Recent content by smegal

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    Fluid mechanics Reynolds number equation query

    kg/m^3 That is a very low density.
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    Fluid mechanics Reynolds number equation query

    1.I have been asked to: Calculate the density of a fluid if a ctitical velocity of 2m/s at Re=2000 in a pipe of bore 90mm at a dynamic viscosity oc 0.09cP I have calcualted the variables to SI units and found \rho=? Um (V) =2m/s D=0.09m \mu=0.09X10^-3 I am rearranging this...
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    How to Calculate Stress on Thin-Walled Cylinder Subjected to External Pressure?

    Yeah I see where you are coming from. Is there any method for accounting for this? at my chosen depth and dimensions (10m length 5m diameter) the volume of the submarine changes by -0.31551m^3 this shows a fair bit of buckling. That is the reason I was mentioning the hoop stress as it is...
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    How to Calculate Stress on Thin-Walled Cylinder Subjected to External Pressure?

    Thank you! That's that part sorted. If I was trying to run the calculations backwards to find the safe dive depth (using a safety factor of 1.75) do I need to perform any calculations with regard to the yield strength of the material or do I simply use the circumferential strain acting upon...
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    How to Calculate Stress on Thin-Walled Cylinder Subjected to External Pressure?

    Would you say that modelling a submarine as a sphere and a cylinder is an accurate method? Or is there another way that I have overlooked. Ps thanks for your reassurance. This work was beginning to stress me out a little.
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    How to Calculate Stress on Thin-Walled Cylinder Subjected to External Pressure?

    I am not 100% sure if I have done it right but I believe that for the hemispheres the strain is calculated using Sphere_strain=(1/E)*(sphere_stress-Pr*sphere_stress) I read in a textbook (Theory and design of modern pressure vessels John F Harvey) that the stresses acting upon a spherical...
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    How to Calculate Stress on Thin-Walled Cylinder Subjected to External Pressure?

    1. I am trying to analyse the hydrostatic pressures exerted on a submarine at depth Firstly If I model the submarine as being two hemispherical ends with a cylindrical section. Am I correct to model them seperately then combine the results at the end to calculate the deformation or is there a...
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