What is the “gurgling effect” of storage tanks?
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While reviewing the general contract today, regarding the requirements for storage tanks, I came across this line: In accordance with Appendix E of the API650 standards, the height of the containers must be controlled to prevent the occurrence of gurgling effects. I checked API650 and didn’t find any specification regarding height; it seems to be a version issue. Question: What is the so-called “gurgling effect”? Or, what are the negative consequences if the height of the oil tank is too high?
I hope experts can answer this question; it’s the first time I’ve heard of this term – it’s a new expression!
I can’t find this term on Baidu at all; I’ve never seen any articles like it. Please let those who are aware inform me
Haven’t heard of it; I hope someone with more knowledge can give some advice.
This post was last edited by flute6 on 2010-1-12 at 13:54. Appendix E of the API650 standard deals with the seismic design of storage tanks. The horizontal loads are divided into two parts: the first part consists of the impact loads generated during an earthquake on the tank shell, the tank top, and those parts of the liquid stored within that move together with them; the second part refers to the shaking loads caused by resonance between the long-period components of seismic waves and the liquid stored in the tank during an earthquake. However, only the first mode of vibration is taken into consideration. D: diameter of the tank; H: height of the tank. W1: effective weight of the liquid in the part that moves together with the tank shell. W2: effective weight of the liquid during oscillations in a single mode. From the relationship curve between W1, W2, D, and H, it can be seen that the larger the D/H ratio, meaning the tank is taller and thicker, the smaller W1 becomes while W2 increases. Due to limitations imposed by the soil’s bearing capacity, there is a certain limit to the height of oil tanks. For large oil tanks, increasing the volume requires an increase in diameter; hence, large oil tanks have a higher D/H ratio. The larger the volume of the oil tank, the smaller the portion of the liquid that moves in unison with the tank walls; as a result, the proportion of W1 becomes smaller, while the proportion of the liquid that oscillates (i.e., W2) becomes larger. Generally, with a constant volume, increasing D and decreasing H can reduce the overturning moment M.
First of all, I thank flute6 for their answer, and I’m also very grateful for the attention from the fellow netizens above. When I left work yesterday, I took the opportunity to ask a colleague who has been working in static equipment installation for many years for some advice. His explanation is that if the height of the large tank is too great, then when the liquid level inside the tank is high, the bubbles at the bottom of the tank increase in volume as they rise to the top of the tank, and they burst there, thereby causing stress on the tank. At first glance, his explanation seems quite reasonable, but upon closer analysis, there are still problems with it. Here, it’s like offering a starting point to encourage others; let’s see if more experts can provide additional ideas or explanations. Thank you again to the fellow travelers upstairs!
I think it’s when the liquid level in the tank is too high; the vibration of the liquid inside the tank exerts force on the tank, causing it to shake.
It’s really the first time I’ve heard this term; I hope someone experienced can teach me.*