Free engineering calculators and unit convertersceo@instrumentationblog.in
Level Measurement · Free Calculator

Horizontal Tank with Dished Ends Volume Calculator

Calculate the liquid volume in a horizontal cylindrical vessel with 2:1 elliptical, hemispherical or flat heads at any level.

2:1 elliptical headsHemispherical headsPartial volumeStrapping table
Liquid volume12.441 m³
In litres12,441.3 L
Percent of volume37.09 %
Total volume33.543 m³
Both heads, full4.091 m³
How this result was calculated
  1. Shell: L × [R² acos((R − h)/R) − (R − h)√(2Rh − h²)]
  2. Two heads together form an ellipsoid: (a/R) × πh²(3R − h)/3, a = head depth = 0.625 m
  3. Total = 12.441 m³

Level to volume strapping table

Level %LevelVolumeVolume %
0 %0 m0 m³0.0 %
10 %0.25 m1.6474 m³4.9 %
20 %0.5 m4.6188 m³13.8 %
30 %0.75 m8.3149 m³24.8 %
40 %1 m12.441 m³37.1 %
50 %1.25 m16.772 m³50.0 %
60 %1.5 m21.102 m³62.9 %
70 %1.75 m25.228 m³75.2 %
80 %2 m28.924 m³86.2 %
90 %2.25 m31.896 m³95.1 %
100 %2.5 m33.543 m³100.0 %
Advertisement

Dished Head Volume

V = L × [R² acos((R − h)/R) − (R − h)√(2Rh − h²)] + (a ÷ R) × π h² (3R − h) ÷ 3

a is the depth of one head: D/4 for 2:1 elliptical heads, D/2 for hemispherical. The two heads together are treated as one ellipsoid, which is exact for these head types.

Worked example

A 2.5 m × 6 m vessel with 2:1 elliptical heads holds 29.45 m³ of shell plus 4.09 m³ of heads = 33.54 m³ when full; at 1.0 m level it holds about 12.44 m³ (37.1 %).

Key insight: torispherical (ASME F&D) heads are very common but their volume needs a separate formula; treating them as 2:1 elliptical slightly overestimates the head volume.
Advertisement

Frequently Asked Questions

What is a 2:1 elliptical head?

A head whose depth is one quarter of the vessel diameter, giving a 2:1 ratio between its major and minor axes.

What is the volume of a 2:1 elliptical head?

π × D³ ÷ 24 for one head, which is half the volume of a hemispherical head of the same diameter.

Are torispherical heads covered?

Not exactly. Use the 2:1 elliptical option as an approximation, or the manufacturer’s strapping table.

You May Also Like

Learn more on the blog

Basics of level measurement

A practical, field focused guide on instrumentationblog.in that explains the theory behind this calculator and how engineers apply it on real plants.

Read Full Article

More Level Measurement Calculators

More Calculator Categories