All Questions

0
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0answers
10 views

Recommended torque

I am working on an assembly where I have various screws, mainly metal on metal fastening. Where can I find a realiable source for recommended torque settings based on screw size, screw material and ...
1
vote
0answers
8 views

Strength of Plastic Underwater Domes with various thicknesses

I'm currently researching the strength of domes underwater and I went down the rabithole of material science. The basics of this research (or though experiment) is to bring a dome filled with air to ...
0
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0answers
21 views

Removing a post [duplicate]

I have a question about removing a post that is either supporting a beam or the post was there because there was a wall on both sides of my living. please take a look at the photo. There's a house ...
0
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0answers
16 views

Research based bridge project? [on hold]

I am a fourth year civil engineering student at IOE pulchowk, Nepal. In our syllabus one practical based curriculum called Project Engineering has been added. I, along with 5 friends, are interested ...
0
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0answers
26 views

Help. I'm not in engineering. I want ideas to explain the behavior of a tube when I apply a rotation force

When a patient gets intubated to connect to a ventilator, the tube is taped to the outside of the mouth. As we move the patient, the circuit connected to that tube is usually held to avoid pulling. ...
2
votes
0answers
26 views

How to resolve the interruptions in the screw pump operation due to air trap?

In one of my application, there is a requirement to dispense the concrete paste at the required rate continuously. some technical details of the application given below Dispense rate 5-50 LPM ...
0
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0answers
15 views

Confused about information on a state transition table

I'm working with a State Transition table with a variable I can't identify. Here's the table: I'm pretty sure "a" is the present state. "b" is the next state and Sx and Sx+ are the inputs. ...
1
vote
1answer
29 views

Is there is vanadium-free high speed steels?

Vanadium is present in all high speed steel grades. unfortunately vanadium not only very expensive but is also a will known cytotoxic metal. some workers get severe persistent cough lasts for months ...
1
vote
1answer
32 views

Thevenin equivalent impedance in laplace domain

I can't understand why $Z_{th}$ doesn't include $3\ \Omega$ resistance.
2
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2answers
38 views

Will circulating air within a sealed ductwork system cause it to implode?

Referring to the pasted in ductwork diagram, if an inline ventilation fan with a high CFM airflow was used to circulate air within a sealed ductwork system, would the fast moving airflow result in a ...
0
votes
1answer
22 views

Generic category of PBT thermoplastic

I'm an EE, but I'm working on a project at work where I need to venture into materials science & chemistry. My question is, does thermoplastic, Polybutylene terephthalate (PBT), fall into any of ...
0
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0answers
14 views

AutoCAD Boundary Trim with Multiple Boundaries?

So for a particular task I need to trim and remove cells from a boundary with an action macro I can accomplish this fairly simply using the following procedure. Create unit cell (closed polylines) ...
0
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0answers
32 views

“Freeze”/Mold paper in a certain bent position [on hold]

I have a piece of paper (lets says its a A4) and I bent it in a certain way (like a skateboard ramp, I'm holding the ends and the middle kind of falls forming this "ramp" model), but now I need a way ...
0
votes
1answer
35 views

Air Cools As It Expands

What is the degree of cooling caused by air flowing from smaller diameter into a large diameter? How much does air cool as it expands? If the air inlet was the biggest hole on the right and the ...
-1
votes
2answers
46 views

CSTR properties - What happens to conversion of products if I change the reactor size?

For example, initially this reactor is having a 2nd order reaction of $-ra=kaCa^2$ and it has a fractional conversion of 50% in a CSTR. I replace it with something 1/6 as large. What happens to the ...
0
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0answers
18 views

Please help solve this problem! [on hold]

Fluid with mdot = 0.025 kg/s and Tm,i = 25oC is flowing through a long metal cylindrical tube where the diameter is 0.032 m and the length is 2 m. The surface of the tube is heated with a heat flux of ...
1
vote
1answer
34 views

Phase response of a continuous transfer function

Let $\omega_0 \in \mathbb{R}$ and $\omega_0 > 0$. Be $G(s)$ a transfer function defined as: $$G(s)=\frac{1-\frac{s}{\omega_0}}{1+\frac{s}{\omega_0}}$$ We're interested into evaluating its phase ...
-1
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0answers
25 views

how to determine the transfer function for block diagram which is given below [on hold]

how to determine the transfer function for block diagram which is given below
0
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0answers
24 views

Designing a piston pump for windpump

I am designing a savonius type wind pump for low wind speeds(avg speed = 2.7 m/s), with these speeds and rotor area of about 2 m2. Acc. to my calculations, I am getting a volume flow rate of ...
0
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0answers
25 views

which type of casting will give higher cooling rate, casting in thin water-cooled copper mold or casting in thick copper die?

It is will known that increasing cooling of a metal casting will lead to finer micro-structure which mean higher mechanical properties. If I have 2 molds one is thick copper die ,& second is just ...
-1
votes
0answers
24 views

Could you power a machine with bamboo growth? [on hold]

Apparently bamboo grows so fast you can almost see it. Using some clever gearing system could you harness this movement to power a machine? Perhaps a digital clock. For example attaching a lever to ...
0
votes
1answer
19 views

addition of non paralle shearing forces and stresses

I would like to ask for help regarding the summation of non parallel shearing forces acting on an elastic body. In the image force F (Left to right direction,in yellow) acts on the top horizontal ...
0
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0answers
20 views

How to “isolate” thermal resistors when doing a 1D transient conduction question?

I have a system that I can model using a thermal circuit analysis. In this system, I have a hot gas, and thus a convective resistance $R_{convection}$, that heats the surface of material "A" . Then I ...
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0answers
15 views

Yield stress and tangent modulus of Silicon and Al2O3

I searched a lot for the values of yield stress and tangent modulus of Silicon and $\text{Al}_2\text{O}_3$ on the Internet. But I was not successful. Is there any help to find them?
0
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0answers
17 views

Derivation of Stiffness Matrix for an Orthotropic Material

Consider the figure attached. Assuming that the coordinate system is placed at the centre of the cube and plane x-y is the plane of material symmetry, $x_i$ represents the position vector of $i$th ...
1
vote
1answer
27 views

What is relief amount in grooving operation

Can somebody please explain what relief amount at the end of cut in a grooving operation on lathe is?
0
votes
1answer
24 views

What is the solar window (solar altitude angle range) of Bangalore? [on hold]

What is the solar altitude at Bangalore at solar noon during summer solstice, March equinox, Winter solstice and September equinox? In other words, What is the solar window (solar altitude angle range)...
3
votes
1answer
34 views

How are solar panels at equator placed?

Are solar panels placed horizontally at the equators since the solar altitude (solar window) changes direction from north to south?
1
vote
2answers
63 views

Mass of exhaust or Mass or rocket?

This is from Stephen Hawking's latest book; Brief Answers to the Big Questions. The speed at which we can send a rocket is governed by two things, the speed of the exhaust and the fraction of its ...
-2
votes
1answer
37 views

In what way the object-oriented methodology model an information system? [on hold]

Answer briefly how the object-oriented methodology transforms an information system. I really do not know how to answer that question. I know what is an information system ("System capable of ...
1
vote
0answers
21 views

Linear actuator calculations

I'm building a motorized standing desk and am looking into what to use for the linear actuators. I'm targeting a stroke of 450mm and a lifting force of 100kg. I found some Linear Actuator on ebay that ...
0
votes
1answer
10 views

CANbus simulator for win or linux [on hold]

Im trying to learn how CANbus works and how you connect to CAN bus and sen amd get messages. Since we work with CAN at work I would really like to be able to "program" a network using CAN. However I ...
0
votes
0answers
9 views

EES model library [closed]

I was wondering if there is a website or resource to find code repositories for different processes or energy systems, I have to model a lots of cycles and technologies in my project, some of them had ...
0
votes
1answer
25 views

Peltier Element - Segregation of the Hot/Cold

Referring to this diagram: How does the height of the P and N components affect heat or cold generated on this thermoelectric element? The idea I keep having is that it seems like the hot and cold ...
0
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0answers
19 views

How do you calculate effective green time when lane groups are in multiple phases?

How do you calculate the effective green time when lane groups are in multiple phases? I am trying to calculate the effective green time for each lane group. Do you use the formula $$g_i = \left(\...
0
votes
0answers
13 views

Technologies of Recognition of physical objects [closed]

In which fields should I read to gain understanding of technologies regarding recognition of physical objects ?
0
votes
1answer
45 views

derivation of Young's modulus experiment formula

In an experiment used to find the Young's modulus of a steel bar, the formula for change in height is given as follows: $$\delta_x=\frac{Fx^2}{6EI}(3L-x)$$ $$I=\frac{bh^3}{12}$$ where: $δ$- the ...
0
votes
1answer
30 views

Calculations of compound gears?

Recently I've been scratching my head over an assignment, and I have trouble understanding a couple of the parts. The issue I have is with the overall calculations, since we've just started on ...
2
votes
2answers
55 views

Why two identical beams without being pinned together will share half of the bending moments?

As shown above, two identical rectangular beams are placed and NO pinned together. I know each beam has its own neutral surface but why they carry half of the bending moments? I thought the bending ...
0
votes
0answers
29 views

How can I make a door automatically lock and unlock at specific times of day? [closed]

I need to create a "cheap and simple" method of locking and unlocking a door at specific times of day.Its an open ended problem and solution from electric, electronic, mechanical or a combined ...
1
vote
1answer
15 views

Variables Relating to Atmospheric Water Generation

I am interested in discovering a method to relate air flow to temperature reduction efficiency. The purpose of this is in application to atmospheric water generation. The apparatus will involve a ...
0
votes
0answers
27 views

Civil Engineering and Environmental Civil Engineering? [closed]

What is the difference in studying Civil Engineering and Environmental Civil Engineering? And Do your jobs prospects differ after gaining the degree?
1
vote
0answers
30 views

Calculating the lifting force $F_{Kab}$ with SolidWorks – according to VDI 2230

I’m not sure if my procedure to simulate the lifting force $F_{Kab}$ is correct. So I illustrate my way how to get the lifting force $F_{Kab}$ using SolidWorks and the simulation tool. I hope you can ...
0
votes
1answer
26 views

What is the purpose of the isolated subpanel terminal of a solar inverter?

In a grid-connected (utility-interactive) battery-based PV system, what is the purpose of the 'Isolated Subpanel' terminal of the inverter? EDIT: Found this descriptive image and hence answered the ...
0
votes
0answers
10 views

Finding the W in piston-cylinder system

I am tried to solve this question by using, $Q-W=\Delta U$, where the kinetic or potential energy differences are neglected. I changed the equation to $W=Q-\Delta U$ and also to $W=\Delta H-\Delta U$....
2
votes
1answer
48 views

Validation protocols

Question from a validation beginner in the pharmaceutical industry. What are the common approaches to start writing validation protocols (esp. IQ, OQ, PQ)? What are the common approaches to start ...
1
vote
2answers
75 views

What does a stalled hydraulic pump mean?

What does it mean when a pump stalls? I could not find a useful explanation with the search terms pump stalling and hydraulic pump stalling. I'm trying to understand what Elon's tweet means. Maybe an ...
1
vote
2answers
54 views

Analizing Vibrations Influence on Dynamic Weighing

I have a very sensitive scale used for dynamic weighing (by dynamic I mean that the scale and load cells are actually beneath a belt conveyor that actively weight product when it´s being transported ...
1
vote
2answers
287 views

How did the RBMK control rod design cause an increase in reactivity when moved downwards?

I have been trying to understand a particular aspect of the Chernobyl accident - the role of the graphite displacers on the end of the control rods. The basic story is that the graphite displacers ...
1
vote
1answer
32 views

How to introduce the CONSTITUTIVE equation into structure mechanics [closed]

Suppose I have stress and strain relationship and it can be simplified to the equation $\sigma=Function(\epsilon)$. This is the CONSTITUTIVE equation of the material I want to do research. Assume ...

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