Questions tagged [mechanical-engineering]

Questions within the problem domain of mechanical engineering. Mechanical Engineering can be a broad field; consider choosing more specific tags if they apply.

Filter by
Sorted by
Tagged with
1
vote
1answer
72 views

Is a no-moving-parts air pressure transformer possible?

Is it possible to construct a solid state fluid system (tubing, channels, chambers, nozzles, etc.) that can convert the energy from a low-pressure high-flow-rate air current into a high-pressure low-...
1
vote
0answers
48 views

What is a good approach on creating a custom robotics gearbox

I would like to put together a custom gearbox of the scale of around 50mmx30mmx30mm to fix a gadget that I am designing. My question is how should I approach producing this? Should I design components ...
2
votes
0answers
17 views

Book recommendation for hydrodynamics of bubbles, drops, and particles

I am wondering if someone could please recommend to me some references on the topic of hydrodynamics of bubbles, drops, and particles, preferably in the context of complex and bio fluids. I am ...
0
votes
0answers
23 views

Cargo box opening system below

I am currently trying to make a delivery drone similar to ones Amazon did. Basically the cargo box which carry the package must open to below in order to drop the package. What I want to do is exactly ...
1
vote
0answers
33 views

Trapezoidal screw usage on robot arm rods [closed]

I'd like to build toy on picture - uStepper/EEzy robot arm. I'm little bit afraid of plastic gears - backslash, weakness, noise... Do you think trapezoidal screw will perform better when I use them on ...
1
vote
2answers
37 views

Assuming identical hole perimeter, for which shape is the stress minimized?

I know that stress is concentrated in the fillets, but what about the average stress along the entire hole? We can choose a circle, an ellipse, or a square with fillets. For which shape would the ...
1
vote
1answer
41 views

Need to make brackets for an AC on a truck

I have an old Uhaul that I'm turning into an rv. I'm putting the exterior unit of a ductless mini split AC on the "mother's attic" portion of the truck box directly above the windshield. ...
1
vote
0answers
21 views

Is it possible to Plot Damping Characteristic of a Gas Strut using Universal Tensile Machine(UTM)?

My aim is to use UTM to plot a Force vs Displacement plot which would demonstrate the damping characteristic of the gas strut. There is one existing research related to what I'm trying to achieve ...
1
vote
1answer
75 views

Why would anyone "pull the stem out and stop the wristwatch at night or when not wearing it" in the context of mechanical watches?

I read this the other day while discussing mechanical pocket and wrist watches: Plus it is common practice to pull the stem out and stop the wristwatch at night or when not wearing it. You then have ...
1
vote
0answers
48 views

Strange old smithing machine, what is it purpose?

Is anyone familiar with such thing? I suppose that is something used in forge. I don't have better photos, but "steering wheel" was placed on shaft with small gear and this small gear is ...
1
vote
0answers
21 views

Is NPSHr dependant on temperature?

I know that net positive suction head available depends on temperature since viscosity, density and vapour pressure depends on temperature but how about NPSHr? We know that the vapour pressure depends ...
1
vote
0answers
37 views

Any books or websites that anyone would recommend [closed]

I am a secondary/high school student to look into to help with mechanical engineering. I would like to do this for enrichment and as preparation for doing it at university. As well as this I am really ...
1
vote
1answer
25 views

Methods of altering the angle of a projectile launch tube

Given some desired release angle, could someone please suggest a way that a machine could alter the angle of a launch tube per feed back from an ultrasonic sensor (I've derived the relation between ...
0
votes
1answer
72 views

How can (many) mechanical watches keep track of the current day of the month when these vary so much over months and years?

Having dealt with dates and time in programming context for many years, I have realized what a nightmare our common calendars are, and how much they vary by the year/month/etc. Yet there are fully ...
3
votes
2answers
64 views

What are some technical problems with generating electricity using a gas turbine or combustible engine at a gas flaring site?

Numerous oil and gas exploration sites practice flaring for safety and disposal of unwanted low calorific gases. However, instead of just standalone burning the gas, why can't a gas turbine or ...
1
vote
0answers
35 views

What are some obstacles/issues you face while working in industry? [closed]

As part of a project incubator program at my university, I am trying to understand current specific issues, cumbersome processes, and obstacles facing engineering projects in industry. By pinpointing ...
1
vote
2answers
42 views

Will a motor with 1,16 Nm rotate a 50 mm gear moving about 12 kg

I'm not an expert in mechanics, so this is my question. I will buy the motor of the image below to move my door. In the motor shaft, there is a gear with 50 mm of diameter which will move the door. ...
1
vote
3answers
63 views

FEM degrees of freedom

Consider a "beam". In order to perform modal analysis using the finite element method, the beam is meshed with 2nd order hexa elements. The total count of nodes is 1280. The same beam can be ...
0
votes
0answers
9 views

Question regarding 2D simulation of orthogonal cutting operation on Abaqus

I'm trying to simulate an orthogonal cutting operation on Abaqus, I'm using Dynamic explicit analysis. I have defined my tool as Rigid analytical body and the workpiece is of Ti6Al4V, I have not ...
1
vote
2answers
189 views

How much deflection can/should I accept with Aluminum Extrusions?

I plan building things with aluminum extrusions. On this website I can calculate the deflection depending on the profile length and load. https://8020.net/deflection-calculator I.e. if I select a 20/...
1
vote
1answer
37 views

Static discharge inside a fuel tank

I am trying to build a sort of paramotor powered by hydrogen, my rough design looks like this; First dilute sulfuric acid is electrolyzed in a sealed aluminium container. Second, the valve is ...
0
votes
2answers
94 views

Can a beam be too short to experience bending stress?

The question in the title says it all. I've got a a configuration where I'm using a bolt to support a load. The way its set up, the bolt will have a very short cantilever on it. When I calculate the ...
1
vote
0answers
15 views

FEA Simulation of CHASSIS [closed]

What are the most accurate methods in static state for simulation of chassis wrt 4 cases: lateral bending, torsion, head on collision and a zero turn. The problem arises when it comes to applying the ...
1
vote
1answer
61 views

Dynamic model of a two-mass electric drive taking into account the Gear Ratio

Two-mass rotational system has the following form and is represented in following structural diagram. where $\tau_e$, $\omega_1$ and $J_m$ - motor torque, angular velocity and moment of inertia $\...
2
votes
1answer
31 views

How is the assumption that stress and strain are elastic everywhere is valid for STRESS-LIFE method for fatigue life calculation?

Stress life method is generally employed for high-cycle fatigue (HCF) applications. while HCF region is approximated by $\sigma=a(N)^b$ which gives a linear graph on log-log scale, for steels it ...
13
votes
1answer
1k views

How does a (pulley based) continuous variable transmission (CVT) work?

How does the (pulley based) CVT achieve the following? no requirement for a clutch fuel economy smooth gear transition
4
votes
3answers
157 views

How does my automatic car shift without complete temporary loss of acceleration

When my car shifts gears, the car's acceleration never goes to 0. I feel that there is constant torque to the wheels throughout the entire shift. How is this possible during a gear change? ...
0
votes
1answer
38 views

How to determine beam deflection with this unusual configuration (diagram attached)

So I've got a support system shown here in the attached image. Comparing configuration "A" to "B" it seems intuitive that "A" could support a larger load. The stubs are ...
0
votes
1answer
69 views

Sizing Linear Actuator to Rotate a Shaft

I have a horizontal arm attached to a shaft that I have calculated to require 151 in-lbs of torque. I would like to calculate the force required of a linear actuator to rotate the shaft via a 3.5"...
1
vote
0answers
20 views

Question about tensile test of model from research paper [closed]

In this paper they made a tensile force test on their four different models with four different pore size structure to show that pore size is not affecting on the tensile force. But it seems that they ...
1
vote
1answer
47 views

Why is the sum of binormal forces equal to zero?

I've read in Hibbeler Dynamics, page 131, that when considering a coordinate system with normal and tangential axes, the sum of binormal forces equals zero. I don't understand why this is true, maybe ...
2
votes
1answer
37 views

How to calculate mass needed for mounting electrodynamic vibration shaker?

I need to mount an electrodynamic shaker to the floor, I need to find the mass of the concrete under a T plate so as to stabilize the shaker. It has a max force of 6000-8000lb, 200 “g” shock, 3in ...
2
votes
4answers
117 views

Does constant velocity means no force applied?

If there is a body moving with a constant velocity of $1000m/s$ and it’s mass =$ 10kg$. Then , how is it possible that the force applied by this body$ = 0 N $since it will definitely make an object in ...
1
vote
0answers
31 views

what is the torque difference in single plate clutch disks and multidisk clutches? [closed]

I have a review question that I am not sure about the answer. The question goes like this: "In comparison to single plate clutches, multidisk clutches are associated to which of the below notions?...
1
vote
0answers
34 views

Jacobians and Manipulator Dynamics

This is a Stanford Manipulator I started off working on it by initially setting up the DH table Transformation Matrix and then Homogeneous Transformation Matrix I started finding the linear and ...
1
vote
3answers
90 views

Can we say that stress strain curve for a tensile test is function of strain rate and temperature?

I am currently studying about tensile test where it is saying that it is conducted at a constant strain rate. Also, it is said that it is conducted at a particular temperature. So can we say that ...
2
votes
0answers
23 views

Durability & air-tightness of PUR tube on barbed air port

I'd like to connect a long tube to a pressure sensor with a barbed port to measure air pressure (ambient air pressure +-10kPa). The sensor's barbed port has outer diameter 3mm. I'm choosing between ...
23
votes
5answers
5k views

Why exactly does a washer help distribute the stress around a bolt?

Usually the reason for having a washer under a bolt head is stated to be that it helps to evenly distribute the stress to the clamped material surface. But why is this? I would understand if the ...
2
votes
1answer
55 views

A Bonus homework question in Elementary Statics. A painter on a ladder put on a ledge [closed]

we have been asked about a bonus question in Basic Statics as mentioned below. I would be glad if someone help me with it. The question is: There is a painter which is going to work on a ladder as ...
1
vote
1answer
44 views

What does it mean by average kinetic energy of molecules as temperature?

We say kinetic of molecules as a function of temperature from the equipartition theorem. This means that more is the velocity or mass of the body , more the is the temperature. My Q is why does ...
3
votes
1answer
162 views

Modeling rigid body dynamics: Trouble with equations, encountering nonsense answers

Hi, I am working on modeling a simple rigid body dynamic system through a certain range of motion. Here is the picture of the system. I am trying to solve the system for the variables $x_1'', y_1'', ...
1
vote
1answer
48 views

Difficulty in understand the meaning of standard enthalpy of formation

Standard enthalpy of formation is when one mole of compound is formed from its constituent elements. Example : $H_2$(g) + $O_2$(g) —>$ H_2O$(L). But we don’t say the same for $CaO + CO_2$ —> $...
1
vote
2answers
58 views

How does the stiffness of semicircular beams connected in series increases?

I am working to reduce the deflection in a cantilever/ dive board at work.$300 mm(L) \times 30mm(B) \times 2 mm(H)$, i.e. it's a rectangular cross section currently. I can't change the material, or ...
1
vote
0answers
25 views

What is a safe and efficient temperature range for absorption chiller generators?

I've read that the role generators play in the absorption chiller cycle is to concentrate the salt solution so that the evaporator/absorber can maintain a vacuum by constant absorption of vapour ...
0
votes
1answer
92 views

In which bucket , should the water fill it up first?

Here , we have two water filters and buckets . Now , we know that as the water falls down , it’s speed increases because of acceleration due to gravity. Let us say I started both the filters and once ...
1
vote
1answer
102 views

Why does the ball detach from the surface of cup?

Here, let’s say I have a tea cup. In that cup , let us say there is a ball inside the cup which is temporarily fixed to the surface of cup. Now , this ball is fixed very loose but strong enough that ...
1
vote
1answer
55 views

Angular Velocity And Flow Rate Relationship Of Turbine

I was designing a turbine to be utilized in order to measure the flow rate of a river system. I can measure the angular velocity of the shaft by utilizing a magnet and hall sensor, however, in order ...
0
votes
2answers
167 views

Calculating the von mises stress in a 3D beam when given stresses and moments on both ends

I want to calculate the von mises stress in a given structural member. I want to generate a von-mises plot from this data. The forces are according to the local coordinate system of the beam. Also, I ...
3
votes
1answer
69 views

Industrial recycling of mirrors

I learned recently that mirror is mostly manufactured by pouring thin metal coating (i.e alumunium) on top of a substrate surface (i.e glass), Due to the nature of this composition it cannot be easily ...
0
votes
1answer
33 views

Calculating the load on the end of a beam

We ordered a really nice light for our dinner table and ordered a special "lightswing" seperatly. The light that we ordered however is heavier than the 'lightswing' is rated for. Please see ...

1 2 3
4
5
67