Parallel Pumping Research Articles

Efficiency Increase in Water Transmission Systems Using Optimized Selection of Parallel Pumps Running as Turbines

AbstractWater transmission lines have considerable hydraulic potential that can be used in hydropower plants to produce energy. The pump as turbine (PAT) is an applicable tool that provides accepta...

Improving energy efficiency of individual centrifugal pump systems using model-free and on-line optimization methods

Pump systems around the world account for a high percentage of electrical energy consumption. The energy efficiency of these systems can be improved using control algorithms to determine appropriate operating points. The problem that arises is that computed operating points deviate from real operating points. This is due to deviations of the affinity laws, inaccurate information about pump characteristics, and plant behavior. In order to address this problem, we will present model-free optimization methods that can optimize various pump systems during ongoing operation. First, we will classify different pump systems. Based on this categorization, we will then analyze characteristic systems with regard to their energetic optimum. The resulting findings will enable us to identify suitable optimization algorithms. These model-free optimization algorithms take the form of an extremum seeking control in combination with a Kalman filter, the Nelder Mead algorithm, and a dynamic optimization method. After describing these algorithms, we will optimize and validate three sample classes of pump systems using the respective appropriate optimization strategy. The three classes represent a single-pump system, a multiple parallel pump system and a pump storage system. We can see that all optimization strategies achieve the energetic optimum. We can identify savings of between 7.9% and 50%, depending on the system in question. Finally, we will present a best-fit model-free optimization strategy for each class, and system operators can employ this strategy to ensure energy-optimized operation of their specific system.

Research on Parallel Operation Characteristics of High-pressure Pumps Applied in Coal Mine Hydraulics permeability improvement

Nowadays, plunger high-pressure water pumps applied in large-scale mine are mostly used in coal mine hydraulics to increase permeability, and it is difficult to transport objections underground. Besides, the permeability improvement is affected during overhaul too. Therefore, multiple small high-pressure water pumps operating in parallel can be used to solve the problems mentioned above instead of large high-pressure water pumps. Moreover, the operating principle of the plunger high-pressure pump determines the specific flow fluctuation characteristics during its operation, and similar flow fluctuations also exist during the operating of parallel pump sets. The transmission model and AMESim hydraulic simulation model of single, parallel plunger pumps are established, taking the BQW-22/50 high-pressure water pump as an example. The operating characteristics of a single plunger pump and a parallel pump group are analyzed in this paper. The results are obtained as follows: the instantaneous discharge flow curve of a single plunger pump conforms to a sine function; the flow of the parallel pump set is the superposition of the flow of multiple plunger pumps; the instantaneous discharge flow curve changes under the influence of the phase deviation angle between the pumps; when parallel pump sets are running, there is an optimal phase deflection angle between the pumps, which minimizes the flow fluctuation of the pump sets; when four high-pressure water pumps are operated in parallel, the optimal phase deflection angle between the pumps is π/12 or π/4.

The Manufacturing Planning of Installation Series-Parallel Combination Centrifugal Pump Testing Equipment

This study discusses the planning in making a centrifugal pump installation with a combination of two series, namely series and parallel. The concept of discussion refers more to the upgrading of the installation system and calculates the estimated processing time needed to test the performance of the results of the installation that has been made. From the results of the research, it was found that for the preparation of series series installation it takes ± 8.5 minutes including the cutting process of materials and component installation, while the time required in making the installation of parallel circuits ± 28 minutes so that the total manufacturing of the two types of series takes 36, 5 minutes. In terms of performance generated from each installation obtained at full aperture where for the series of head series the value obtained is 37.6 m with a flow capacity of 3.25 l / s while for the head value on the parallel pump obtained by 27.7 m with a capacity flow of 3.75 l / s and this pump operates at 2900 rpm. So it can be seen from the results of the head and flow capacity obtained values ​​indicate good pump performance and ready to be used as a practical tool in the laboratory.

Watt-Level ~3.5 μm Er³⁺-Doped ZrF₄ Fiber Laser Using Dual-Wavelength Pumping at 655 and 1981 nm

In this letter, we propose a parallel dual-wavelength pumping (DWP) method (655 nm + 1981 nm) to realize high power output from a Er <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3+</sup> -doped ZrF <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">4</sub> fiber laser at ~ 3.5 μm, for the first time, to the best of our knowledge. This laser can emit a maximum power of 1.72 W, where the slope efficiency with respect to the launched 1981 nm pump is 31.5%. Further power scaling is mainly limited by the available 1981 nm pump power. Direct comparison with the common cascade DWP method (976 nm + 1981 nm) is performed. The results indicate that the parallel DWP method allows a larger output power at a certain 1981 nm pump power, thus providing another promising way for power scaling at this band.

Anisotropic optical gains in a-plane ZnO/Zn0.8Mg0.2O multiple quantum wells grown via pulsed-laser deposition

High periodicity non-polar ten-pair ZnO/Zn0.8Mg0.2O multiple quantum wells (MQWs), with a binding energy of approximately 69.8 meV, on r-plane sapphire were prepared via pulsed-laser deposition. The a-plane ZnO/Zn0.8Mg0.2O MQWs exhibit anisotropic optical properties, which demonstrate an energy difference of approximately 15 meV between the two splitting valence bands via photoluminescence measurement.Through the optical pump of the Q-switched laser, the amplified spontaneous emission (ASE) from both the side and surface normal of the non-polar MQWs shows a higher slope efficiency and gain coefficient under a perpendicular pump (Ep⊥c) than those under a parallel pump condition (Ep//c). Owing to the gain-guiding effect, the linealy polarized ASE from the side of the non-polar ZnO/Zn0.8Mg0.2O MQWs has been demonstrated with a degree of polarization (DOP) ~ 89 %. For the surface normal ASE, the P2 band emission from exciton–exciton (ex-ex) scattering is recognized as the dominant mechanism. Through the temperature-dependent ASE, the P band emission peak reveals an evident red shift as the temperature increases. Moreover, a higher characteristic temperature of ~ 124 K, which indicates the temperature-insensitive property, is obtained.

Increasing Service Life and System Efficiency of Parallel Pumps Using Combined Pump Regulation

The paper discusses the use of the combined control for a system of two parallel pumps to increase its service life. Using the combined control, the pumping system is controlled together by change the speed, throttling, and bypass. The power consumption of the pumping system is calculated for three methods of flow control: with minimum energy consumption, with maximum reliability, and control with a trade-off between efficiency and reliability. In the case of control with maximum reliability, the energy consumption of the pumping system is higher than in the case of control with minimum energy consumption by 29.2%. In the case of the proposed trade-off control, which provides acceptable reliability, the power consumption is higher than with the minimum energy consumption control by only 7.3%.

Research on polarization insensitive AOWC system for 40Gbps 16QAM-OFDM based on wide optical comb generation self-pumping structure

In this paper, we proposed a 40Gbps 16QAM-OFDM polarization insensitive all-optical wavelength conversion (AOWC) system based on self-pumping structure of wide optical comb. In this scheme, the carrier suppression modulation is carried out by a laser with Mach-Zehnder modulator (MZM) to generate a wide comb with only 3 dB odd sidebands flatness. By changing the frequency selection of the optical comb, the signal light and two pump lights are generated by the system itself. The analytical results show that the frequency selection of the optical comb and comb flatness can affect the performance of the system. The smaller the frequency interval among three lights selected as signal light and two pump lights are, the smoother the comb is, the better the system performance is. We have also numerically demonstrated that the system performance is best when the frequency interval is minimum, and with the increase of flatness, the system performance gradually decreases. The simulation results can be agreed with the theoretical analyses, the constellation of 40 Gb/s 16QAM-OFDM signal can be seen clearly and the bit error rate of the system can up to 1.26×10- 4. In addition, the effects of injection current of SOA and linewidth of continuous wave (CW) on system performance are also discussed. The proposed system can be a candidate to realize polarization insensitive by the parallel pump lights and signal light from this self-pumping structure, it has the characteristic that the amplitude phase noise conversion can be neglected.

Improving Reliability and Energy Efficiency of Three Parallel Pumps by Selecting Trade-Off Operating Points

Reliability, along with energy efficiency, is an important characteristic of pump units in various applications. In practical pump applications, it is important to strike a balance between reliability and energy efficiency. These indicators strongly depend on the applied control method of the pump unit. This study analyzes a trade-off method for regulating a system with three parallel pumps equipped with only one frequency converter (multi-pump single-drive system). A typical operating cycle of a pumping system with variable flow rate requirements is considered. The proposed trade-off method is compared with the traditional regulation, when a change in the operating point of the pump is achieved only by changing the rotation speed, and with the method for maximum reliability. It is shown that the proposed trade-off method makes it possible to ensure sufficient reliability of the multi-pump system operation without a significant increase in energy consumption.

Numerical Investigation of Water Hammer due to Transient in Parallel Pumps

Numerical Investigation of Water Hammer due to Transient in Parallel Pumps

Effects of ambient conditions on solar assisted heat pump systems: a review.

Solar assisted heat pump (SAHP) systems aim to increase the performance of heat pumps by supporting with solar energy using various heating modes, whose performances depend on ambient conditions. In the literature, SAHP systems are classified by structure types, and the heating mode options are not considered as the main priority of the design but a result of the structure of the system. This paper aimed to investigate the effect of ambient conditions on heating modes, and identify the preferable ambient condition ranges for each SAHP system depends on their heating modes, by using a narrative review of 47 recent studies, that shed light on the problem. For this purpose, direct solar heating (DSH), air source heat pump (ASHP), solar source heat pump (SSHP) and solar-air source heat pump (S/ASHP) modes were stated as the basic heating modes of SAHP systems. In accordance with the literature, SAHP systems were classified as direct expansion solar assisted heat pump (DX-SAHP) and series, parallel and dual source indirect expansion solar assisted heat pumps (IDX-SAHP). Solar irradiation, ambient temperature, relative humidity and wind speed has been taken as major ambient conditions to investigate. Reviewed studies indicated that, parallel and series IDX-SAHP are preferable in high solar irradiations about 800W/m2 with their DSH mode options. Frosting on evaporator is prevented in DX-SAHP with its S/ASHP mode, and even in the presence of frosting, unlike IDX-SAHPs ASHP mode, freezing is a factor that improves performance on flat evaporator in cold and humid conditions. This study indicates that there are obscure areas for future studies to focus on for a better comparison between SAHP types. Moreover, proposed novel designs of this paper, such as solar preheating of air in IDX-SAHP systems to add S/ASHP mode as an option, might enhance the performance and applicability of SAHP systems.

A distributed optimization algorithm for the dynamic hydraulic balance of chilled water pipe network in air-conditioning system

Aiming at the problem of the dynamic hydraulic balance regulation of chilled water pipe network in central air-conditioning system, a distributed iterative optimization algorithm is proposed based on the novel distributed control architecture and the alternating direction method of multipliers (ADMM) with regular term. Firstly, the total flow and the minimum water pressure difference between supply and return are calculated according to the flow demand of each air handling unit. Furthermore, based on the ADMM with regular term, the optimal operation of parallel pumps is accomplished. Finally, the dynamic hydraulic balance of chilled water pipe network is achieved with the minimum energy consumption, and the on-demand flow distribution is realized. After that, a central air-conditioning system is taken as an example to verify the performance of the proposed algorithm. Results show that the proposed algorithm is a distributed optimization algorithm with high precision, high stability and high energy saving. Compared with one strategy that is not optimized, the operation strategy optimized by the proposed algorithm can save energy about 28.54% while realizing the dynamic hydraulic balance of the pipe network.

A Method for Pump Manifold Performance Calculations in Hydraulic Air Compressors

Abstract Analytical methods are described that were developed to undertake the pump manifold calculations for hydraulic air compressors (HACs) where multiple pumps are installed in parallel configurations. The procedures are fast and exact and were developed for design optimization and control tasks which, although described in the specific context of HACs, are also applicable to more general pumping systems. The proposed method uses a recursive/iterative procedure to establish the pump curve equivalent to the pump combination so that the design performance of the system can be assessed for any value of externally attached hydraulic resistance. The technique is verified against a numerical method applied to the same problem, but where the external hydraulic resistance must be completely specified for a solution. Losses at convergent and divergent wyes, which are required to create the parallel pump manifold arrangements, are found to be significant factors in establishing the overall energy efficiency of the pumping system. With efficient pump manifold arrangements designed, a so-called binary pumping scheme is explained, where individual pumps in the manifold can be activated (1) or deactivated (0) so that the pumping system flow can be reduced with good turn-down ratios while ensuring that the best efficiency point (BEP) efficiency of the system is maintained (exemplified with 4:1 or 25%).

Parallel Computations Based Micromagnetic Solver and Analysis Tools for Magnon-Microwave Interaction Studies

The interaction of microwaves with magnetic materials gives rise to interesting and useful phenomena. The study of many such phenomena is, however, often complicated due to the nature of magnetic materials and/or the limitations in experimental techniques. In this work, we discuss the construction of a Landau Lifshitz Gilbert (LLG) equation-based micromagnetics solver using the parallel programming language- CUDA to study microwave-magnet interactions. The use of CUDA on Graphics Processing Units (GPUs) allows us to leverage the inherently parallel nature of the magnetic systems, thereby allowing large-scale (spatial and temporal) simulation-based studies that are otherwise unreasonable. In addition, computational techniques that allow a magnon-based interpretation of the physical processes are also introduced. Basic nonlinear magnonic phenomena, e.g., 3- and 4-magnon scattering and magnon growth dynamics, have been demonstrated. We show for the first time the direct excitation of magnons with nonzero wave-vectors in the context of parallel microwave pumping.

Gain‐flattened hybrid EDFA operating in C + L band with parallel pumping distribution technique

A novel C + L band hybrid erbium-doped fibre amplifier (EDFA) using a two-stage configuration was proposed and demonstrated experimentally. The amplifier is composed of a 0.5-m long hafnium bismuth erbium co-doped fibre (EDF) to provide gain within the C-band and a 4-m long zirconia-based EDF to provide gain within the L-band. The proposed amplifier was examined based on the multi-wavelength input source. A parallel pumping distribution technique was used to mitigate the amplifier complexity. The C + L band amplifier achieved a gain flattening of over 55 nm bandwidth for the three levels of the input powers. A gain-flattening of roughly 10.9, 15.5, and 19.2 dB were obtained, respectively, for the input signal powers of −5, −10, and −15 dBm. An average noise figure of 6.4, 5.4, and 4.7 dB was achieved, respectively, for the input signal powers of −5, −10, and −15 dBm.

Experimental Investigation of Piezoelectric Micropumps with Single, Series or Parallel Pump Chambers

Three types of piezoelectric micropumps following different configurations: single, series, and parallel connection, are developed and investigated. All the micropumps are fabricated by wet etching technology and sealed by high temperature glass bonding. They share the same dimension characteristic of diffuser/nozzle microchannels. Verifying the impact of adding series or parallel connected pump chambers on single chambers, as well as verifying the performance of the flow rate, pressure and piezoelectric transducer vibration of three micropumps have been examined. Through the comparisons between three kinds of micropumps, the results show that the flow rate of the micropumps with parallel connected pump chambers have a higher flow rate than that of micropumps with single and serial connected pump chambers under the same driving conditions. In addition, both the flow rate and pressure with the serial micropump are the lowest. The pressure of the micropump with single pump chamber is larger than other kinds of micropumps at certain driving frequencies. Consequently, increasing the pump chambers cannot always increase the performance of the micropump. This coincides with the theory analysis. Finally, the vibration performance of piezoelectric transducers with three micropumps have been carried out. The parallel transducer has a higher vibration displacement than the other two kinds of micropumps. These results have great potentials for integration into labs with a chip or microfluidic driven systems.

Optimizing Parallel Pumping Station Operations in an Open-Channel Water Transfer System Using an Efficient Hybrid Algorithm

This article presents a methodology for optimizing the operation of parallel pumping stations in an open-channel water transfer system. A mathematical model was established for the minimum power with constraints on water level, flow rate and pump unit performance, and related factors. In the objective function, energy consumption of relevant equipment or facilities, such as main pump units, power transmission and transformation equipment, and auxiliary equipment, was considered comprehensively. The model was decomposed to two layers for solving. In the first layer, by using discharge distribution ratio as a variable, the flow rate and water level of the two water channels could be determined by employing the dichotomy approach (DA), and were calculated according to the principle of energy conservation, considering energy loss caused by hydraulic leakage and evaporation losses. In the second layer, the number of running pumps and the flow rate of a single pump were obtained by simulated annealing–particle swarm optimization (SA–PSO). The hybrid of the two algorithms is called the dichotomy approach–simulated annealing–particle swarm optimization (DA–SA–PSO). To verify the efficiency and validity of DA–SA–PSO, SA–PSO is also applied to determine discharge distribution ratio. The results indicate that the computation time using DA–SA–PSO is 1/30 of that using double-layer SA–PSO (dSA–PSO). Compared with the original plan, the optimal solution could result in power savings of 14–35%. Thus, the DA–SA–PSO is highly efficient for optimizing system operation in real time.

Kajian Eksperimen Instalasi Pompa Seri dan Paralel Terhadap Efisiensi Penggunaan Energi

The pump is used to transfer liquid fluid from a low place to a high place or from one place to another with a certain distance and with a certain height. This study aims to figure the connection of series and parallel pumps to the discharge, pressure and pump power, and to figure the efficiency of series and parallel pumps with energy use. This study was conducted in a mechanical engineering major at Sambas State Polytechnic. The method used was three treatment experiments, including installing a single pump, a series pump installation, and a parallel pump installation. Observed changes are flow rate, water pressure, motor rotation, and electric current. The results showed that the series pump did not affect the discharge, but it affected the pressure and hydraulic power of the pump. While the parallel pump affects the increase in discharge but does not affect the pump pressure and hydraulic power. The results of pump calculations flow rate series 0.000450 m3 / sec, while the parallel pump flow rate 0.000769 m3 / sec. The results of pump measurement pressure are 80 psi series, while the parallel pump pressure is 40 psi. The calculation result of the hydraulic pump is 248.28 Watt series, while the parallel pump hydraulic power is 198.2 Watt. The power efficiency of series pumps is higher than the efficiency of parallel pumps. The efficiency of electric power when measuring flow rate at 70.53% series pump installations, parallel pump electrical power efficiency of 56.3%. The efficiency of electric power when measuring series water pressure is 45.14%, while the parallel pump's electrical power efficiency is 36.03%. Keywords: Efficiency, pump installation, series, parallel.

Controls of the modes of operation of the pumping station with application of frequency-controlled electric drive

The article describes the developed system of automatic control of technological process of water supply of a pumping station, providing mainly for potable, technical and circulating water supply stable maintaining constant the required pressure in their main delivery pipe when the probabilistic nature of water consumption through a smooth frequency start and further regulation of productivity and pressure develop any of the parallel pump units on the steps for power regulation.

An optimized control strategy for integrated solar and air-source heat pump water heating system with cascade storage tanks

By integrating non-concentrating solar collectors and air-source heat pumps (ASHP) in parallel, the water heating system with cascade storage tanks shows great potential for energy saving when the control strategy is well designed. In this study, a novel feedback control strategy is proposed for this system, in which the ON/OFF of ASHP connected to the heat storage tank (HST) is activated by comparing the tank temperature to a set of reference temperature curves that are functions of time. The reference temperature curves are established based on the operation scenarios of ASHP at HST, varying with seasonal environmental characteristics and users’ thermal demands. To illustrate the advantages and test the robustness of the proposed control strategy, the systems running with the different control strategies are studied for a residential building located in different climate conditions through TRNSYS simulation and experiments. The results show that as compared to the commonly-used “thermostatic” strategies, the proposed control strategy could keep HST water temperature at a lower level during the daytime, and increase the operation efficiencies of solar collectors and ASHP at HST, which maximize the solar energy harvest. Therefore, the working hours of ASHP are significantly shortened, and thus up to 26% of the annual energy consumption could be reduced. The results also show that the control strategy is more effective in the high irradiation zones. This study is significant because it provides design guidelines for the easy-to-operation control strategy of the integrated parallel solar thermal and ASHP water heating systems.