Recent content by spearo

I found a study on sonar arrays being dragged through the ocean, I will post it when I find it again. The diameter was only 1mm however and the length was 100m in a 900m test tank. Before I read this comprehensive report would this be appropriate? If it cannot be estimated and I make a test...

So which one should I use? I posted them all to illustrate why this is confusing. I want to be able to compare the drag on the 2 different spears at the stated velocities to determine which is has more kinetic energy and momentum at a given range. I understand that it will only be an...

Bonehead, Is it a range than similar to the transonic region for airfoils?

Thankyou for your insights. To be honest I am not sure if they are the appropriate equations as the source only made reference to laminar and turbulent flow. Based on what you said then I take it there will be turbulent flow, not laminar? Sorry for all the questions I have not studied maths or...

Could you please explain a little further, surely the length has some significance as it determines the "skin". which of these is appropriate to this shape as they do not all have reference to Re. I am finding so much mixed information. 1/7 power law: 1/7 power law with experimental...

This is not a coursework question to be clear, it is the science behind a homemade speargun DIY project. The velocities were estimated based on the mass of the components and the force of the rubbers.

I realize that that kinematic viscosity is for water not seawater but that is not the problem as I still got ~88 mllion...

Hi, I am having trouble calculating the reynolds number for 2 spear shafts underwater. The two shafts vary in diameter and velocity. The tips are identical, stream lined to a fine point so the flow should be laminar. Both spears are 1.9304 m long. The diameters are 11/32" (8.73125mm) and 3/8"...