Ch 6. Modeling and Similitude fl Multimedia Engineering Fluids DimensionalAnalysis Similitude DimensionlessGroups
 Chapter 1. Basics 2. Fluid Statics 3. Kinematics 4. Laws (Integral) 5. Laws (Diff.) 6. Modeling/Similitude 7. Inviscid 8. Viscous 9. External Flow 10. Open-Channel Appendix Basic Math Units Basic Equations Water/Air Tables Sections Search eBooks Dynamics Statics Mechanics Fluids Thermodynamics Math Author(s): Chean Chin Ngo Kurt Gramoll ©Kurt Gramoll

 FLUID MECHANICS - CASE STUDY Introduction An Attack Submarine in the Deep Sea Click to view movie (244k) A 1:10 scale model of an attack submarine is being tested in a water tunnel. The drag force ratio the submarine in the deep sea and the submarine model in the tunnel need to be estimated. The submarine cruises at 4 m/s in seawater (viscosity, μ = 1.2×10-3 N-s/m2 and density, ρ = 1,030 kg/m3). The fresh water in the tunnel is maintained at a temperature of 40 oC. Questions What should the velocity of the model be in the tunnel? Determine the drag force ratio of the submarine prototype and model. Approach Assume the submarine is far from the water surface. Assume the compressibility of water is negligible.