This is an online version of the downloadable calculator; Pressure Vessels.

The same technical help page applies.

The above calculator identifies the *internal* volume(s) of a vertical pressure vessel with spherical end caps.

The vessel comprises five distinct sections; a lower head (V₁,d₁), a lower knuckle (V₂,d₂), a central cylinder (V₃,d₃), an upper knuckle (V₄,d₄) and an upper head (V₅,d₅).

The upper and lower heads are identical, as are the upper and lower knuckles.

The output (calculation results) are displayed in two columns; the vessel to the left and the fluid (fill) to the right. If a particular section (e.g. V₂,d₂) is full, both columns will display the same result.

Due to the Idiosyncrasies of javascript mathematics, you may sometimes receive a 'NAN' result in the fluid column for one or more of the results for a full vessel. When this occurs, you will need to reduce the fill-height (h) slightly; e.g. for a vessel height of '5' (H=5), you may have to set the fill height (h) to 'h=4.9999'

For a **spherical vessel**, simply set the knuckle radius to zero (r=0), give the heads the same radius as the cylinder (R = ½.Ø) and enter a height twice the same radius (H = Ø).

For plain (flat) heads simply enter a very large head radius, for example; R = 1000.

If you have entered an illegal value, e.g. h>H you will activate an alert.

Øₕ Fluid (bottom of the RH column): shows the surface diameter of the fluid in the head. If the fluid height (h) is lower than d₁, this value will show the fluid surface diameter in the lower head. If the fluid height (h) is between d₄ & d₅, this value will show the fluid surface diameter in the upper head.

The above calculator identifies the *internal* volume(s) of an horizontal pressure vessel with spherical end caps.

The vessel comprises five distinct sections; a left-hand head (V₁,d₁), a left-hand knuckle (V₂,d₂), a central cylinder (V₃,d₃), a right-hand knuckle (V₂,d₂) and a right-hand head (V₁,d₁).

The left-hand and right-hand heads are identical, as are the left-hand and right-hand knuckles.

The output (calculation results) are displayed in two columns; the vessel to the left and the fluid (fill) to the right. The output results for fill volumes (V₁ to V₃) and dimensions (d₁ to d₃) in this calculator are a little different to the vertical vessel option.

In the left-hand [results] column:

d₁ is the depth of, and V₁ is the capacity volume of, a single spherical head, therefore these results apply to each end.

d₂ is the depth of, and V₂ is the capacity volume of, a single knuckle, therefore these results apply to each end.

d₃ is the depth of, and V₃ is the capacity volume of, the central cylinder.

The total volume is therefore; 2.(V₁+V₂)+V₃

In the right-hand [results] column:

d₁ is the depth of fluid to the bottom of the spherical heads. V₁ is the volume of fluid inside a single spherical head. Therefore these results apply to each end.

d₂ is the depth of fluid to the bottom of the knuckles. V₂ is the volume of fluid inside a single knuckle. Therefore these results apply to each end.

d₃ is the depth of, and V₃ is the capacity volume of, the central cylinder.

The total volume is therefore; 2.(V₁+V₂)+V₃

Due to the Idiosyncrasies of javascript mathematics, you may sometimes receive a 'NAN' result in the fluid column for one or more of the results for a full vessel. When this occurs, you will need to reduce the fill-height (h) slightly; e.g. for a vessel height of '5' (H=5), you may have to set the fill height (h) to 'h=4.9999'

For a **spherical vessel**, simply set the knuckle radius to zero (r=0), give the heads the same radius as the cylinder (R = ½.Ø) and enter a height twice the same radius (H = Ø).

For plain (flat) heads simply enter a very large head radius, for example; R = 1000.

If you have entered an illegal value, e.g. h>H you will activate an alert.

The "**Reset**" button clears all calculations on the page and reinstalls default values (this button may not respond in the FireFox browser).

Reset can also be achieved by pressing the "F5" key.

The **Calculate** button calculates the associated option only.

Hover your cursor over the symbols for an associated description.

Full downloadable version of this calculator is available from this website at; Pressure Vessels.

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