About the Influence of Eco-Friendly Fluids on the Performance of an External Gear Pump

Abstract

This paper wants to investigate the effects of eco-friendly fluids on the thermo-fluid-dynamic performance of external gear pumps in order to provide a first response to the increasingly urgent demands of the green economy. A computational fluid dynamics (CFD) approach based on the overset mesh technique was developed for the simulation of the full 3D geometry of an industrial pump, including all the characteristic leakages between components. A sensibility analysis of the numerical model with respect to different fluid properties was performed on a commonly used mineral oil, showing the key role of the fluid compressibility on the prediction of the pump volumetric efficiency. Moreover, the influence of temperature internal variations on both fluid density and viscosity were included. The BIOHYDRAN TMP 46 eco-friendly industrial oil and olive oil were further considered in this work, and the results of the simulations were compared for the three fluid configurations. A slightly lower volumetric efficiency was derived for the olive oil application against the other two conditions, but suggestive improvements were produced in terms of pressure and temperature distributions. Therefore, based on the obtained results, this paper encourages research activity towards the use of eco-friendly fluids in the hydraulic field.

A Computation Fluid Dynamics Methodology for the Analysis of the Slipper–Swash Plate Dynamic Interaction in Axial Piston Pumps

“…The physics continuum included an ISO VG 32 mineral oil [23], typically used in axial piston machines, and the fluid compressibility was considered as it significantly improves the predictive capability of the pumps' CFD models [24]. The variation in fluid density ρ with respect to the working pressure p is shown in (2), where ρ 0 represents the fluid density at the atmospheric pressure, while c is the speed of sound of the oil.…”

Development of a Numerical Approach for the CFD Simulation of a Gear Pump under Actual Operating Conditions

“…where κ is the turbulent kinetic energy; ω is the turbulent-specific dissipation rate; µ is the dynamic viscosity; µ t is the turbulent eddy viscosity; σ κ , σ ω , β, and β * are model coefficients; P κ and P ω are the productions terms; S κ and S ω are the user-specified source terms; f β is the vortex-stretching modification factor and f β * is the free-shear modification factor; and κ 0 and ω 0 are ambient turbulence values that counteract turbulence decay. For the morphing case, consistent with many cases in the literature [4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20], a κ-ε model is used. In the present case, the realizable κ-ε model was used [21], which adds the implementation of a new transport equation for the turbulent dissipation ratio ε, so that a variable damping function (expressed as a function of turbulence properties and mean flow) is applied to a critical model coefficient in order to satisfy mathematical constraints on the normal stresses consistent with the physics of turbulence, which is defined as realizability, especially to the near wall boundaries.…”

“…One is the overset meshing method, which does not require any external code as it is fully automated in the software and based on the interaction between distinct regions. The authors previously implemented this method in [10,11] and also successfully in a simulation of an EGP in [12]. The other method used is the classic dynamic meshing method, which exploits enhancements to conservation in the solution interpolation algorithm.…”

Parametric Optimization of a New Gear Pump Casing Based on Weight Using a Finite Element Method

“…Gear pumps are positive displacement type pumps. Gear pumps are generally used to pump liquids with high viscosity: fuel oils, oils, lubricating oils, paints, acids and alkalis, alcohols, and solvents [3][4][5]. In a gear pump, the rotation of the pump is transmitted by the drive gear [6].…”