Complex Pumping System Research Articles

Mechano-hydraulic pumping solutions for reduction off energy losses in agricultural mobile machinery

Hydraulic digital power consists in a hydraulic plant having one or more discreet valued components actively with which we are controlling the system output flow. In this paper authors study a solution of 4 fixed pumps parallel connected. This complex pumping system can achieve 15 flows. The pumping system consists in an electrical single speed motor, 4 fixed pumps, the repartition will achieve with the help of 4 electrohydraulic distributors and an electronic micro-controller. The hydraulic plant was made in our Research Institute in the digital hydraulic laboratory for conducting tests and experiments.

Additively Manufactured Digital Microfluidic Platforms for Ion-Selective Sensing.

Digital microfluidic (DMF) sensors integrated with circuit systems have been applied to a broad range of applications including biology, medicine, and chemistry. Compared with the conventional microfluidic devices that require extra liquid as a carrier and a complex pumping system to operate, DMF is an ideal platform for ion-selective sensing as it enables the droplet operation in a discrete, accurate, and automatic way. However, it is quite rare that DMF platform is utilized for the ion-selective detection. In this paper, we report an integrated DMF system which combines DMF and ion-selective sensing for facile blending of multiple ions, and detection of targeted primary ion. The platform is fabricated through an additive manufacturing method, together with the real-time droplet's motion monitoring feedback system. Thus, the fabricated system demonstrates controlled droplet manipulation ability including droplet actuation, mixing, and speed control. Targeted primary ion is selectively detected under concentration range from 10-6 to 1 M. The interference study with blended ions has been investigated through on-chip ion selective membranes.

Particle focusing by 3D inertial microfluidics

Three-dimensional (3D) particle focusing in microfluidics is a fundamental capability with a wide range of applications, such as on-chip flow cytometry, where high-throughput analysis at the single-cell level is performed. Currently, 3D focusing is achieved mainly in devices with complex layouts, additional sheath fluids, and complex pumping systems. In this work, we present a compact microfluidic device capable of 3D particle focusing at high flow rates and with a small footprint, without the requirement of external fields or lateral sheath flows, but using only a single-inlet, single-outlet microfluidic sequence of straight channels and tightly curving vertical loops. This device exploits inertial fluidic effects that occur in a laminar regime at sufficiently high flow rates, manipulating the particle positions by the combination of inertial lift forces and Dean drag forces. The device is fabricated by femtosecond laser irradiation followed by chemical etching, which is a simple two-step process enabling the creation of 3D microfluidic networks in fused silica glass substrates. The use of tightly curving three-dimensional microfluidic loops produces strong Dean drag forces along the whole loop but also induces an asymmetric Dean flow decay in the subsequent straight channel, thus producing rapid cross-sectional mixing flows that assist with 3D particle focusing. The use of out-of-plane loops favors a compact parallelization of multiple focusing channels, allowing one to process large amounts of samples. In addition, the low fluidic resistance of the channel network is compatible with vacuum driven flows. The resulting device is quite interesting for high-throughput on-chip flow cytometry.

Genetic optimization and experimental verification of complex parallel pumping station with centrifugal pumps

While single pump design allows operation at high performance levels, multi-pumping systems are controlled to cover actual flow rate requirements, with less emphasis on power consumption. Widely accessible sensors and programmable controllers can improve this approach.This paper discusses the methodology for optimizing analysis of a complex pumping system with set of parallel centrifugal pumps. For this purpose, an experimental model pumping station, with four pumps in a parallel configuration, was designed and constructed. Auxiliary equipment allows control of each pump by three possible methods: (i) discharge valve, (ii) by-pass flow, and (iii) variable speed drive (VSD). For system performance optimization, three estimating strategies, that are functions of control input parameters at each pump were proposed: (i) minimization of power consumption, (ii) flow rate balancing and (iii) maximization of overall efficiency.A Uniquely developed (C++) genetic algorithm (GENOCOP) determined solutions and these were positively verified by measurements at the model experimental station. Results show the existence of multiple local extrema for all of estimating strategies. These solutions show it is possible to control a complex pumping station with various combinations of control parameters, giving similar results. This analysis demonstrates that the strategy of minimizing power consumption is the most energy efficient and proves the described methodology as a powerful tool for optimizing of complex pumping stations.

Tripping transients in a complex pumping system with multi pumps in parallel

The paper reports the analysis and application of a large scale pumping station with complex machinery, electrical, and hydraulic systems. The interaction between the pump system and transient flow in case of a sudden tripping of power to the system was investigated by numerically solving governing equations of multi pumps in parallel operation. The transient flow in the hydraulic system and the dynamics of the pumps, for example, oscillation of the surge tank, water hammer wave propagation, dynamical fluid torque acting on the pump impeller, and dynamical pump speed, were obtained on the complete pump model. Results obtained with the present approach show a promising reference for operation of a large scale pumping station with complex system in undulating case due to a sudden power tripping.

Fabrication and characterization of a passive silicon-based direct methanol fuel cell

This paper reports on the fabrication and characterization of a passive silicon microfabricated direct methanol fuel cell (μDMFC). The main characteristics of the device are its capability to work without complex pumping systems, only by capillary pressure, and the fact that its performance is not affected by the device orientation. A simple fabrication process based in deep reactive ion etching (DRIE), allows obtaining a reliable and low-cost final device. The device consists of two silicon microfabricated plates mounted together with a commercial membrane electrode assembly (MEA). The impact of current collector design on microfuel cell performance is explored and current–voltage (I–V) and current–power (I–P) curves of the device at different methanol concentration and orientation are presented. Optimal performance was obtained for methanol concentrations between 3 and 5 M, achieving a maximum power density of 12 mW/cm2. The results obtained in this work demonstrate the feasibility of the device and give a guideline for design and conditions optimization.

Calculating equivalent radial distances for determination of transmissivity and storativity using drawdown data from a multiple pumping well systems

Abstract A method is presented for the determination of aquifer transmissivity (T) and storativity (S), using distance-drawdown data from a wellfield with multiple pumping and observation wells. An equivalent radial distance calculated for each observation well, the aggregate system pumping rate (Q), and drawdown data for two or more nearby observation wells are used in the calculation of T and S. The method described can be used to evaluate complex pumping systems, as it can accommodate multiple pumping wells discharging at the same or at different rates, and varying well spacings. It can also accommodate a combination of both pumping and recharge wells concurrently operating. This versatile approach is particularly useful in determining the aquifer transmissivity and storativity for a series of extraction wells installed to remediate ground water, for use in subsequent capture zone and other design/performance evaluations. It is also useful for determining aquifer characteristics for evaluation of an operating water supply wellfield.

A distributed control and monitor system used in laser fusion research

Laser fusion research experiments require very low pressure environments to properly diagnose the plasma physics phenomena occurring during laser fusion reactions. Target chambers with very large and complex pumping systems are required to achieve and maintain these extremely low pressures. This paper describes a recently installed distributed control and monitoring system that automates the operation of these pumping systems. Through automation, this system is providing an enhanced shot rate by reducing the manpower required to ready the system for a target shot while increasing the overall safety of the system.

Mathematical Modeling of Landfill Gas Extraction

A model, incorporating Darcy’s law, is developed for single-species gas flow inside a nonisotropic porous medium, within which gas is continuously generated. A linear parabolic equation is derived to express the internal pressure variations in terms of the permeability, gas production rate, and boundary conditions of a site when a series of extraction wells are present. The model is used to determine the gas fluxes within a site of rectangular cross section, into which an arbitrary number of horizontal extraction pipes have been installed. This solution is used to predict the consequences of cumulative failures within a complex pumping system, and hence estimate the circumstances under which gas is first able to escape from a site. Using the results of the model some brief guidelines are offered for designing such installations. The analytical solution technique is contrasted with purely numerical methods for similar problems, and the speed and accuracy of each are compared. An efficient computer implementation for preliminary design studies is suggested.