Questions tagged [modeling]
Use this tag for questions about numerical or analytical modeling and simulation of engineered systems.
207
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The application of a Fluid (air) cooler on 20mm product, equations for temperature, moisture content and relative humidity (maybe modelling)
I currently have a fluid bed cooler which is cooling fine powder (around 20mm) product which enters upto 80 °C (minimum 40 °C) and leaves at a maximum of 25 °C. The mass flow rate is about 1200 kg/h. ...
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Effect of bracing on a music instrument top - is FEM modal analysis enough to predict this?
I'm currently building a music instrument (string instrument), and I am at the step where one applies certain braces to the soundboard. Since I actually don't know how the bracing will affect the ...
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Transfer function to get linear velocity from a dc motor system
So I have to create a control system simulation from scratch for the following scenario. For a bicycle-like system, there is a motor attached directly to the rear wheel. From here, the goal of the ...
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Modeling air bearing flow as porous medium
I want to model the flow through a cylindrical air bearing such as the New Way Flat round air bearing, so that I can play around with modifying parameters (porous and fluid medium type and geometry) ...
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Design? Or something else
When we develop a new technical device (after creating its general concept), we want to implement it. But before we implement it, we must design it. And for this we go through some stages (the list is ...
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Heat Transfer from variable profile truncated fin in Maple
I have a truncated, triangular fin with a rectangular base (width/thickness "w").
The profile is variable, described by: y=-((y0-yL)/L)*x)+y0
The tip is insulated, wall is a constant ...
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What is the difference between mathematical and process/control degrees of freedom?
Taking mathematical DOF as:
$$ DOF= N_{vars}-N_{eqs} $$
How would process, or control degrees of freedom be defined as?
Thanks!
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Python Control library step_info returning nan for all parameters
I am running the following code:
...
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Running a Dynamic Model as Steady State with Time Varying Inputs
I am attempting to run a dynamic model of a waste heat recovery system (Brayton Cycle with intercooling) on IDAES but I keep getting errors on initilization seemingly no matter what I do. My work ...
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How to solve emptying of ditch
Please let me explain this situation, I have a ditch which is being filled with rain, the ditch is emptied and can also act as storage if inflow>outflow.
$ Q_{in}-Q_{out}=\frac{dV}{dt} $
$ Q_{in}=\...
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User Code Start - End Structure In Simulink Coder Frameworks
Is there a user code start - end structure in simulink coder frameworks? I am using embedded coder. I am modifying the code generated by the Simulink. But If I change something on the model and re-...
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Building CAD Models for simulations and 3D Printing
Is there a tool that allows you to make changes to models so that they can be used for both 3D printing and static simulations in SolidWorks. For example, I want to have a part printed and to deal ...
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41
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What are the applications of spontaneous synchronization to engineering?
I came across the amazing phenomena of spontaneous synchronization and how it can be modelled by the Kuramoto Model. I am curious as to spontaneous synchronization has its relevance in engineering.
...
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Why stopping at the first derivative in conservation equations?
Oftentimes we, as engineers, have to write energy/mass/momentum balances to derive the governing equations for a quantity $\phi(x,t)$ of a physical system. One of many derivations of such balances ...
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What is the difference between activity and event in "simulation"?
I am studying about components of a system. The subject is "system simulation/simulation modeling/discrete event system simulation". This is related to electrical, electronics, computer ...
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How can I eliminate oscillations in Sim-Routing for HydroCAD?
I am currently attempting to model a stormwater system that has a high likelihood of backflow because the proposed basins are interconnected and there are no intervening structures which would impede ...
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I applied acceleration at the base of model in Abaqus. I ran the model and got the output, the acceleration at the base doesn't match the input. Why?
I am modeling an earthquake in Abaqus. I applied acceleration in the horizontal direction at the base of my model. I plotted the input acceleration. I ran the model and got the acceleration at the ...
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Is there an estimate for the packing density of boxed household items/furniture?
A bit of a silly question, but I'm not sure where else to ask.
I've been trying to estimate if it's cost effective to move certain household belongings over a long distance, given the price I could ...
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Viscoelastic modeling, what is wrong with my Boltzmann Superposition integral?
In a similar setup to many Micro-Pipette Aspiration experiments, I have a ramp-and-hold aspiration, and calculate the resulting elevation using the Boltzmann hereditary integral.
My aim is to fit the ...
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Simple simulation model of water boiling in a pot?
I want to investigate boiling processes (in the kitchen) by simulation. To this end I assume there is a pot ($m_\mathrm{pot}, C_\mathrm{pot}, T_\mathrm{pot}$) with some water inside ($m_\mathrm{water},...
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Simulinks modeling of 2-loop circuit containing LRC elements
I have been attempting to model the following circuit using KVL and Simulinks:
Applying KVL generated these coupled differential equations:
$$
0 = -V + \frac{q_1}{c_1} + R ( \frac{dq_1}{dt} - \frac{...
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332
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Are these section views correct Autodesk inventor
So I used AutoDesk inventor and created this machine part for the purpose of exercise , But it is preferred to not to hatch ribs in my course so is there a way to make it look like image (5 and 6) ?
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Autodesk inventor create rib feature failed
It's been kind of painful to create a rib I'm new to inventor while I was trying to create a rib symmetric about the YZ Plane this error keeps popping up
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How to draw hidden rib in Autodesk Inventor
I drew the outer hollowed body and the cylinder on 2 separate parts but I can't figure out how to draw this rib so that it is passes through the centre of the cylinder, a video of a similar example ...
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Tranfer function of non-self regulating process
This system is non-self regulating process with mathematical model :
dh/dt = (fi-fo)/C
where
fi = flow input,
fo = flow output,
C = tank capacity or volume tank.
I want make tranfer function of this ...
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147
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Mathematical model of an hydraulic jack
How to find a mathematical model of this hydraulic jack system?
I'm confused about the part when the piston extender, check valve 1 opens and check valve 2 closes, then liquid from the bottom tank ...
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How does one deal with indeterminacy in modeling the motion of vehicles with multiple wheels? (Dynamics Question)
Consider a vehicle with four wheels and suspension (coil and dampers) rolling over an arbitrary surface. What would be the magnitude (not direction) of the normal force on each wheel? Is there a ...
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I’m having trouble converting this orthogonal shape to isometric, I’m only a beginner and would really appreciate some help [closed]
Orthogonal to isometric shape, I need help with this as I’m only a beginner, please help me.
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Sliding-mode control is a model-based technique?
The sliding mode control can be considered a model-based control? In my opinion yes since takes the information of the mathematical model of the system to be controlled handling with possible ...
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Workbench: Explain the difference between the case with bonded contact and the case with the frictional coefficient of 0.01
Explain the difference between the case 1 with bonded contact (top image) and the case 2 (bottom image) with the frictional coefficient of 0.01
For both cases, the top plate has displacement and the ...
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Solidworks - how to make a groove on a double curvature surface
Today, as I was making -for another post - the following part
Although, I managed to use a couple of ways to do the above (revolve a sketch, and b) using swept cut) I wondered how would I make ...
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Unstable System. Error Trying to model the Red Bull Stratosphere Free Fall
I tried to model a problem months ago and still I can't solve, I don't want forget this problem so I would like to share what I tried and if you know what is happening with my graph.
This is the ...
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Examples of model-based control techniques
I am trying to find out the differences between the model-based control approach and the data-driven one.
Surely the main difference is the latter's independence from the information of the ...
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Nominal model and Mathematical model of a real plant [closed]
What is the difference between nominal model and mathematical model of a real plant?
I am interested in understanding the difference since I want to understand why in some cases is not the best idea ...
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a model of a solid using trusses to approximate internal stresses?
my question is as follows: could the stresses on a solid body be aproximated with a discrete model based on trusses?, this is, that the result yielded by the analysis of the truss structure will ...
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Modelling of Ball and Beam System
I'm trying to model a basic ball and beam system using Euler-Lagrange Equation. My system looks something like this
I have come up with this final Euler-Lagrange Equation:
Where JB is the ball's ...
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Linear Nastran model not converging
I am running a SOL 101 linear statics FEA. If I fix down the whole geometry it converges. But anything less than around 90% fix down and it will sit there crunching away at the numbers forever. This ...
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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
$\...
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How to design an enclosure around the load cell (Beam type)?
Hardware and Electronics Used: Arduino UNO, HX711 ADC Load cell amplifier, Load Cell (2Kg);
Currently, I am working on a project which requires me to put load cell along with the other circuitry in an ...
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Modeling torque as surface pressure
Consider a rod with a length of 150 [mm] and a diameter of 44 [mm]. At the left boundary the rod is fixed to a wall. At the right end a torque of 1000 [N m] is applied. The remaining boundaries are ...
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transfer function with constants
I have the following differential equation and I need to obtain the transfer function of Z / P but there are constants so I cannot factor to obtain the relationship, how could I obtain the transfer ...
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propeller air mass flow equation
I am trying to model a hovercraft and I need to obtain an air inlet flow ratio in (kg / s) of a propeller based on its dimensions (it can be the radius) and speed, is there an equation like that? ...
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How do I read this schematic drawing notation for a drill hole?
It's for an NX part. I can't figure out the depths and such. I just know the placement of the 4 holes and that the diameters are 10 mm each.
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When can the thermal and mechanical energies of a fluid control volume be considered separately?
For a fixed control volume of a fluid, the conservation of energy equation is typically written as something like
$$\dot{Q} - \dot{W} = \frac{\text{d}}{\text{d}t}\iiint_{CV} \left( \hat{u} + \frac12 V^...
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Are there examples of spring-mass-damper system that exhibit increasing growth in an unstable way
Simply, are there examples of spring-mass-damper systems that exhibit unbounded behavior or at least increasing behavior for a period of time. I am trying to do some vibrations research, but I am ...
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How are circular dependencies dealt with inside MBSE?
How are circular dependencies (best) managed inside of MBSE environments? Let's say I have two properties that are linked to each other / they are linked to properties that affect each other.
How is ...
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How to model this real-world system to define transfer function for stability?
The system shown is an off-axis drive system that rotates the platform to 60° via a substantially-sized NEMA 34 stepper motor. The axial force required by the stepper/ballscrew assembly has already ...
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Optimal control of the gradient type PDE
I recently encountered the following optimal control problem.
The purpose of the system is to find the parameter $x$ at which the maximum or minimum of the function $f$ a is reached. $x$ is unknown to ...
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Trouble with an actuator on a Robotics SolidWorks design. Any ideas why?
I am in the process of developing a robotics design on SolidWorks.
The goal of this design is to tilt a platform using 2 actuators.
My design utilizes 2 indirect actuators that are separately powered ...
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Is there any formula to model the effective Young's Modulus of a fluid-filled spherical shell?
I am creating composites of a host epoxy and filler particles which are thin-walled fluid-filled shells. Using the Halpin-Tsai equations, for example, I can predict the bulk composite Young's modulus ...
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