Search results
Results from the WOW.Com Content Network
The hydraulic diameter, D H, is a commonly used term when handling flow in non-circular tubes and channels. Using this term, one can calculate many things in the same way as for a round tube. When the cross-section is uniform along the tube or channel length, it is defined as [1] [2] =, where
M - The mass of the accelerated shell or sheet of material (usually metal). The shell or sheet is often referred to as the flyer, or flyer plate. V or V m - Velocity of accelerated flyer after explosive detonation N - The mass of a tamper shell or sheet on the other side of the explosive charge, if present
In geometry, a spherical shell is a generalization of an annulus to three dimensions. It is the region of a ball between two concentric spheres of differing radii. [1]
This formula is valid only for configurations that satisfy < < and () <. If sphere 2 is very large such that r 2 ≫ r 1 {\displaystyle r_{2}\gg r_{1}} , hence d ≫ h {\displaystyle d\gg h} and r 2 ≈ d {\displaystyle r_{2}\approx d} , which is the case for a spherical cap with a base that has a negligible curvature, the above equation is ...
D o is the inside diameter of the outer pipe, D i is the outside diameter of the inner pipe. For calculation involving flow in non-circular ducts, the hydraulic diameter can be substituted for the diameter of a circular duct, with reasonable accuracy, if the aspect ratio AR of the duct cross-section remains in the range 1 / 4 < AR < 4. [11]
For the thin-walled assumption to be valid, the vessel must have a wall thickness of no more than about one-tenth (often cited as Diameter / t > 20) of its radius. [4] This allows for treating the wall as a surface, and subsequently using the Young–Laplace equation for estimating the hoop stress created by an internal pressure on a thin-walled cylindrical pressure vessel:
Defined by Wadell in 1935, [1] the sphericity, , of an object is the ratio of the surface area of a sphere with the same volume to the object's surface area: = where is volume of the object and is the surface area.
Thin cylindrical shell with open ends, of radius r and mass m. This expression assumes that the shell thickness is negligible. It is a special case of the thick-walled cylindrical tube for r 1 = r 2. Also, a point mass m at the end of a rod of length r has this same moment of inertia and the value r is called the radius of gyration.