The paper refers to the numerical analysis of the internal flow in a hydraulic cross-flow turbine type Banki. A 3D-CFD steady state flow simulation has been performed using ANSYS CFX codes. The simulation includes nozzle, runner, shaft, and casing. The turbine has a specific speed of 63 (metric units), an outside runner diameter of 294 mm. Simulations were carried out using a water-air free surface model and k-εturbulence model. The objectives of this study were to analyze the velocity and pressure fields of the cross-flow within the runner and to characterize its performance for different runner speeds. Absolute flow velocity angles are obtained at runner entrance for simulations with and without the runner. Flow recirculation in the runner interblade passages and shocks of the internal cross-flow cause considerable hydraulic losses by which the efficiency of the turbine decreases significantly. The CFD simulations results were compared with experimental data and were consistent with global performance parameters.

A 3D-CFD simulation of the impeller and volute of a centrifugal pump has been performed using CFX codes. The pump has a specific speed of 32 (metric units) and an outside impeller diameter of 400 mm. First, a 3D flow simulation for the impeller with a structured grid is presented. A sensitivity analysis regarding grid quality and turbulence models were also performed. The final impeller model obtained was used for a 3D quasi-unsteady flow simulation of the impeller-volute stage. A procedure for designing the volute, the nonstructured grid generation in the volute, and the interface flow passage between the impeller and volute are discussed. This flow simulation was carried out for several impeller blades and volute tongue relative positions. As a result, velocity and pressure field were calculated for different flow rates, allowing to obtain the radial thrust on the pump shaft.

No abstract

No abstract

No abstract

No abstract

Despite their low efficiency compared with centrifugal pumps, jet-pumps are highly reliable robust equipment with modest maintenance which is ideal for many applications, mostly in the oil & gas industry. For example, jet-pumps could result attractive compared to other multiphase pump systems in terms of reactivating transport lines of heavy crude oil. Nevertheless, their design method and performance analysis are rarely known in the literature and keep a high experimental component like most of the pumping equipment. Starting with a pump designed by a traditional method, this paper aims to evaluate the effect of multiple geometrical and operational variables that influence the jet-pump performance combining CFD (Computational Fluid Dynamics) simulation and optimization algorithms using commercials software (ANSYS CFX® and PIPEIT® tool). Automatically, the geometric parameters are modified according to the rules of the optimization routines seeking to maximize the flow capacity, respecting restrictions such as energy consumption. A case study is presented for the preliminary design of a pump to boost flow capacity in a trunk line of a heavy oil field. As preliminary design all simulations were carried out using single phase water flow. With this method, it was possible to quickly evaluate around 400 geometries of jet-pumps. The geometry of the optimum final pump is consistent with other pumps reported by other works. This pump enhances the fluid capacity of the line in 17% over the traditional design for the same parameters of power or consumed energy.

This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.