The Numerical Computation Of Transient Heat Transfer Problems Of The Floating-roof Tank In Daqing N.Tank Farm

In recent years, in order to apply the changing selling market of the petroleum internationally, a lot of large and medium oil fields implement many projects for increasing strategic petroleum reserves. Along with the increment of the amount of the oil storage tanks, it brings about lots of difficulties to manage them. The temperature of the crude oil could not be under some numerical value, because of the required time. It must heat up the oil storage tanks so as to make them run safely. But, because the temperature distributions are not known in the oil tanks when their temperatures drop, there is some blindness to operate by experience. The paper carries through under this background.At first, this work analyses the datas and modeling of the temperature drop which bases on the 9 floating-roof tank in Daqing N. Tank Farm. It gains the distribution rule and the temperature drop rule of the oil in the floating-roof tank. The calculator of the drop rate realizes the visualization, by using C# language, which makes the calculation be easier and more convenient. Then, this paper studies and analyses the temperature field, the flow field and the heat transfer mechanism in the process of oil temperature drop in the steady tank (the height of the petroleum in the tank is immobile). This paper uses the CFD method concretely. In the view of concrete model storage tank, the writer makes use of computational fluid dynamic software FLUENT to put up numerical simulation of crude oil temperature drop and the discussion of heat transfer mechanism. It convinces that the temperature difference between inside and outside of the tank leads to density changing, gets the conclusion that natural convection plays the decisive role in the process of heat transmitted and obtains the distribution chart of the floating-roof tank's field of velocity and temperature. This paper also makes contrast analysis between the values obtained by the software computation and the actual testing valeus, which is based on locale test.In a word, this paper enriches the investigation method of the temperature drop in oil tank through this work. It also supplies reference to calculating temperature drop rate, computational model simulation to realizing economical efficiency in oil depot, theoretical reference to operating storage tank naturally.