Recent content by Nick Bruno

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    Undergrad 4th order homogeneous linear ODE with constant coefficients

    looks like you may need to use sturm-liouville and use a computer to solve your problem.
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    Graduate Understanding Duhamel's Principle: A Grad Math Survival Guide

    no advice eh?
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    Undergrad 4th order homogeneous linear ODE with constant coefficients

    this may help you. Its something i made for the 1d 4th order wave eqn... i think you will find pg 7 handy.
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    Graduate Understanding Duhamel's Principle: A Grad Math Survival Guide

    Hi, I am having difficulty understanding and applying Duhamel's principle. (I'm not great with math but somehow I found myself in this graduate math class of death)... From my text its stated that Ux1x1+Ux2x2+...+Uxnxn - Utt = f(x,t) (for x an element of all real), t>0 u(x,0)=0...
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    Finding integral of a helicoid

    you don't HAVE to use phi(theta,phi), you can do this in cartesian coordinates... but i think it would be easier to use a different coordinate system. ( i would suggest trying spherical?) Yes, I you have to change the object of the integral if you want to use a different coordinate system...
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    Finite Sum Convergence: Solving for n in the Equation n^2 + 3n - 2 = 0

    1. Homework Statement [/b] See attached 2. Homework Equations See attached 3. The Attempt at a Solution I know the answer is 6 or zero... but I can't figure out how to "show" this. When typing this equation into my calculator, I can clearly see that the number always ends in .0...
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    Solving Infinite Coupled ODEs to Tackling Complex Systems

    well, you have multiple unknowns and 2 equations. u need as many equations as you have unknowns. Maybe you can choose i such that you have enough equations to solve?
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    Calc 3 partial derivative review for PDE's class

    Thanks, this worked and was actually quite a clever way to solve the problem.
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    Calc 3 partial derivative review for PDE's class

    do you mind refreshing me on implicit differentiation?
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    Calc 3 partial derivative review for PDE's class

    [b]1. Homework Statement I am suppose to use polar coordinate data to find derivatives, ie x = r cos(theta) y = r sin(theta) r^2 = x^2 + y^2 [b]2. Homework Equations show dtheta/dy = cos(theta)/r show dtheta/dx = -sin(theta)/r...
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    Understanding Stagnation Pressure in Cooling Fans

    I have seen a cooling problem solved in COMSOL which, I think is a form of CFD and the results were accurate and neat to look at too! I have a quesiton, why do you say "Turbulent flow against the part to be cooled is MUCH more effective than laminar flow." I don't understand these physics.
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    Understanding Stagnation Pressure in Cooling Fans

    this is an interesting site you may like. If you click tutorials on the side bar it takes you to a balancing tutorial and talks about different kinds of coolers etc...
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    Understanding Stagnation Pressure in Cooling Fans

    So basically you are just measuring the velocity of the flow?
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    Modeling Heat Transfer with Comsol

    smaller step sizes?
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    Rotating disk with friction on the boundary

    There may be something in Shigleys machine design book?