كليدواژه :
انتشار , پالايشگاه پتروشيمي , Autodyn , موج انفجار , TNT
چكيده فارسي :
در حوادث اوليه مانند انفجار در يك محيط پتروشيمي، بسته به فاصلهي در نظر گرفته شده بين مخازن، انفجار مي تواند مانند اثر دومينو به ديگر مخازن انتقال يابد. در اين مطالعه با توجه به ابعاد بزرگ محوطه مخازن پتروشيمي، ابتدا مخازن درجانمايي و فواصل مختلف از هم در مقياس در نرمافزار Autodyn مدل سازي و به بررسي انتشار امواج انفجار و محصور شدگي فشار 8 گرم TNT در محيط بين مخازن پرداخته شده است. در ادامه به بررسي تاثير شكل ديوارهاي ضد انفجار مختلف در كاهش فشار انفجار و نحوه برخورد موج ناشي از 1000 كيلوگرم TNT در فاصله سرد 20 متر به يك مخزن پتروشيمي در مقياس واقعي پرداخته شده است. نتايج نشان مي دهد كه استفاده از روابط نيمه تجربي آيين نامه UFC-0-340-02 در محيط هاي بسته به دليل تشديد اضافه فشار انفجار غيرمحافظه كارانه است. همچنين بهترين شيوه جانمايي مخازن در اين بررسي، آرايش زيگزاكي با در نظر گرفتن فاصلهاي 2 برابر فاصله ايمن بين مخازن از آيين نامه NFPA-30 است. علاوه بر اين، نتايج نشان مي دهد با ايجاد مانع در برابر انفجار مي توان تا حد زيادي انفجار را كاهش داد اما شكل مانع تاثير چنداني را ايجاد نمي كند.
چكيده لاتين :
The most important danger that threatens a petrochemical refinery is an explosion, which is followed by a fire
or vice versa. In fact, the occurrence of initial events such as explosions and fires spread from one part to
another like the domino effect if the distance between the storage tanks is not sufficiently considered.
Therefore, the distance and arrangement of petrochemical storage tank can play an important role in reducing
the damage of initial accidents. So far, due to the explosion uncertainties, no definitive solution has been
offered, but a combination of active and passive techniques such as the efficient use of intelligence and security
organizations, increasing the scaled distance between the detonation point and the target buildings or providing
physical barriers, the use of deformable materials to absorb energy, and the use of appropriate retrofit structural
techniques can reduce the effects of explosions. As it turns out, it is virtually impossible to study the
propagation of blast waves experimentally on a large scale due to financial constraints and potential hazards.
Therefore, to solve this problem, two solutions are proposed: the use of small-scale laboratory methods and
the use of numerical methods. Three-dimensional numerical analysis is an efficient method for investigating
structural weaknesses, hazard risk analysis, and evaluating of explosion hazard points. In this study, with the
help of explosion simulation by Eulerian-Lagrangian coupling method, the research has been surveyed in two
parts. In the first part, petrochemical tanks in different arrangements, and,at different distances from each
other are modeled in 3D on Autodyn software on the scale of
1
200 and the propagation of explosion waves
and the confinement of 8g of TNT pressure in the environment between the tanks are investigated. In the
second part, the effect of barrier shape on reducing the blast pressure of 1000 kg of TNT on a real scale has
been investigated. The results show that the use of semi-empirical relation in UFC-0-340-02 to determine the
blast pressure is applicable only to open environments, and it is not precise in closed environments due to the
confinement of the blast pressure. Moreover, the results show that it is not conservative to use the required
distance between tanks considering the amounts proposed by the regulations. As a result, increasing the
distance up to twice the amount proposed by the regulations, the effect of explosion pressure confinement is
eliminated. The best way to position the tanks in this study is a zigzag pattern with a distance equal to twice
the safe distance between the tanks in accordance with NFPA-30. In addition, the results show that by creatinga barrier against the explosion, the explosion over-pressure can be greatly reduced, but the shape of the barrier
does not have much effect. Although, using the Eulerian-Lagrangian coupling method requires considerable
time and appropriate software to perform the calculations, it provides a comprehensive understanding of the
blast wave interaction with structures. With the advancement of technology and the use of parallel processing
in the cloud space, and the mapping technology it is possible to evaluate the different structures on a real scale
against the explosion
