The impact of a bilateral symmetric discharge structure on the performance of a scroll expander for ORC power generation system

CFD modelling of small scale ORC scroll expanders using variable wall thicknesses

“…The dynamic mesh technology provided by ANSYS FLUENT [32] was employed to generate the eccentric movement of the orbiting scroll relative to the fixed scroll while changing the enclosed working chamber volumes over time. The dynamic mesh is the most common approach to capture the fluid motion in the complex scroll expander geometry and to reproduce the eccentric movement of the orbiting scroll by means of user-defined functions [12,24,[26][27][28]33,34]. The smoothing and remeshing dynamic mesh schemes were combined and enabled in order to regenerate and recalculate the deforming and moving mesh in the expander working chambers at each time step.…”

“…CFD simulations of scroll machines have been increasingly conducted in recent years for investigation of the inner working process [12,[23][24][25][26][27][28]. The understanding developed has contributed to performance predictions which are useful for preliminary design and the further improvement of the scroll geometry itself.…”

“…This would enable the capture of spatial inner flow characteristics, evaluation of accurate time-averaged flow and temperature fields and consideration of the effects of lubricating oil. Drawing upon these findings, Song et al ( ,2018 [26][27][28] established a 3D CFD model to analyse the inner working process of a scroll expander with a particular focus on the unsteady suction process and the effects of suction port arrangements. They also developed a CFD model for a small-scale ORC scroll expander with a bilateral discharge structure (two discharge ports) to investigate its influence on the expander aerodynamic performance.…”

Feasibility Assessment of a Dual Intake-Port Scroll Expander Operating in an ORC-Based Power Unit

“…In [23], a symmetric discharge structure was proposed for scroll machines. The results show that the new configuration allows for the reduction of the discharge pressure, leading to a more uniform flow distribution in the backpressure and discharge chambers, thus enhancing the driving moment and positively affecting the machine's performance.…”

CFD analysis of the influence of variable wall thickness on the aerodynamic performance of small scale ORC scroll expanders

“…Two-(2D) and three-dimensional (3D) computational grid approaches to discretise the scroll domain along with the application of different moving mesh methods, to update the deforming mesh over time, can be found in the literature [8][9][10][11][12][13][14][15]. According to Morini et al (2015) [6], a 2D CFD approach is sufficient to evaluate pressure fluctuations in the suction and discharge region in addition to mass flow rate profiles.…”