Characteristic Curves of Chemical Pump

The paper reports investigation variable speed Chemical pump Characteristic which includes flow, pressure, and power consumed and pump efficiency under condition of atmospheric pressure and temperature in Shuwaikh Kuwait. The experimental procedure will run on G.U.N.T Water system which permits the determination of characteristic curves –of a centrifugal pump by change the flow rate using a globe control valve. Digital displays show the speed and the electrical power consumption of the pump, the volumetric flow is shown by Rota meter the pressure reading from the suction and delivery pressure gauges. The results from the water system are compatible with that from experimental calculations with 5 % deviation, which mean that the system is appropriateness.

Numerical Investigation of a Globe Control Valve and Estimating its Loss Coefficient at Different Opening States

One of the most important components of fluid transmission systems is a control valve located in the pipelines of oil, gas, etc. The primary purpose of this valve is to control the rate of fluid flow passing through it under pressure changes and the most important issue is to investigate the flow’s characteristics in order to achieve a proper geometry to control the flow rate and pressure as desired. The valves used in pipelines add to the overall head loss of the system. Therefore, valves with proper geometry can reduce these minor losses and finally decrease total energy losses. In this paper, a globe control valve is modeled and then numerically investigated to extract its functional relation, which relates pressure ratio to inlet Reynolds number, and estimate its loss coefficient at the valve’s different opening states which have not been addressed completely before and can be beneficial for the selection and usage of globe valves under certain conditions. According to the results, it is found that pressure ratio and loss coefficient are functions of inlet velocity and the valve’s opening state’s percentage, which are directly related to the valve’s geometry. When the valve opens, the rate of change in pressure ratio and loss coefficient are very sharp. Gradually, this rate decreases and the results tend to the final value at the valve’s fully opened state.

Aeroacoustics Analysis of Globe Control Valves

Flow-induced noise in control valves is one of the greatest challenges faced by several industries and commonly used flow control device in process industries is globe control valves (GCV). In the present work numerical analysis was performed to study aeroacoustics of globe control valve. Axisymmetric globe control valve (2.54 cm) was analysed numerically using 2D large eddy simulation (LES) turbulence model for different valve openings. The Ffowcs-Williams and Hawkings (FWH) model was used to model the aero-acoustic. The fluid medium in the valve is air. It was observed that the sound pressure level (SPL) decreases with increase in the opening of the valve. The modification in the design of the control valve was considered to reduce SPL without affecting the inherent characteristic, flow coefficient (Cv). The design modifications in the control valve considered were chamfering the seat and filleting the plug of the valve. Out of these modifications, the 20° chamfer to the inlet side of seat gave the least sound pressure level for the various openings of the globe control valve.

Predicting Globe Control Valve Performance—Part I: CFD Modeling

Computational Fluid Dynamics (CFD) tools are evaluated for use in industrial design applications by predicting primary control valve performance characteristics. The performance parameter of primary interest to the manufacturer is the flow coefficient, Cv. Valves having relative valve capacity factors between 2.5 and 13 were modeled. The control valve Cv was experimentally measured and numerically predicted. Both equal percentage and linear characteristic valves were represented in the study. The numerical (simulation) study presented in Part 1 showed that the valve Cv and the inherent valve characteristic could be accurately predicted using axisymmetric flow models over most of the plug travel. In addition, the study demonstrates the usefulness of simplified CFD analysis for relatively complex 3-D flows.

Predicting Globe Control Valve Performance—Part II: Experimental Verification

An experimental study was undertaken to verify an axisymmetric numerical model of a control valve flow field. The numerical model, which utilized Computational Fluid Dynamics (CFD), was formerly developed to be used as a design tool by manufacturers of control valves. In this work the model was first tested by comparing its results to data taken on an axisymmetric flow field experiment. Then the model’s application to actual three-dimensional control valves was tested by studying the pressure and flow field through a three-dimensional control valve. The results showed that the axisymmetric numerical model is accurately modeling an axisymmetric flow field. In addition, the results showed that control valves have a predominantly axisymmetric flow field for most of their plug travel which make them suitable for the model. Finally, the results showed details about the flow field such as where separation and reattachment may occur.