Modeling and intelligence calculation about depth and gauge of deflected storage tank

After a storage tank is used for along time, its body comes up longitudinal or lateral displacement that changes the volume scale. Several mathematical models are setup to depict the displacement. A little flat-end elliptical oil tank and big (real size) column-brad oil tank are discussed. The former has normal condition and longitudinal deflected condition. The later has also two situations, that is, normal one and longitudinal and lateral displacement. The model is very difficulty by integration, but it becomes easy if we use intelligence calculation (Monte-Carlo method) to calculate. The relations between altitude and volume of storage tank are given. The results show the calculation is precision when there are plenty of the number of random points in Monte-Carlo method, such as, more than 10000 points. The problem of scale of tank volume has been solved, but also the results certificate that the intelligent algorithm is easy and efficient method in approximate calculation.