Rotor profile design and numerical analysis of 2–3 type multiphase twin-screw pumps

Abstract

. Rotor profile design and numerical analysis of 2-3 type multiphase twin-screw pumps. Proceedings of the Institution of Mechanical Engineers, Part E: Journal of Process Mechanical Engineering, doi: 10.1177/0954408917691798 This is the accepted version of the paper.This version of the publication may differ from the final published version. Abstract: Increasing demands for high-performance handling of fluids in oil and gas as well as other applications require improvements of efficiency and reliability of screw pumps. Rotor profile plays the key role in the performance of such machines. This paper analyses difference in performance of 2-3 lobe combination of a twin screw pumps with different rotor profiles. Atype profile formed of involute-cycloid curves and D-type formed of cycloid curves are typical representatives for 2-3 type screw pumps. The investigation is performed by use of a full 3-D Computational Fluid Dynamics (CFD) analysis based on a single-domain structured moving mesh obtained by novel grid generation procedure. The real-time mass flow rate, rotor torque, pressure distribution, velocity field were obtained from 3D CFD calculations. The performance curves under variable rotation speed and variable discharge pressure were produced. The CFD model was validated by comparing the simulation results of the A-type pump with the experimental data. In order to get the performance characteristics of D-type profile, two rotors with D-type profile were designed. The first has the same displacement volume as A-type and the second has the same lead and rotor length as A-type but different displacement volume. The comparison of results obtained with two rotor profiles gave an insight in the advantages and disadvantages of each of two rotor profiles analysed. Permanent

A Novel Engagement‐Pixel Tracking Method for Meshing Clearance Layout of Twin‐Screw Rotors

“…According to equation (5), when the helix parameter θ, evaluated from 0 ∘ to 360 ∘ , of each end-section pro le is known, the corresponding contact line point coordinates r c (x c , y c , z c ) can be obtained by substituting the rotational angle φ 1 into equation (5) yielding the corresponding value u.…”

“…erefore, the tooth root clearance of the female rotor can be determined only on the basis of the requirement of the tooth root clearance. (5) Arrange the Clearance between the Long-edge Segments of the Male and Female Rotors. Since the longedge segments of the two rotors engage through point contact, it only needs to adjust the pitch point and the tooth root coordinates on the male and female rotors.…”

“…At present, in order to improve the performance of rotary compressors, one of the major research trends is to optimize the theoretical and actual rotor profiles [5][6][7][8]. For the purpose of optimization, working clearances need to be arranged.…”

Experimental and Numerical Analysis on Flow Characteristics in a Double Helix Screw Pump

“…It has been considered that an asymptotic value is reached for a mesh number of 3,862,159. what has been chosen by Yan. et al [12,13,16], using a polyhedral mesh set-up. However, the present grid number is probably not sufficient inside the flank gaps (see the enlarged region on the left side of Figure 4a) in between the two screws.…”

“…Wang Chun-lin [10] and Tang Qian [11] simulated the three-dimensional turbulent flow field inside the trapezoidal labyrinth screw pump, for the first time, with clear water conditions and obtained the main performance characteristics and some local internal flow characteristics. More recently Yan et al performed numerical studies using the moving mash technique [12], and applied it to the cavitation problem in the screw pump type [13].…”