Engineering

The Morandi Viaduct which suffered a spectacular collapse in 2018 has been rebuilt and is about to reopen. https://www.bbc.co.uk/news/world-europe-53628580 There was an earlier thread about the collapse, but I can't find it ATM.

Hello dear friends! Stretching stiffens polymers a lot, making wonder fibres of banal bulk materials. It brings LCP from 10GPa to 170GPa. Highly stretched polyethylene makes wonder ropes of Dyneema, Spectra and competitors. Stretching *3, easy with a polymer, strengthens much a stripe from a polyethylene shopping bag. Companies that stretch metal (for piano wire and others) could adapt to thicker polymer too. Or polymer manufacturers themselves could stretch or extrude the material cold or lukewarm, so mechanical engineers have stiff strong bulk polymers, lighter and easier to machine without fibre reinforcement. The transverse properties may drop. Rol…

I have developed a totally innovative "Fully Hydraulic Motor" which I submitted to an automotive company and local university lot of years ago. Not any feedback received on it so I post it here for if someone in the world could be interested. I´m not interested in the production patent rights, may be just to be mentioned as the original author of the concept. It is based on an electronical concept applied in hydraulics. Here is the two pages pdf I wrote to present it: https://drive.google.com/file/d/1J_LnpLlhbFTY-wPqEOk2G5z7545BB674/view?usp=sharing Any comment is welcome.

Hi all. In winter time, aluminium window frames form condensation from any humidity inside the dwelling as cold is easily conducted from the outside exposed metal surfaces, puddling on sills and staining paint, probably causing rot in underlying wood. Is there any treatment/coating that is usually applied to aluminium frames to avoid that damage ? The glass does not condense humidity, just the highly conductive Al frames do. 🙁

Hi Recently my company has wanted to conduct waste testing to determine the composition of the wastes in concentration or wt%. This testing will help us to determine whether there are any excess chemicals in the feed of the process, which in turn can also be used to identify the effective composition of chemicals in the feed needed to produce the least waste or zero waste. However, we can't provide any testing parameter to the laboratory because we don't know what will present in the waste and too little information is given for the feed of the process. Besides, by referring to the material safety data sheet (MSDS) and certificate of analysis (COA) of each chemical u…

I am fascinated by robotic technology, so I thought maybe one or another would post here some examples like the 2 below, Petman and a bird.

As some of you might know, I have designed a crewed interstellar spacecraft that I call Solar One. Basically, large flexible mirrors placed near the Sun would propel a one-mile light sail with a 4–crew spacecraft of 300 tons. To decelerate, an on-board compact fusion reactor would power a photon rocket placed at the front of the spacecraft that would 1) help decelerate and 2) ionize space hydrogen for the nuclear reactor. A Bussard scoop also placed at the front of the spacecraft would 1) collect those protons (ionized hydrogen) and 2) decelerate the spacecraft. Solar One would achieve an average of 22% the speed of light, w…

Hi. Vomited by the sea :

I have most of deionized water system that I am looking for a good home. Everything works, it is just missing an ion exchange tank service associated with it. The pump is 240V 3Phase. Anyone looking to set up a medium sized DI water system?

Hello nice people! Some objects moving against a gas or liquid, especially wind turbines, aeroplanes and water craft, include a vortex generator at their wing, fuselage or hull, usually before the body recesses. The vortices avoid or ease the "flow separation", so a wing lifts at higher angles of attack, and at fuselages, the drag decreases despite the vortices. wikipedia Heat exchangers can use them too. The common explanations are as undetailed as "turbulent flows separate later" or "introduce energy in the boundary layer". Consistently, usual designs of vortex generators are quite crude, as depicted below or with small variations. While quite a…

Please excuse me as i am trying to simplify this as best as possible without having to draw a picture 😃 I questioned earlier about perpetual motion and it led me to idea no2. You have two cylinders. One filled with water and one in a vacuum. You have a container that is denser than air but still buoyant. The container passes through the water filled cylinder pulling a cable that turns a generator. Once it reaches the top it passes into the cylinder with the vacuum and falls to the bottom still pulling the cable. Would this create a positive energy output?

Ideas 💡 for a perpetual motion generator that harnesses gravity to create a positive energy output 🤔 EDIT: lesson learnt, always research your idea before starting a topic about it 😅 even with positive and negative mass chasing each other, its impossible to create a positive energy output.

Hello.I am a aspiring engineer or physicist or computer scientist.While in high school(8th grade I am 13) I have had multiple chats with individuals about the topic of FUTURE LIKE SPACE TRAVEL.I don't mean flying saucers but spacecrafts that use magnetic levitation to leave earth's atmosphere , or Negative mass built spacecraft .I was wondering what are the possibilites of such technologies.

Hi everyone ! In shops, one remaining Covid contamination path is money. An answer is to allege that money doesn't host the virus, I read that. Or we can try to tackle the problem. UV light is known to destroy virusses, including Sars-Cov2. UV LED are available for near-ultraviolet Hg wavelengths, compact, reliable, efficient. This could irradiate the money between the cashier's and the customer's hands, in both directions. The rest is mechanical design, still imprecise. The apparatus must stop the UV from exiting but irradiate both sides of banknotes and coins. Both users could introduce the money at the top, say between a pair motorised soft rolls, a…

Is it possible to decrease the systematic error to zero,approximately zero the ideal state,if we consume that the systematic error occurs because of the temperature difference in the room where we are meausiring,the instruments are getting older when we are using all the time.For example if we are at a room which we can nearly keep the temperature difference constant,and we use only new bought instruments,can the systematic error become to zero.Is that possible to explain theoretically and practically?

I'm trying to pre-bake dry a developed photoresist. Generally what temperatures can soft photoresists handle? can a soft-baked photoresist handle warm water? Thanks

My company has an old Hitachi V212 oscilloscope. I found two online manuals one saying I needed the AT-10AQ probe and another saying the AT-10AJ probe. In our office I only found two AT-10AR probes, one working one broken. Could someone potentially elaborate the differences? Are there ways I can use different probes if i can identify the differences, and account for them in my results? Also Ive seen a lot of 1x/10x probe nomenclature, does that refer to the "10" in the probe name, and is that reflective of the Gain? Thanks

I am using manual rotameters to mix concentrate and water in-line. do I need to be concerned if the pressures of each stream are different? How can i be sure that backflow does not occur if my water line is higher pressure than my concentrate. what kind of range of mixing can I achieve? Can i mix 0.1mL concentrate with 100mL water if the pressures are the same? how much will variation in house water pressure effect the ultimate accuracy? Thanks

Washing machines squander electricity to heat water, dishwashers too. That much: (0.4m)3 = 64kg water from +15°C to +40°C is 6.7MJ=1.9kWh, in two passes 3.7kWh. Heat losses during the process make it worse. At variable 0.3€/kWh it costs 1.1€, just once a week is 170€ in 3 years, ouch. To +90°C it's 30MJ, in two passes 11kWh and 3.3€. Every second week costs 260€ in 3 years. Blistering barnacles! We can fill the machine completely, and when possible wash in a single pass less warm, to save electricity, washing powder and water. I've just bought 6 bed sheets which the saved electricity will pay in 3 years, better than a savings account. But what can technology do?…

There are a host of inexpensive HD antennas for sale that seem to promise reception that seems beyond possible. I have always understood the broadcast T.V. signals are pretty much line-of-sight or about 35 miles before a tower is needed to get above the curvature of the earth. I recently watched a comercial that claimed 100 miles reception with one of those non-elevated, mount indoor, H.D. antennas. Two questions: 1) Is that 100 mile claim an outright lie? 2) If not an outright lie, what specific electronic technology would make 100 mile reception possible? If you choose to answer my questions, please list your qualifications (to weed-out pre…

Hi. There is the claims of what is better or not; the copper, the iridium, the iron, the platinum ones... Are the expensive metals used in tiny amounts only on the spark eroding prone tips or is there a larger component using such ? I would suspect the industry would just save the $ and barely coat/plate only the critical surfaces. What do you know ?

Hello everyone, I am very curious and unsure, today I watched a documentary about Hydrogen and the earlier attempts of a Hydrogen Economy. I am really fascinated! But I don't understand why the Hydrogen Economy always failed. Already in 1874 wrote Jules Verne that hydrogen will replace coal in the future, 100 years later in 1980, after the Chernobyl catastrophe the Hydrogen Economy had a new climax and it failed again, and now researchers shout out again : The Hydrogen Economy start now! - What changed? - Why can the Hydrogen Economy now be successful?

Does anyone know how small a nuclear fission explosion can be for nuclear pulse propulsion? It seems that you would want a "tiny bomb" with the smallest mass possible. You want to give enough push to your pusher plate but you don't want the tiny bombs to add too much weight to your space probe. The smallest I could find is the Davy Crocket: "The M-28 or M-29 Davy Crockett Weapon System was .... one of the smallest nuclear weapon systems ever built, with a yield between 10 and 20 tons TNT equivalent [1/1000th Hiroshima]." https://en.wikipedia.org/wiki/Davy_Crockett_(nuclear_device) ONE of the smallest? What are the others? By now there must be smaller …

Hello, I am an engineering student. I have a question for you. Let us consider, we have an electric motor and it is being supplied the electric current. Thus it is converting the electrical energy into mechanical energy and we are getting the rotational motion at the end of the shaft. Now, what if we connect another motor(to be specific a generator) to the end of the shaft and it is further connected to store the energy in batteries, is it possible to convert the energy completely and store it? maybe not due to the core losses in both motors. But, what if we attach a set of gears at the shaft such that, the speed of rotation of the second motor is greater than t…

Is it possible to reverse play a sound file? Sound file formats viz .wav,.mp3,.aac etc. Do the methods will vary for different sound file formats? Thanks & Regards, Prashant S Akerkar