Abstract:

Liquefied natural gas (LNG) submerged pump is designed to immerse its canned motor and pump body into cryogenic liquid. To reduce radial and axial sizes, special guide vanes with different structures from popular ones are used. By analyzing the LNG pump structure, two key geometric parameters, inlet width and turning angle, were investigated to see how they affect pump hydraulic performance in the design. LNG pump guide vanes with different inlet widths and turning angles were designed to assemble the same impeller. Three-dimensional turbulent flows of different models were then numerically simulated using a standard k-ε turbulence model with ANSYS CFX. The comparative study revealed that optimum value of inlet width exited, and was larger than experience-based values. Inlet width had great influence on the pump performance, while turning angle was much less important. Therefore, designing an LNG pump guide vane, inlet width should be given high priority, and turning angle should be adjustable for structural design.

Key words: guide vane, inlet width, numerical simulation, turning angle, liquefied natural gas (LNG) submerged pump