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.

636 questions with no upvoted or accepted answers
Filter by
Sorted by
Tagged with
2
votes
0answers
592 views

How does Abaqus calculate reaction force?

I wrote a UEL for one element and compared to a reference UEL (FEM), where the results agreed satisfactorily, except the reaction force. The stress, strain, strain energy all were pretty accurate. I ...
2
votes
2answers
601 views

How Can You Calculate Force to Overcome Friction From an O-Ring Seal?

I essentially have a piston in a tube that is sealed with an O-Ring and actuated with a solenoid. The friction of the O-Ring however, is higher than estimated (guessed as far as I can tell) by the ...
2
votes
0answers
69 views

Mechanical engineering, Please help me finding the torque and answering other doubts too

Below I attached two BLDC motor commonly used for skate boards, I am confused with the calculation of stall torque for these two motors,What i need to know, What is the maximum weight lifting ...
2
votes
0answers
87 views

how do tilt-shift DSLR lenses and video projector lens shift lenses work?

For photography there are tilt-shift lenses. For video projectors there is lens shift lenses. With video projector lens shift I get perfect, undistorted video projected up to 100% above, below, left ...
2
votes
0answers
62 views

Efficient Gearing to Climb a Rope Vertically

I am trying to design a gearbox of sorts that would climb a rope from turning a gear (motor, handcrank, etc). The largest issue is that, while both the top and the bottom of the rope will be attached ...
2
votes
1answer
179 views

Anti-Squat Force Transmission

I’m trying to understand how anti-squat works in motorcycles and how the geometry plays a major role. I don’t understand, however, the reason why the force from the tires that is transmitted to the ...
2
votes
0answers
541 views

GD&T for Multiple Surfaces as Single Feature

I'm looking to get some collective agreement on a question that I have come across a few times now. When referring to features that are technically independent, what is the general consensus on ...
2
votes
0answers
27 views

Plot zero-pole from frequency response matrix

I've represented with Matlab a system with three degrees of freedom. I'm trying to plot a pole-zero map from my Frequency Response Matrix H(w) in the case of Damped-...
2
votes
1answer
204 views

How to make a cyclorotor?

I have looked for a way to make a cyclorotor mechanism which allows the blades to rock/rotate (in the picture below, its rocking I believe) to no avail. I am not able to find the required length of ...
2
votes
0answers
50 views

A Question of Coaxial Rotors and Lift

I'm only a HS physics student, so please bear with my lack of jargon. My question goes like this: In the scenario of two coaxial rotors spinning independently in two different directions, each with ...
2
votes
1answer
133 views

Equivalent Force: Hydraulic rams in H frame machine press

A 100ton H frame machine press can use 1x100 ton ram to exert this amount of force. Can 3x33 ton rams do the same job if they are applied to same area as the 100ton ram? Also in relation to a H ...
2
votes
0answers
57 views

Combining critical speeds for a shaft of variable cross-section

I am looking to determine the critical speed for a shaft with universal joints at each end, where the halves are joined by telescoping profile members. I can calculate the critical speed of each ...
2
votes
0answers
175 views

Worm Drive Calculation

I have this setup: -Pully with a mass attached. -Worm gear drive to lower the mass with a constant speed. (Section A-A) Now if we look at the cross-section A-A, we can see the worm gear drive: ...
2
votes
3answers
3k views

Deviation of Ideal Rankine Cycle from Actual Rankine Cycle

I'd been having difficulty with a problem from Cengel and Boles, Thermodynamics An engineering approach. The problem is about the deviated Rankine cycle from Idealised ones. The question I would like ...
2
votes
0answers
88 views

Why does a radiator valve require more torque after a few turns?

I'm automating a non-thermostatic household radiator valve, by replacing the knob with a DC motor and adding some support structure. You can see the system at work here: https://www.instagram.com/p/...
2
votes
0answers
590 views

IV drip/flow rate controller design

I have a question about intravenous flow rate controllers, which are controlled using microprocessors. For example: I want to control the IV flow rate, the flow is in range from 0 to 300. So, I just ...
2
votes
0answers
1k views

Stiffness of members in a bolted joint

I'm trying to calculate the safety factor against separation of members in a design that looks like this: I know how to find the bolt and cylinder stiffness, but I don't know how to find the ...
2
votes
0answers
577 views

Straight sided serration dimensioning

I have invented something and I need to have some external broaches made but I'm being asked for some dimensions I simply do not understand. I need 4 external broaches. They all have the same major ...
2
votes
0answers
68 views

What is “Yale Key, 10½ Section, change 900”

The specs say: Admittance shall be by means of a locked door and/or key operated switch, which in order to provide compatibility within Local Authorities, shall be a Yale Key, 10½ Section, ...
2
votes
0answers
24 views

Decission between several position switches and one continuos position signal for controling rotating conveyor

We plan a conveyor that will dump something into containers. A level gauge on the tip of the container will measure the heap below. The conveyor is placed on a turntable and will e rotated ...
2
votes
0answers
153 views

How big does hail need to be to damage auto body panels?

I am trying to determine under what conditions falling hail will dent automobile panels. For example, is it determined by the size of the hail, the speed of impact, force, energy, etc.? I know there ...
2
votes
0answers
67 views

problem in the calculation of pressure drop for an axial turbine

I am simulating an axial turbine. In this turbine, there are two domains. The first domain is the piping before and after the blade and the second domain contains the turbine blades. The domain ...
2
votes
0answers
56 views

Identifying coefficients to determine cutting speed for PA6 plastic

As part of a study at work, I have to calculate the cutting speed and feed rates for cutting plastic. I have found a formula for cutting speed calculation: $$v={{C_V*K}\over{T^m+t^{x_v}+s^{y_v}}}$$ ...
2
votes
0answers
81 views

How do I calculate the best mass for the highest linear speed?

I have a motor whose specifications say that its torque is 190g*cm. If I have the formula for the mass of the wheel vs radius, is there any way I can find the radius to get the best linear speed? The ...
2
votes
0answers
144 views

Problem in an axial turbine

I am simulating an known as , using CFX as a solver. This turbine have 8 blades((360/8)=45 deg=pitch angle). Due to the circumferential symmetry, only one eight of the annulus has been computed, ...
2
votes
0answers
975 views

Flow velocity in exhaust chimney - typical design value

I'm looking at a project where stationary CHP engines will be replaced, leaving as much of the infrastructure in place as possible. Current exhaust velocity in the chimney is ~42m/s and it will be a ...
2
votes
0answers
193 views

How do I make my balloon annotations circular instead of oval-shaped?

I'm getting oval balloons for my annotations instead of circular balloons even though I selected the circular setting. Is there any way to edit/revert this annotation to become a normal circle?
2
votes
0answers
571 views

Band Brake placed Perpendicular to the Diameter bisecting the Angle of Contact

I was asked the question: A band brake is installed on a drum rotating at 250rpm and a diameter of 900mm. The angle of contact is 1.5pi radians and one end of the brake band is fasted to a ...
2
votes
0answers
333 views

Accuracy of torque specs?

I am working on a project and I am defining the torque specs. I used the initial torque spec as a baseline and then went out on the floor and tested it using multiple torque wrenches. The components ...
2
votes
0answers
66 views

What is the load response of a threaded fastener?

Due to the fact that pipe flanges rely on bolts, and bolts rely on friction, it seems obvious to me that in deflecting to meet the load, the nut will immeasurably turn. So my question is - how much? ...
2
votes
0answers
298 views

Plain bearings (plastic) in backlash free joints

I need to design some backlash free rotational joints for slow and intermittent movements (device for human-computer interaction) for my uni project. Possibly loaded in any direction; the loads won't ...
2
votes
0answers
99 views

Mechanical device to simulate hinge axis external/off of part

Take a horizontal bar 10' pinned on the right end, so that there is a hinge point on the right end. Space requirements dictate that the bar must be cut in down to 5' (cut in middle and keep the left ...
2
votes
0answers
1k views

What data do I need to plot a BSFC map

I have an 4 stroke spark ignition engine simulator which takes user inputs and outputs performance data. I need rpm, torque and brake specific fuel consumption (bsfc) to plot the bsfc map. I am able ...
2
votes
0answers
90 views

Power system of the 10,000 year clock

I've heard that the 10,000 year clock will use multiple power sources (heat differential, mechanical weight, etc.), but how are they all integrated?
1
vote
2answers
40 views

How do pilots of Deep Sea Vehicles operate the control surfaces and thrusters from inside a pressure hull?

A Deep Sea Vehicle (DSV) like Trieste or Limiting Factor or now Fundouzhe have control thrusters, ballast that has to be dumped, and other equipment to operate the DSVs. But the pressure hull is a ...
1
vote
0answers
33 views

Magnetic Force - Point of Load

I am using a Magnet like this in an assembly and I am trying to calculate the torque in point P2 (see picture below) resulting from the attraction force F between my magnet and the steel part. As I ...
1
vote
0answers
23 views

Narrowing down injection moulding material selection

How do I narrow down specific values when selecting a plastic for injection moulding? My part is uniform in wall thickness and thins out where a hinge a present. Properties: Will not go under many ...
1
vote
0answers
14 views

Is it possible to have a reference pulse interpolator for a CNC machine with dc drive?

Is it possible to have a reference pulse interpolator for a CNC machine with a dc drive? it should work with alternating current drive but I am not sure about the direct current drive. please help me ...
1
vote
1answer
26 views

Linear motion with triangle profile

I am looking for a way to generate a linear motion with a triangle motion profile for my hobby project. The travel distance should be 6cm (so 12 cm for round-trip) with constant speed 1.2 m/s or ...
1
vote
0answers
16 views

Velocity and Acceleration Polygons for Mechanism

I need to determine the velocity and acceleration of point H using vector equations and drawing a polygon. Given data is shown. $\omega$2 is 5.8 rad/s and $\phi$2 is 120 degrees I know how I can draw ...
1
vote
1answer
65 views

Relation between links and pairs in Kinematic chain

I came across a equation for kinematic chain (for lower pairs only) : L = 2P-4 where L: Number of Links; P is the number of pairs how could this equation be derived ? EDIT: I tried putting values in ...
1
vote
0answers
30 views

Does anybody know where this calculation for the mass moment of inertia for an eighth of a circle comes from?

These attached photos describe flaps which are a portion of a circle and equations are attached as the mass moment of inertia, but there are no descriptions. I am using this for part of my research, ...
1
vote
0answers
33 views

Pump system with dynamic head

Given: A pump system is defined with dynamic head of 46 feet. The height between the static pressure gauge and the surface of the water is 9 feet. Assumptions: Friction losses between the tank and ...
1
vote
0answers
28 views

Shell Breathing Modes and Base Excitation

I have been reviewing "Vibration of Continuous System" by S. Rao as part of self-studying to help with work. I started reviewing the chapter regarding shells and noticed that shells have ...
1
vote
0answers
42 views

Optimizing flue gas temp for maple syrup evaporator

I have a simple maple syrup evaporator. Fuel is burned in a firebox located under 1mm stainless steel pans containing maple sap--which becomes syrup once enough water is evaporated. After passing ...
1
vote
0answers
37 views

Lowest temperature at which a spring powered mechanical wrist or pocket watch will stop operating

In the Wired article 9 Russian Adventurers Mysteriously Froze to Death. A New Theory Explains Why, it is stated that: Without body heat to keep it warm, in such cold weather—estimated to be –13 ...
1
vote
0answers
9 views

Finding the Shear Center for a Beam with 1 Axis of Symmetry

I am trying to solve this problem of finding the shear center for the given beam and I have found that e = 35.94 mm, however the solution that was shared with me, had the answer of 39.17 mm. My method ...
1
vote
0answers
23 views

Is there any way to focus the mechanical vibration or stress of an object?

I am looking for a way to focus the vibration of a metal sheet at a specific point on that sheet so that other points vibrate less. Just like light and lens. Is there any way to focus the mechanical ...
1
vote
0answers
24 views

Can concepts like “critical damping” or “resonant frequency” be applied to more complex systems than just a spring and damper in parallel?

I am trying to do some modeling analysis by representing materials with parallel systems of springs and dampers. In the simplest case with just one spring parallel to a damper, we have the traditional ...
1
vote
1answer
64 views

What exactly is Hooke's law defined for?

I used to think that Hooke's law was a relationship between how much a bar under uniaxial loading deformed and the internal force (per unit area) that developed within that bar. But this clearly isn't ...

1 2
3
4 5
13