Buckingham pi Definition and 17 Threads

  1. R

    Dimensional Analysis Buckingham Pi Theorem

    This is the problem I'm currently working on: The pi groups I identified were h1, h2, d, D, g, t, and velocity, but when I looked at the solution, it selected Δh, D, t, ρ, d, ϒ, h1, with no explanation why those variables are needed. If I was solving with the Bernoulli equation, I wouldn't...
  2. F

    Is Exponential Needed for Non-Repeating Variable in Buckingham Pi Theorem?

    Homework Statement https://projects.exeter.ac.uk/fluidflow/Courses/FluidDynamics3211-2/DimensionalAnalysis/dimensionalLecturese4.htmlaccording to this link , when we form the pi group , we need to put an exponent for the non-repeating variable ,( in this case , delta P is non-repeating variable...
  3. F

    Rules of choosing repeating variable in Buckingham pi theorem

    Homework Statement i was told by my lecturer that when we choose the repeating variables in pi buckingham theorem , we can choose based on 3 property , which is geometry property which consists of (length , width and area) , then followed by flow property ( velocity , acceleartion, discharge)...
  4. H

    Why do we need to raise the whole pi_3 to power of -1/2?

    Homework Statement in the third photo attached , why do we need to raise the whole pi _3 to power of -1/2 ? can we do so ? if we do so , the original pi_3 will be changed , right ? Homework EquationsThe Attempt at a Solution
  5. H

    Can Someone Explain Step 4 in the Buckingham Pi Theorem Homework?

    Homework Statement http://www-mdp.eng.cam.ac.uk/web/library/enginfo/aerothermal_dvd_only/aero/fprops/dimension/node9.html can somoene expalin about step 4 in the first photo attached ? What does it mean by each group has all the repeating variables and non-repeating variable ? Homework...
  6. B

    Buckingham Pi / Dimensional analysis

    Homework Statement A capillary filled with water is placed in a container filled with a chemical of concentration C_{0} , measured in number of molecules per unit volume. The chemical diffuses into the capillary of water according to the following relation (where x is distance along...
  7. V

    Help with Buckingham Pi theory on turbine

    I was wondering if someone is very well into the Buckingham Pi Theory and can assist me in understanding the outcome. I have two dimensionless equations and I need to get an understanding on how they were made by the Buckingham Pi theory. The situation is considered for the reynolds number...
  8. 5

    Buckingham Pi Theorem: Choosing Common Variables

    Homework Statement In buckingham pi theorem, you have p=n-k dimensionless groups (π1, π2,...) where n=number of total variables and k=number of total units among the variables For example, let's say we want to relate: ρ~m/L3 (density) μ~m/L*t (viscosity) v~L/t (velocity) d~L (distance) Da~L2/t...
  9. S

    Buckingham-Pi for "algorithmic" non-dimensionalization

    I would like to use the Buckingham-Pi theorem in order to "algorithmify" non-dimensionalization of existing equations. I can get things to work for very simple problems, but am running into issues with a harder example. I posted my question on physics.stackexchange.com the day before yesterday...
  10. C

    How to Determine Pi Groups for Fluid Flow Through an Orifice

    Homework Statement a) A orifice, diameter d (m), in the walls of a tank discharges water under a head, h (m), subjected to gravitational acceleration, g (m/s2). If the fluid has density, ρ (kg/m3)and viscosity, μ (Ns/m2), show that the quantity of fluid Q (m3/s) flowing out of the tank may...
  11. P

    Dimension Analysis and buckingham pi

    Homework Statement can someone explain why we are interested in forming dimensionless products and why only n-j of them should be formed from the problem's variables? Homework Equations Step 1: List the variables in the problem Step 2: Express each of the variables in terms of basic...
  12. G

    Dimensional Analysis and buckingham pi

    Homework Statement Hi Guys, I am a bit confused concerning one part of this topic. Specifically when trying to find non dimensional groups. My problem is a small thing in the finding of the indices. So, for example, your are trying to find a pi group when finding the drag on a car. so you...
  13. SSGD

    Variable Set Distribution - Buckingham Pi Theorum

    Background: I am trying to write a program for Buckingham Pi Groups. I need to find a way to list all the input varialbes as different sets. For example if I have 4 variables [V D p u] and I want to distribute them 3 ways I get 4 sets. Number of Sets = Binomial(Number of Variables...
  14. J

    Buckingham Pi Theory: Propeller & Pipe Flow Analysis for Jay

    Hi I feel I am competent enough at the Buckingham Pi theory regarding both Pipe flow and for Propeller analysis. Derive a relationship between the volume flow rate and rotational speed of propeller in terms of the diameter of the pipe and propeller and also fluid characteristics density and...
  15. G

    Buckingham PI Theorem proof - Dimensional Analysis

    Homework Statement I am looking for a proof of Buckingham PI theorem in dimensional analysis, but can't really find one anywhere. I saw a proof involving posing the problem as a question in linear algebra, but it was quite unclear.
  16. G

    Dimensional Analysis & Buckingham Pi Theory

    What can "Dimensional Analysis Techniques & Buckingham Pi Theory" be used for? GS
  17. C

    How Does the Buckingham Pi Theorem Apply to Homogeneous Functions in Physics?

    This is more of a dimensional analysis or unit analysis problem than a basic analysis problem. So if I didn't post this thread in the right forum, please delete it. Moving on, I'm having trouble grasping the concepts behind the Buckingham Pi Theorem. After reading some textbooks and doing...