This is a model simulating a two-dimensional random walk in two variants, one by using a digital angle (in 90 degrees increments) and one using an analog angle between zero and 2*pi. This type of model (similar to the walk of a very drunk man) pertains very well to numerically solving Monte Carlo diffusion type problems. It is a brute force model using… Read More... "A 2D Random Walk Model – the “drunk man” animation"

This section is dedicated to modeling physics in Excel 2003 standard.

## The Melting Snow Castle – a diffusion model application

This is an application to the previously derived 2D diffusion (heat transfer) model. The snow melting process is very similar to diffusion or heat transfer. Just open the model and hit “Start-Pause” to see for yourself. It is a 2003 model or earlier. I wasn’t able to run it in 2007 with animation but I’ve got some friends who managed to run… Read More... "The Melting Snow Castle – a diffusion model application"

## Building a Dynamic Two Dimensional Heat Transfer Model – part #2

This is the second half of the tutorial which shows how to build a basic animated 2D heat transfer model in Excel. [sociallocker][/sociallocker] Building a Dynamic Two Dimensional Heat Transfer Model – part #2 by George Lungu – This is the second half of a tutorial which shows how to build a basic dynamic heat conduction model of a square… Read More... "Building a Dynamic Two Dimensional Heat Transfer Model – part #2"

## Building a Dynamic Two Dimensional Heat Transfer Model – part #1

Here is the first part of a tutorial which shows how to build a two dimensional heat transfer model in Excel. The presentation shows how to partition a square plate in elementary elements on which the simplest form of the heat storage and heat transfer equations can be applied. The numerical form of the final temperature formula is derived . Building… Read More... "Building a Dynamic Two Dimensional Heat Transfer Model – part #1"

## A Basic 2D Animated Heat Transfer Model (a diffusion model too)

Here is a basic 2D heat transfer model. The first five worksheets model square plates of 30 x 30 elements. The last worksheet is the model of a 50 x 50 plate. You can modify the initial temperature by hand within the range C21:AF240. It is also a diffusion model. It uses the storage and transport equations derived in the previous tutorials.… Read More... "A Basic 2D Animated Heat Transfer Model (a diffusion model too)"

## Animated Heat Transfer Modeling for the Average Joe – part #4

This is the last tutorial of the series and it shows how to implement the previously derived formulas into a spreadsheet model. The spreadsheet formulas, the macros and charting of the dynamic data is explained. [sociallocker][/sociallocker] Animated heat transfer modeling for the average Joe – part #4 by George Lungu – This is the last section of the beginner series… Read More... "Animated Heat Transfer Modeling for the Average Joe – part #4"

## Animated Heat Transfer Modeling for the Average Joe – part #3

This section shows how to model heat transfer in a linear bar by dividing it in elementary sections in which the basic linear equations introduced in the previous tutorials can be used. Animated heat transfer modeling for the average Joe – part #3 by George Lungu – This is a new section of the beginner series of tutorials in heat… Read More... "Animated Heat Transfer Modeling for the Average Joe – part #3"

## Animated Heat Transfer Modeling for the Average Joe – part #2

This is a continuation of the first part of the beginner series of tutorials in heat transfer modeling. The first part introduced the reader to the concept of heat capacity (being analogous to the electrical capacity). This section continues with the concept of heat conductance which is analogous to the electrical conductance. Ohm’s law applies. Toward the end, the principle… Read More... "Animated Heat Transfer Modeling for the Average Joe – part #2"

## Animated Heat Transfer Modeling for the Average Joe – part #1

This the first tutorial on modeling heat transfer at a very introductory level. If you follow this series and spend your own effort in developing your own models you will be able to model heat transfer in very complex shapes (1D, 2D, 3D) in a short time and with the basic understanding of a 12 year old school boy. Animated heat transfer modeling… Read More... "Animated Heat Transfer Modeling for the Average Joe – part #1"

## A One-Dimensional Dynamic Heat Transfer Model – a diffusion model

Hi guys, Here is a 1D dynamic model I built today simulating heat transfer in a 21-segment bar. Just click on the orange “Demo” button for a quick demo. Hitting “Reset” sets the 21 segments of the bar to the initial conditions which is a fully customizable initial temperature map. Clicking “Start/Pause” starts the simulation and you can watch the bar temperature profile… Read More... "A One-Dimensional Dynamic Heat Transfer Model – a diffusion model"

## How to Model a Frequency Modulated (FM) Signal – an insight

Both frequency and phase modulation are important not only in electronics but also in science and physics in general. It seems like a trivial chore but when I first tried to model such a signal some time back I hit a hard wall. Our minds easily understand kinematics concepts such as coordinate, speed, acceleration and the relations between them in… Read More... "How to Model a Frequency Modulated (FM) Signal – an insight"

## Casual Introduction to Numerical Methods – spring-mass-damper system model – part#5

In this tutorial, most of the calculations for the numerical simulation a SMD (spring-mas-damper) system will be consolidated into a single formula, the coordinate formula. In this case, in order to calculate the coordinate at the end of a any time step, we will need just the coordinates from the previous two time steps and of course the input parameters (constants). These… Read More... "Casual Introduction to Numerical Methods – spring-mass-damper system model – part#5"

## Casual Introduction to Numerical Methods – spring-mass-damper system model – part#4

This tutorial explains the principles to generating animation for the spring-mass-damper system analyzed in the previous presentations. [sociallocker][/sociallocker] A casual approach to numerical modeling – part #4 – a Spring-Mass-Damper-System – creating the animation by George Lungu – We are trying to generate animation for the system sketched above knowing the deviation from the equilibrium function of time. This deviation is… Read More... "Casual Introduction to Numerical Methods – spring-mass-damper system model – part#4"

## 2D Projectile Motion Tutorial #7

In the this tutorial, after we got most of the trajectory calculation concentrated in just two columns, we will write a custom VBA function (dual output) to replace the spreadsheet computations used. This process of starting with very simple models, then refining the calculations and then learning how to write custom functions for those calculations will be extremely useful later for developing more complex models. [sociallocker][/sociallocker]… Read More... "2D Projectile Motion Tutorial #7"