Engineering

Hi guys, I am looking to calculate the moment of inertia (J) and viscous friction (B) for a prototype motor connected to a fan load. The motor is powered with a constant voltage 3 phase supply and a torque sensor is connected in-between the motor and fan (figure 1). The torque sensor can give transient data of both torque and speed. figure 1: I have not tested the fan, but research seems to indicate the fan torque-speed curve will follow a quadratic curve like the one shown below. figure 2: I am assuming the bearing friction should have a fairly constant value B, however, the air resistance will cause an effective B that is dependent on the speed. By a…

This topic preplexes me, and it's kind of out of my knowlage range, due to the fact that im a social hermit. Will we ever find out why and over time do they release info if it was planned, like 70 years from now? Sorry typo in the title * how and why the tt fell

I like programming in Pascal as hobby, and I'm interested in trying something new so micro chips caught my attention. Can You please explain me what they are capable of? Is micro chips programming an expensive hobby or a cheap one? Thank You

Hello! I'm a Mechanical Engineering student and I have a work with my classmate about mechanical engineering applied in rockets, so I wonder what are the best topics to talk about it: projecting the rocket aerodynamics? The rocket engine? History of rockets? We are first working in the abstract, so I need a general idea of this subject (an introduction). Ps: I'm not a lazy guy, I just want to know some opinions of users that know about this subject as an orientation. Thank you very much!

im a junior in high school and i attend this school that specializes in the sciences, mathematics, and engineering subjects...im nearing my senior year which means that i have to start thinkin up ideas for my senior project...i take electrical engineering classes and our instructor wants us to create a project that includes a hardware and software component, preferably using the pic microcontroller... so...the bottom line is...do any of u have any ideas for me and my partner? lol so far we've thought of a radio controlled pen which would be used for school purposes...it would be used during a test or something so when the professor calls time up, then he/she woul…

I like to see and know how the remote controlled pen project turned out and details. I'm doing same project. Any help would be greatful.

So the first figure is the instantaneous power P1(t) =V12*I1 of a balanced 3 phase delta load. How would I determine the average power and power factor of the load? I assume the average power is just the mean of P1(t) or the mean of abs(P1(t)) ? Assume I also have access to P2(t) =V23*I2 and P3(t) =V31*I3 as defined below.

I dont know if this topic is placed in the rigth category, but if not please redirect it I am student in geotechinal engineering at Aarhus University and I am doing an experiment where I apply vertical load to a slope in granular soil. The experiment is made in a 1.6m x 1.6m concrete box and I am interested in measuring the movement of the soil particles during excecution of the experiment. I was thinking about tagging some of the particles and then tracking them with some kind of tracking device (radio active e.g), but I have no idea if that is possible. A more simple way is much appreciated too, such as painting some of the particles and measure the placement o…

Hello everybody! 3D printing spreads out as a means to obtain parts without the shape, production volume, delays constraints of machining: https://en.wikipedia.org/wiki/3D_printing Among several processes, the older stereolithography still makes the most detailed parts https://en.wikipedia.org/wiki/Stereolithography and here I propose methods to make it faster (or less slow). Stereolithography produces a part as successive layers from a bath of a prepolymer that hardens by light. The part sinks by a small amount like 0.1mm, a wiper defines an accurate thickness of liquid, and UV light hardens it where the solid shall be, by mirrors steering the beam of a laser. Success…

I'm trying to figure out if it is possible to create a building 10 acres long and wide and 10+ stories tall? It is very important I get accurate information please.

I don't know a lot about electrical engineering but I'm trying to design a simple circuit system. Lets say I have a source generating electricity in a circuit and say just as a random number 30 amps from one second of electrical current are stored in a capacitor. How would I then release that electrical energy more slowly to power a small light at 10 amps a second for 3 seconds?

So I work in the oil & gas field. My job is running a variety of tools in the well on a braided cable with an insulted copper core that can perform a variety of tasks. We've been debating this for a while now and I'm wondering if anyone can give me the scientific theory for why I'm right (or wrong!) The wireline has a breaking strength of +/- 10,000lbs of pulling force. If (as illustrated in the poorly drawn picture below) one of our tools is stuck in the well, how much force is being applied to the wireline at the top pulley (words circles with arrows pointing to it) and the line going from the top pulley to the stuck tool (words also circled). Any help would be tre…

I'm a mathemetician trying to test out a theory of mine. I have never taken any physics before, so i need help from the physicist and the engineers here. How much force/energy/work is required to lift a 2000lb car off the ground? What is that transalted into newtons and into rpms?

Hey, guys. I need your help and advice on something. Me and my guide were planning to pursue a research paper on the HCCI engine (Homogeneous Charge Compression Ignition), which was supposed to be an experimental paper. The problem is we are unable to find the testing rig in the country itself. So now, we are planning on pursuing different alternatives. One of them is using Matlab for analysis, simulating the engine conditions and obtaining results. Other is modifying the diesel engine and using it to perform as the HCCI engine. What do you guys think? Any suggestions? Any other ideas?

With the technology we have today supersonic travel is way way way way too costly for the public. Could a supersonic plane running on biofuel, hydrogen, electric or say solar replace jet fuels to lower the cost of supersonic travel? Making supersonic travel possible? I know they are doing research and experiments now on electric planes and solar planes now but it still not ready for a replacement of jet fuel. May be in 10 years from now they will start phasing out jet fuel for biofuel, hydrogen, electric or solar? And we will have supersonic planes.

Hi guys. I have managed to get a good grasp of the IM thanks to some very cleaver and friendly gentleman on this forum, but I am now struggling to understand the RSM operation. I have an understanding of magnetic reluctance and how the motor is designed to have different reluctance depending on the orientation, but I am still unsure how this creates torque. I have an idea on how the torque is generated at synchronous speed, but I think it may be flawed. The figures below show my logic. Basically I know that flux does like not to change, so if the motor falls behind the stater field, it functions as a magnet for a brief period of time. This magnet is attracted …

Hi! I'm researching disposable static mixers at the University of Wisconsin-Madison. I was wondering where a mixer with a reduced L/D ratio would be the most useful. Currently, the research is in disposable mixing components such as those used in 2 part resins, epoxies and polyurethanes. These mixtures are then used in construction, marine, and automotive manufacturing applications. Where would a shorter mixer (that reduces product waste) be the most beneficial? In what application within these industries? Where else might I look for an answer to this? Thanks a ton! Brian

I hear alot of issues with electric cars is that they lack long distance traveling ( less than or equal to an ICE), or that charging them can be expensive. Is there a design that charges the car as it moves? For instance, a generator attached to one of the wheels that isn't connected to the drive train. This way as the car moves, the battery is constantly being recharged, like an alternator. -Of course by my luck this already exists and I look like a moron now ~EE

Engineering: How To NOT Build Bridges.. More info http://www.rtlnieuws.nl/nieuws/binnenland/terugblik-dit-gebeurde-alphen-aan-den-rijn Good that nobody died.

Road reflectors, light posts, rebar, threaded rods and various screen tubing need to be anchored in concrete with epoxy. I'm trying to get an estimate of how many holes need to be drilled/mile of new road. Thanks!

Dear All I have a project to produce two injection-molded parts. One molded part was made of ABS. The other one was made of PP. These two parts contacted with each other. The ABS part rotated on the PP part (10 rpm). So, the ABS part abraded the PP part. After 500 times of rotation, the result was that the PP got serious wear. The rockwell hardness: ABS: R-Scale 110 PP : R-Scale 80 If I use an ABS material with Rockwell Hardness at R-scale 100, does the PP part get less wear? Thank you.

Hello everybody! In June 2015, the European Patent Office (EPO) awarded their European Inventor Award. Franz Amtmann and Philippe Maugars winned the "industrial" category for their contribution to the near-field communication (NFC) technology, and while the EPO's wording was still careful, in the Press it naturally became "they invented the NFC"... So here is my own compilation of some contributors I know of, where logically I'm not forgotten. ---------- Nikola Tesla made experiments and had big ambitions. He may have been the first (or not) as he had invented many more machines based on induction and RF. Though, the uses of electricity then, essentially f…

I know that traveling up a space elevator slows the earth slightly and traveling down it speeds it up slightly. I also know that this is a miniscule amount. I am curious though if this effect continues past the geosynchronous orbit point if the load were to continue on the cable towards the counter weight? Also would any type of engine exerting a force on any point of the elevator also change the speed of rotation or would it simply destroy the elevator?

I need some help intuiting the input vs output characteristic for the NMOS depletion load circuit. For example, I can see why the driver should start off saturated then move towards non-sat as Vinput increases, but I cannot see why the load should start off non-sat. Additionally, if we assume the output resistances to be large, then the driver switches to non-sat and the load switches to sat at the exact input voltage (which doesn't seem obvious to me). I have attached some figures to illustrate the problem.

Two related cases involving multiple coils around a cylindrical barrel. Two separate goals (but probably related math): Coils are activated in sequence to accelerate a magnetic object down the bore. Think 'Gauss-pistol'. Coils are activated (possibly with polarity reversal at/as needed) to smoothly accelerate a magnetic plunger down the bore -- and maybe cushion it when nearing the ends. When it reaches one end, the process is reversed to accelerate it back to the other end. Think 'rectilinear actuator'. Physical feedback (e.g., optical interruption) about the object's position in the bore is my first preference, since fancy harmonic circuits aren't my forte. I'm ba…