| 1. |
- Aad, G., et al.
(författare)
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- 2012
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swepub:Mat__t (refereegranskat)
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| 2. |
- Gao, Zhi xin, et al.
(författare)
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Progress of passive enhanced heat transfer tubes
- 2017
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Ingår i: Xiandai Huagong/Modern Chemical Industry. - 0253-4320. ; 37:3, s. 24-30
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Forskningsöversikt (refereegranskat)abstract
- A review of several typical enhanced heat transfer tubes such as corrugated tube, transversally corrugated tube, twisted tube and spiral fluted tube, is carried out. Compared with smooth wall tube, these enhanced tubes have higher heat exchange capacity and better anti - fouling ability. Besides, the heat transfer efficiency can be promoted to a higher level if the objects that can disturb flow are put in the tubes. However, higher heat transfer efficiency of such enhanced heat transfer tubes can only be achieved under certain conditions. Therefore, new heat transfer tubes that could avoid the formation of mobile dead-zone should be designed to meet the broad applications or facilitate better heat transfer effect.
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| 3. |
- Jin, Zhi Jiang, et al.
(författare)
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Computational fluid dynamics analysis on orifice structure inside valve core of pilot-control angle globe valve
- 2018
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Ingår i: Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science. - : SAGE Publications. - 0954-4062 .- 2041-2983. ; 232:13, s. 2419-2429
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Tidskriftsartikel (refereegranskat)abstract
- A novel pilot-control angle globe valve is proposed, and it has an obvious advantage of energy conservation during its opening and closing process. In pilot-control angle globe valve, the opening and closing forces are related to the orifice located inside the valve core. In this paper, the effects of orifice diameter are thoroughly studied under different working conditions such as valve core displacements and inlet velocities. To begin with, the numerical model is validated by comparing similar angle valves, and then the flow and loss coefficients under different orifice diameters are discussed. It is found that the effects of orifice diameter on force acting on valve core depend on valve core displacement and inlet velocity. Thus different valve core displacements and inlet velocities combined with different orifice diameters are further studied. It is also found that when the orifice diameter is larger than 12 mm, pilot-control angle globe valve cannot be used under small inlet velocity or large valve core displacement. In addition, formulas to calculate forces on valve core are proposed for further orifice design. This work can be referred in process industries especially in a piping system with orifice plates or globe valves.
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| 4. |
- Qian, Jin-Yuan, et al.
(författare)
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Effects of orifice on pressure difference in pilot-control globe valve by experimental and numerical methods
- 2016
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Ingår i: International Journal of Hydrogen Energy. - : Elsevier BV. - 1879-3487 .- 0360-3199. ; 41:41, s. 18562-18570
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Tidskriftsartikel (refereegranskat)abstract
- Pilot-Control Globe Valve (PCGV) can utilize pressure difference caused by fluid flow through the orifice on valve core as its power, for open and close the main valve with a small pilot valve. It has obvious advantages of energy conservation and quick response. Orifice structure on the valve core is the main component to determine the pressure difference, which is used to push the valve core. In this paper, the numerical model with User Defined Functions (UDFs) method is carried out, and the experimental device is arranged. The numerical and experimental results of valve core displacements achieve agreements. Then, analysis of pressure difference under different static pressures, inlet velocities and different orifice diameters are carried out. It shows that pressure difference has no relationship with static pressure, thus PCGV can be adopted in hydrogen pipelines. Meanwhile, higher inlet velocity can turn out larger pressure difference with quicker response of PCGV. In addition, there exits an unbalanced moment, and 15 mm is the extreme diameter of the orifice for DN150 PCGV. Finally, the design method of the orifice structure in PCGV is proposed with design formulas. This work can help the precise design work of PCGV, and it can be referred by other researchers who are also deal with orifice structures in similar valves design work.
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