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A Mathematical Model for Simulation of Flow Rate and Chamber Pressures in Spool Valves
Date
2019-02-01
Author
Afatsun, Ahmet C.
Balkan, Raif Tuna
Metadata
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In this paper, a mathematical model to simulate the pressure and flow rate characteristics of a spool valve is derived. To improve the simulation accuracy, the discharge coefficient through the spool valve ports is assumed to be a function of both the Reynolds number and the orifice geometry rather than treating it as a constant. Parameters of the model are determined using the data obtained by computational fluid dynamics (CFD) analyses conducted on two-dimensional axisymmetric domains using ANSYS FLUENT 15 (R) commercial software. For turbulence modeling, shear stress transport (SST) k-omega model is preferred after a comparison of performance with the other available turbulence model options. The resulting model provides consistent pressure and flow rate estimations with CFD analyses and a smooth transition between different geometrical conditions. The ultimate aim of this study is to fulfill the need for a model to precisely determine the geometrical tolerances of spool valve components for optimum performance. Estimations of the developed model is compared with the experimental data of a spool valve, and the model is proved to be able to accurately estimate the maximum leakage flow rate, the pressure sensitivity, and the shapes of leakage flow/load pressure curves.
Subject Keywords
Control and Systems Engineering
,
Mechanical Engineering
,
Instrumentation
,
Information Systems
,
Computer Science Applications
URI
https://hdl.handle.net/11511/41491
Journal
JOURNAL OF DYNAMIC SYSTEMS MEASUREMENT AND CONTROL-TRANSACTIONS OF THE ASME
DOI
https://doi.org/10.1115/1.4041300
Collections
Department of Mechanical Engineering, Article
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A. C. Afatsun and R. T. Balkan, “A Mathematical Model for Simulation of Flow Rate and Chamber Pressures in Spool Valves,”
JOURNAL OF DYNAMIC SYSTEMS MEASUREMENT AND CONTROL-TRANSACTIONS OF THE ASME
, pp. 0–0, 2019, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/41491.