Modelling Definition and 250 Threads

Sorry for such an easy question LOL.. So.. I need a bit of help, I was thinking of modelling a ram air intake on a car. But it seems like I'm not educated enough.. What I know is: the car goes with 100 km/h speed, the engine consumes 1800 liters of air / minute, and the intake at...

I need a book to study the theory for turbulent modeling for external flow. So far I used Fox & McDonald for fluid dynamics, it has turbulent modeling for pipe flow. I learned to simulate it in fluent & learned a lot more in its tutorials(though i didn't know the theory part:biggrin::redface:)...

Could someone please help me urgently? The problem is: 130 micrograms of thyroxine is needed in her bloodstream. Her doctor prescribed one 100 microgram ,thyroxine tablet to be taken every day. If the half-time of thyroxine is 6.7 days, either justify that the uptake of thyroxine by the body...

I'm having a bit of trouble working out the cosine function for the data I have on tide charts. Homework Statement I need to put the data provided into the cosine function y=acos(nx-b)+c Morning average high tide: 5.137 metres Morning average low tide: 1.29 metres Afternoon average high...

I am aware of the very valuable analysis skills physics teaches. A physics major may not be possible for me so with your experience with physics or electrical engineering, would you say you learn how to model physical systems better with electrical engineering or with mechanical engineering? It...

hey everyone, this is for a school project, I'm wondering what would be the best for building a model to represent the Earth's magnetic field. it has to be 3D so what would be the best way to represent this? Also it has to do a demonstration what would be a good way of demonstrating the Earth's...

Hi everybody. This is my first post in this forum. I am working with COMSOL MULTIPHYSICS and I am trying to model a laboratory burner (Meker burner) heating a copper disc placed above the burner. I am modelling the burner as a boundary setting of heat flux entering the domain. I have obtained a...

Homework Statement A particle of mass m moves along the positive x-axis with a potential energy given by V(x)=C+4/x^2+x^2 where C is a postive constant. Calulate the equilibrium position X0 of the particle. Homework Equations None. The Attempt at a Solution I realize...

Homework Statement I need some help with all of the questions in the attatchment but would love it if you could provide some help with the first question please. Homework Equations In the file. The Attempt at a Solution Dont be silly, I don't have a clue. If I could do it I...

Hi all! OK, hopefully this will be a very quick question. Basically, I want to know how to model a vacuum tube (both triode and pentode) in terms of creating a dynamic system model. For example, if were to look at the voltage in an inductor as a function of time, I would employ the relation...

OK, I have an assessment task to create a 3D model of SOME of Einstein's thought experiments involving trains and mirrors, and present it to the class. Therefore a minimum of 2 thought experiments. The task is unique (ie each student is required to model a different part of the course), and I'm...

University project which involves modelling the acceleration of a car from 0-60mph given certain variables. I am looking for help with how torque and power relate to the driving force of the car, I think i have every thing else covered but any help will be greatfully recieved. The model will be...

Hello My friends , I want to deal with a nozzle in an unsteady flow , what methodology should I use in your opinion to solve it using Computational Fluid Dynamics and using Fluent software . Thanks in advance

Due to complications I have with drawing and uploading pics at the moment, I'll simply describe the model instead of posting a pic; it's a cantilever beam (ignore the cross section and modulus of elasticity given in the pic, and the force P) of length L = 1, the coordinate axis x is along the...

The Problem: Consider a species in which no individuals live beyond 3 years. Divide the population into four age groups labelled by n = 0,1,2 and 3. Assume that only the second and third groups can reproduce. For each group n let bn denote the birthrate and d_n the death rate. Find a matrix A...

hi guys, i am an 11th grade student who loves physics and i have been doing lots of advanced problems from books like irodov,etc. I recently came across something called mathmatical modelling via differential equations. And my teacher once mentioned that u can solve most of problems of...

Hi, I'm trying to model air resistance to try and predict where destroyer gun shells will land on an online computer game. I've tried quite a few things which have met with some success but are not accurate enough. I think however this time I might have found a better solution in the form of...

The other day I met a up and coming fashion designer from florida. We got talking and found we had a lot in common, I showed him some of the outfits I had designed and made and he loved them! (he also showed me his designs) He then offered me a free trip to florida to be a runway model for the...

A logistic function has formula U(n+1)=rUn This models the growth in the fish population from year n to year n+1. If you now decided to harvest H fish, your equation looks like this: U(n+1)=rUn-H Now, they want me to find the maximum H for which the population stays constant (growth factor...

Hi guys, If there's anyone out there who has knowledge in this area, I'm seeking to find out how to model memory consolidation using neural networks. I was thinking of using a Hopfield network to train another Hopfield network. The first network would represent the hippocampus, and the...

Hello all, i have a small dilema. I am interested in computer simulation for engineering and design purposes. I am currently evaluating as many of the available ( and free or accessible to joe public ) applications/software systems for engineering simulations and dynamics, with the aim of...

I had recently stumbled upon a computer program that can automatically add missing hydrogen atoms to protein structures from files from the protein data bank. (due to the hydrogen atom having only 1 electron, hence making its electron density too low to be detected by X-ray crystallography...

I am doing my final year project on the modelling of a dc zonal electric distribution system for a navy shipboard to analyse its stability. I am planning to use Matlab for the modelling and similation. I have a few problems on the way ... I am not able to model a simple buck converter (Ship...

5 A particle moves horizontally in a straight line according to the rule x(t) = t^3 − 5t^2 + 3t − 5, 0 ≤ t ≤ 7 where x metres is its displacement to the right of the origin at time t seconds. a What is the initial position of the particle? b After how many seconds does the particle pass...

4 The height, x metres, of a diver above a swimming pool at time t seconds after he has bounced from the diving board can be modeled by the function x(t)= 3- 3t (3t^2/2) a How long, in seconds, after he has bounced from the diving board does the diver reach his maximum height? b What is the...

Hi, When modelling something such as a capacitor using a method like Boundary Element Analysis (BEM) then this may lead you to a visual model i.e it shows you the charge across the plates or the density of the fringing field, rather than a method which uses a pure mathematics such as Gauss'...

Hi, I get my grad school decision in about 2 weeks.:cry: I'm having a problem deciding between 2 fields that I would love to do a research project in. Both involve Computational/Simulations Science [Computer Science(computability and 3D engine development) & Mathematics]. The 1st is...

HELP: Mathematical Modelling Question Hi Given X_1 \ldots X_n be stochastic independent variables with the distribution functions F_X_{1}, \ldots ,F_X_{n} . U = min(X_1 \ldots X_n) and V = min(X_1 \ldots X_n). F_{U} and F_{V} for U and V, and let F_{U,V} be simultaneously distribution...

What is the best way to solve for friction, and in particular, heat generated due to friction (Qfric), analytically? The first presumption is that is a sliding contact (the domain can be either 2D or 3D, it doesn't really matter yet at this point). One model is to have two rectangles...

i found this video on youtube.com. Basically it is a modelling of how the Earth will be affected when a meteor hit Earth. Heres the link: http://youtube.com/watch?v=3JHdYBet_4Q I wonder, is this modelling close to a realistic modelling? P/s: It is in japanese.

Hey, So, In a question about finding volume in a dome we were Given that V = pi.k(k^2/r - k^2/3r^3 - r/8) And K = m/2pi.p.t Firstly we are asked to obtain an expression for the value of r that maximises the volume of air and rearrange to obtain an equation of the form ar^4 + br^2 + c =...

Hello, All, I hope I am not out of line here, this is the only cosmology forum I could find to ask a few questions... I am considering developing a piece of software that can produce a 3D model of cataloged objects, by querying something like NED or SIMBAD, and generating this as a real...

Hi a few questions i want to check my answers for here, 3. Write down an expression, evaluate the constant of proportionality, and answer the question. [Remember to work in SI units. Simplify answers to 1 d.p. only.] (a) The annual cost (C) of running a business is partly constant and...

hello. i am university student and currently doing infrared static Earth sensor modelling. Here, i need some help in making my project. is there anyone who knows about modelling the static Earth sensor? it is really a great help if you can tell me all the steps in making the model..

I'm dong a question that involves a sink. The aim is to determine the dimensions of the sink (width and length) which will provide the greated cross-sectional area by modelling using an equation. Here's the catch: you are only allowed a sheet of stainless steel that it 60cm wide and a 5cm...

Hiya, I have been looking at a problem, and just can’t get my head round the right way to tackle it. I have a whole heap of data for an airline showing the taxy duration of each of their flights (this is the time taken to go from the gate to actual lift off). As I see it, there are 3...

have solved the lane - emden eqn numerically for scaled radius, and the derivative of scaled pressure with respect of scaled radius, are given the eqn of state, n, and mass, how would i go about working out the central density and the radius? thanks

does anyone have any knowledge on fire modelling?

Hi, I am trying to model the temperature profile of the inside of a tent, with a view to introducing a fan which can suck outside air, to inside the tent, to cool it down on a hot sunny summer morning. I thought I would start by just trying to model the interior of a tent in these...

hi , As a part of my project, i am modelling air resistance using a differential equation. For the write up, i need to discuss what assumptions i am making. I have the rest of the coursework sorted out. I have a few idea . Air resistance is presumed to be consistent. ( i.e no...

I have modelling a mechanical element in ANSYS. Those who have used it will know what I am talking about. I want to obtain the reaction forces at the supports (Fx,Fy,Fz,Mx,My,Mz). So I go to List Reaction forces command window and Ansys gives me a list of nodes and its single reaction: PRINT...

What would be the best way to come up with a new model for friction based on my experimental results? I have been finding the angle at which a block slides, or topples when the angle it is inclined at is increased. This has been done with blocks that are of different heights (towers of...

Hi, Recently I have started with learning mathematical system modelling. I seems very interesting so I am looking for books to learn more. Could anyone recommend some good books or some web address about doing mathematical models for real life systems (engineering, economics, human...

hi I want know, what is parrot algorithem which is used to find the relectivity profile, how it is related to box modelling! can you explain? cheers Manesh

Although I don't want to be given a straight answer to this question, I would really appreciated some help to point me in the right direction. The amount of a drug in the body follows the equation y=De^(-kt) , where D is the initial dosage, k=(ln2)/6.7 , and t is the time in days since the...

i have a wave function and i would like to see how it acts after it receives my first input. I would like to see its ups and downs and its different color when its amplitude is changed after the function value reaches a certain point. For example let say y=Asin(x+p). Would you please tell me...

I'm trying to teach myself some of the early basics of stellar modelling and hope to write some code to calculate conditions within the star Assuming a constant and homogenous composition and simplified calculations of pressure equation of state and opacity. Simplified assumption of...

Hi I was wondering if anyone knew of any good tutorials on modelling control systems - I have to convert a RCL circuit to a control system - i understand things like how to express components mathmatically but am confused as to steps I should take to make sure I do a thorough model? Any...

For those of you familiar with numerical modelling of various phenomena, you will know about work like the various discretisation schemes, stability/gradient limiters for high order schemes and so on. The most broad sweeping improvement to the field of numerical modelling would ultimately be...

I want to model an extremely simplified explosion in a little program I have. All I want to do is accurately model the movement of a single object affected by this explosion in a void. Here's how I'm thinking about things so far. I'd appreciate it if people could tell me whether I'm on the...