If you wish to plot Force/power over a given time period for a constant acceleration value, you need to either use 'dt' or do the calculation numerically (iteration per iteration).
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    The best way to liquefy Ammonia

    You said you allready have NH3 at -33°C, i presumed you meant at some high altitude (or polar region) which means you just need to keep the gass there. If you are in STP conditions, you would need a well made vacuum flask for insulation, and you can keep it cool by circulating liquefied gas at...
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    The best way to liquefy Ammonia

    Pressurization. You increase the gass pressure, at which point gas temperature also rizes - and hence keeps NH3 in gaseous state. You let the gass cool down and when the pressure/temperature ratio falls to the right ratio the NH3 liquefies.
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    Fatigue of a Rotor: Predicting Life Expectancy with Variable Cyclic Stresses

    I have a fast rotating rotor spinning over 2 axis (over its main axis and over an external axis - the two axis are perpendicular to each other). Easiest to imagine this is like a windturbine yawing as it follows the wind direction.Each of the two rotations obviously causes a distinct centripetal...
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    What are the options for boundary conditions in ANSYS WB structural analysis?

    Static support on one end - this will give propper reaction forces. Note however that you migh get singularities on the edges of that face. That is normal hence you can ignore them.
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    Hybrid Combustion-Nuclear Electric Rocket

    In hall thrusters, as far as I understand, they are pulled out by the electron stream. And due to their much higher mass they produce the bulk of the thrust. I wonder if this would also be the case in a combined chemical/electrical engine, or would the interaction between ionized and non-ionized...
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    Hybrid Combustion-Nuclear Electric Rocket

    Ok, let’s break it down: In this case (actually in many cases) efficiency is misleading. Let’s take a look at this from mass/thrust ratio. Primary mass (discounting dry engine mass for simplicity) in chemical propulsion systems is fuel, in electric engines the primary mass is the sum of fuel...
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    Can I Find an Analytical Solution for Spherical Trilateration?

    Beautiful! By using the equations from ’The Intersection of a Cone and a Plane' paper and the plane intersection method, I think I can now make this work. The problem with using the transformations to and from the Cartesian coordinate system is in my initial measurement errors, as they are...
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    Can I Find an Analytical Solution for Spherical Trilateration?

    Yes, I can calculate their radius, but initially I can only measure the angular separation between two antipodal points of the circle (the base of the angle is the large sphere). The radius of the large sphere is not accurately known as it is virtual (imaginary is perhaps a better term). Of...
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    Can I Find an Analytical Solution for Spherical Trilateration?

    Yes that is correct. I have tried to use equations for great circles and for small circles, but to no avail (although my math might be the reason, because the numerical solution works in this way). I haven’t thought of trying with planes. But how do i define a straight plane in the spherical...
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    Can I Find an Analytical Solution for Spherical Trilateration?

    Hi I am looking for an equation of intersection of 3 circles or 3 spheres, on the surface of the fourth (central) sphere, in a spherical coordinate circle. This should really be just a simple trilateration problem. I know this is usually done by transforming the spherical coordinate system to...
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