Design, system modeling and energy management for a novel hydraulic pumping unit

2021 ◽  
pp. 095965182110043
Author(s):  
Zhenhe Li ◽  
Zhicheng Wang ◽  
Changjian Zhi ◽  
Daxiang Zhang ◽  
Xianchen Song ◽  
...  
Keyword(s):  
Solar Wind ◽  
Energy Management ◽  
Constant Speed ◽  
Total Power ◽  
Design System ◽  
Small Scale ◽  
Hydrostatic Transmission ◽  
Pumping Unit ◽  
Save Energy ◽  
Pumping Units

Compared to conventional pumping units with low efficiencies and general hydraulic pumping units using hydraulic accumulators to recover and reuse energy, this article presents a novel multi-source hydraulic pumping unit with the symmetrical structure in order to save energy. First, the balanced mechanical structure through the symmetrical arrangement of double wells can not only decrease the total power of the system significantly but also make the power consumption of the pumping unit drop substantially in the constant speed phase. Uniquely, the proposed pumping unit is jointly driven by a hydrostatic transmission hydraulic system and a small-scale solar–wind hybrid power generation system. The hydrostatic transmission technique enables the system power output to adapt to the load requirements in real time without extra throttling and overflow losses, while the solar–wind hybrid system drives alone in the constant speed phase to save energy and bring environmental benefits. After parameter analyses and calculations, the energy-saving advantage of the proposed system is displayed when compared to a counterpart. Then, the mathematical model of the system is developed, and the rule-based energy management strategy is designed for the energy distribution of the proposed system. The simulation results verify that the feasibility and reasonableness of the proposed system.

Non-Gaussian probability distributions of solar wind fluctuations

1994 ◽  
Vol 12 (12) ◽  
pp. 1127-1138 ◽  
Author(s):  
E. Marsch ◽  
C. Y. Tu
Keyword(s):  
Solar Wind ◽  
Probability Distributions ◽  
Time Lag ◽  
Small Scale ◽  
Time Lags ◽  
Mhd Turbulence ◽  
Theoretical Concepts ◽  
Fluid Turbulence ◽  
Long Time ◽  
Non Gaussian

Abstract. The probability distributions of field differences ∆x(τ)=x(t+τ)-x(t), where the variable x(t) may denote any solar wind scalar field or vector field component at time t, have been calculated from time series of Helios data obtained in 1976 at heliocentric distances near 0.3 AU. It is found that for comparatively long time lag τ, ranging from a few hours to 1 day, the differences are normally distributed according to a Gaussian. For shorter time lags, of less than ten minutes, significant changes in shape are observed. The distributions are often spikier and narrower than the equivalent Gaussian distribution with the same standard deviation, and they are enhanced for large, reduced for intermediate and enhanced for very small values of ∆x. This result is in accordance with fluid observations and numerical simulations. Hence statistical properties are dominated at small scale τ by large fluctuation amplitudes that are sparsely distributed, which is direct evidence for spatial intermittency of the fluctuations. This is in agreement with results from earlier analyses of the structure functions of ∆x. The non-Gaussian features are differently developed for the various types of fluctuations. The relevance of these observations to the interpretation and understanding of the nature of solar wind magnetohydrodynamic (MHD) turbulence is pointed out, and contact is made with existing theoretical concepts of intermittency in fluid turbulence.

scholarly journals Improving the Efficiency of Gas Pumping Units: Problems and Solutions

2019 ◽  
pp. 104-118
Author(s):  
E.M. Komarov ◽  
Zh.M. Kokueva
Keyword(s):  
Gas Turbine ◽  
Problems And Solutions ◽  
Pumping Unit ◽  
Gas Pumping ◽  
Gas Pumping Unit ◽  
Pumping Units ◽  
Turbine Drive

The paper describes the process of initiating a project to improve the efficiency of gas turbine plants for driving centrifugal superchargers at compressor stations. The study shows the main trends of increasing the efficiency of gas turbine drives of gas pumping units, gives the constructive-functional appearance of the modern gas turbine drive of the gas pumping unit, and proposes a method for increasing its efficiency.

scholarly journals Magnetosheath-cusp interface

2004 ◽  
Vol 22 (1) ◽  
pp. 183-212 ◽  
Author(s):  
S. Savin ◽  
L. Zelenyi ◽  
S. Romanov ◽  
I. Sandahl ◽  
J. Pickett ◽  
...  
Keyword(s):  
Boundary Layer ◽  
Solar Wind ◽  
Magnetic Fields ◽  
Large Scale ◽  
Traditional Approach ◽  
Qualitative Difference ◽  
Small Scale ◽  
Nonlinear Phenomena ◽  
Solar Wind Interaction ◽  
Linear Superposition

Abstract. We advance the achievements of Interball-1 and other contemporary missions in exploration of the magnetosheath-cusp interface. Extensive discussion of published results is accompanied by presentation of new data from a case study and a comparison of those data within the broader context of three-year magnetopause (MP) crossings by Interball-1. Multi-spacecraft boundary layer studies reveal that in ∼80% of the cases the interaction of the magnetosheath (MSH) flow with the high latitude MP produces a layer containing strong nonlinear turbulence, called the turbulent boundary layer (TBL). The TBL contains wave trains with flows at approximately the Alfvén speed along field lines and "diamagnetic bubbles" with small magnetic fields inside. A comparison of the multi-point measurements obtained on 29 May 1996 with a global MHD model indicates that three types of populating processes should be operative: large-scale (∼few RE) anti-parallel merging at sites remote from the cusp; medium-scale (few thousandkm) local TBL-merging of fields that are anti-parallel on average; small-scale (few hundredkm) bursty reconnection of fluctuating magnetic fields, representing a continuous mechanism for MSH plasma inflow into the magnetosphere, which could dominate in quasi-steady cases. The lowest frequency (∼1–2mHz) TBL fluctuations are traced throughout the magnetosheath from the post-bow shock region up to the inner magnetopause border. The resonance of these fluctuations with dayside flux tubes might provide an effective correlative link for the entire dayside region of the solar wind interaction with the magnetopause and cusp ionosphere. The TBL disturbances are characterized by kinked, double-sloped wave power spectra and, most probably, three-wave cascading. Both elliptical polarization and nearly Alfvénic phase velocities with characteristic dispersion indicate the kinetic Alfvénic nature of the TBL waves. The three-wave phase coupling could effectively support the self-organization of the TBL plasma by means of coherent resonant-like structures. The estimated characteristic scale of the "resonator" is of the order of the TBL dimension over the cusps. Inverse cascades of kinetic Alfvén waves are proposed for forming the larger scale "organizing" structures, which in turn synchronize all nonlinear cascades within the TBL in a self-consistent manner. This infers a qualitative difference from the traditional approach, wherein the MSH/cusp interaction is regarded as a linear superposition of magnetospheric responses on the solar wind or MSH disturbances. Key words. Magnetospheric physics (magnetopause, cusp, and boundary layers) – Space plasma physics (turbulence; nonlinear phenomena)

MHD and Ion Kinetic Waves in Field-aligned Flows Observed by Parker Solar Probe

2021 ◽  
Vol 922 (2) ◽  
pp. 188
Author(s):  
L.-L. Zhao ◽  
G. P. Zank ◽  
J. S. He ◽  
D. Telloni ◽  
L. Adhikari ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Solar Wind ◽  
Whistler Wave ◽  
Spectral Energy ◽  
Small Scale ◽  
The Sun ◽  
Fast Mode ◽  
Magnetic Fluctuations ◽  
Background Magnetic Field ◽  
Ion Cyclotron

Abstract Parker Solar Probe (PSP) observed predominately Alfvénic fluctuations in the solar wind near the Sun where the magnetic field tends to be radially aligned. In this paper, two magnetic-field-aligned solar wind flow intervals during PSP’s first two orbits are analyzed. Observations of these intervals indicate strong signatures of parallel/antiparallel-propagating waves. We utilize multiple analysis techniques to extract the properties of the observed waves in both magnetohydrodynamic (MHD) and kinetic scales. At the MHD scale, outward-propagating Alfvén waves dominate both intervals, and outward-propagating fast magnetosonic waves present the second-largest contribution in the spectral energy density. At kinetic scales, we identify the circularly polarized plasma waves propagating near the proton gyrofrequency in both intervals. However, the sense of magnetic polarization in the spacecraft frame is observed to be opposite in the two intervals, although they both possess a sunward background magnetic field. The ion-scale plasma wave observed in the first interval can be either an inward-propagating ion cyclotron wave (ICW) or an outward-propagating fast-mode/whistler wave in the plasma frame, while in the second interval it can be explained as an outward ICW or inward fast-mode/whistler wave. The identification of the exact kinetic wave mode is more difficult to confirm owing to the limited plasma data resolution. The presence of ion-scale waves near the Sun suggests that ion cyclotron resonance may be one of the ubiquitous kinetic physical processes associated with small-scale magnetic fluctuations and kinetic instabilities in the inner heliosphere.

Display Energy Management based on Eye Tracking

2012 ◽  
pp. 350-365
Author(s):  
Vasily G. Moshnyaga
Keyword(s):  
Energy Consumption ◽  
Energy Management ◽  
Personal Computer ◽  
Experimental Evaluation ◽  
The Other ◽  
Single Camera ◽  
Management Technology ◽  
Personal Computer System ◽  
Software And Hardware ◽  
Save Energy

With the explosive use of personal computers or PCs, reducing computer energy consumption is paramount for sustainability. The display is the largest energy consumer in a personal computer. Current display energy management technologies ignore the attention of the PC user and therefore may either switch the display off when the user looks at the screen or lose energy by keeping the display on when nobody looks at it. This chapter discusses a new display energy management technology and outlines its implementation in a personal computer system. Unlike existing technologies, which “sense” a PC user through keyboard and/or mouse or the other sensors, this technology “watches” the user through a single camera or CMOS vision sensor. The technology tracks the user’s eyes, keeping display active only if the user looks at its screen. Otherwise, it dims the display down or even switches it off to save energy. The authors implemented the technology in software and hardware and present the results of their experimental evaluation.

scholarly journals Solar cycle changes in the geo-effectiveness of small-scale solar wind turbulence measured by Wind and ACE at 1 AU

2007 ◽  
Vol 25 (5) ◽  
pp. 1183-1197 ◽  
Author(s):  
M. L. Parkinson ◽  
R. C. Healey ◽  
P. L. Dyson
Keyword(s):  
Solar Wind ◽  
Solar Cycle ◽  
Solar Minimum ◽  
Large Scale ◽  
Small Scale ◽  
Scaling Exponent ◽  
Mhd Turbulence ◽  
Scaling Exponents ◽  
Solar Wind Turbulence ◽  
Wind Turbulence

Abstract. Multi-scale structure of the solar wind in the ecliptic at 1 AU undergoes significant evolution with the phase of the solar cycle. Wind spacecraft measurements during 1995 to 1998 and ACE spacecraft measurements during 1997 to 2005 were used to characterise the evolution of small-scale (~1 min to 2 h) fluctuations in the solar wind speed vsw, magnetic energy density B2, and solar wind ε parameter, in the context of large-scale (~1 day to years) variations. The large-scale variation in ε most resembled large-scale variations in B2. The probability density of large fluctuations in ε and B2 both had strong minima during 1995, a familiar signature of solar minimum. Generalized Structure Function (GSF) analysis was used to estimate inertial range scaling exponents aGSF and their evolution throughout 1995 to 2005. For the entire data set, the weighted average scaling exponent for small-scale fluctuations in vsw was aGSF=0.284±0.001, a value characteristic of intermittent MHD turbulence (>1/4), whereas the scaling exponents for corresponding fluctuations in B2 and ε were aGSF=0.395±0.001 and 0.334±0.001, respectively. These values are between the range expected for Gaussian fluctuations (1/2) and Kolmogorov turbulence (1/3). However, the scaling exponent for ε changed from a Gaussian-Kolmogorov value of 0.373±0.005 during 1997 (end of solar minimum) to an MHD turbulence value of 0.247±0.004 during 2003 (recurrent fast streams). Changes in the characteristics of solar wind turbulence may be reproducible from one solar cycle to the next.

scholarly journals Ultrahigh-resolution model of a breakout CME embedded in the solar wind

2018 ◽  
Vol 620 ◽  
pp. A57 ◽  
Author(s):  
S. Hosteaux ◽  
E. Chané ◽  
B. Decraemer ◽  
D.-C. Talpeanu ◽  
S. Poedts
Keyword(s):  
Solar Wind ◽  
Adaptive Mesh Refinement ◽  
Flux Rope ◽  
Adaptive Mesh ◽  
Electrical Current ◽  
Substantial Effect ◽  
Small Scale ◽  
Release Process ◽  
Ultrahigh Resolution ◽  
Current Sheets

Aims. We investigate the effect of a background solar wind on breakout coronal mass ejections, in particular, the effect on the different current sheets and the flux rope formation process. Methods. We obtained numerical simulation results by solving the magnetohydrodynamics equations on a 2.5D (axisymmetric) stretched grid. Ultrahigh spatial resolution is obtained by applying a solution adaptive mesh refinement scheme by increasing the grid resolution in regions of high electrical current, that is, by focussing on the maximum resolution of the current sheets that are forming. All simulations were performed using the same initial base grid and numerical schemes; we only varied the refinement level. Results. A background wind that causes a surrounding helmet streamer has been proven to have a substantial effect on the current sheets that are forming and thus on the dynamics and topology of the breakout release process. Two distinct ejections occur: first, the top of the helmet streamer detaches, and then the central arcade is pinched off behind the top of the helmet streamer. This is different from the breakout scenario that does not take the solar wind into account, where only the central arcade is involved in the eruption. In the new ultrahigh-resolution simulations, small-scale structures are formed in the lateral current sheets, which later merge with the helmet streamer or reconnect with the solar surface. We find that magnetic reconnections that occur at the lateral breakout current sheets deliver the major kinetic energy contribution to the eruption and not the reconnection at the so-called flare current sheet, as was seen in the case without background solar wind.

scholarly journals ANALISIS PENGARUH INTERKONEKSI DISTRIBUTED GENERATION (PLTSA SUWUNG) TERHADAP RUGI-RUGI DAYA DAN KEANDALAN PADA PENYULANG SERANGAN

2015 ◽  
Vol 14 (2) ◽  
pp. 27
Author(s):  
I Made Gusmara Nusaman ◽  
I Wayan Sukerayasa ◽  
Rukmi Sari Hartati
Keyword(s):  
Distributed Generation ◽  
Power Plants ◽  
Flow Analysis ◽  
Ocean Waves ◽  
Load Flow ◽  
Ocean Current ◽  
Total Power ◽  
Small Scale ◽  
Renewable Energy Resources ◽  
Power Losses

The distributed generation technology or in this case abbreviated DG is a kind of power plants with small scale which prioritizes the utilization of renewable energy resources such as wind, water, solar, geothermal, ocean waves (Wave Energy), ocean currents (Ocean Current Energy), biomass, and biogass to produce the electrical energy with range of power generation between 1 kW-10 MW. One of the DG in Bali and still in operation is the garbage power plant which located in Suwung, South Denpasar. An analysis has been done using load flow analysis and reliability assessment to determine the effect of DG interconnection against the power losses and the level of reliability on the Serangan feeder. Based on the research that has been done, DG intercon-nection on the Serangan feeder decrease the power losses and increase the reliability and it can visible from the acquisition of SAIFI and SAIDI index which decreased. The best location of DG interconnection to get low of the power losses and the high level of reliability is at 97% from the total length of the feeder. At that location the power losses is decrease as big as 4.5 kW or 11.25% of the total power lossess without the DG interconnection and decrease of the SAIFI and SAIDI index respectively to 0.1 failure/customers/year and 1.4150 hour/ customer/year

scholarly journals Helioseismology from space, the SOHO project

1988 ◽  
Vol 123 ◽  
pp. 545-548
Author(s):  
V. Domingo
Keyword(s):  
Solar Wind ◽  
Solar Corona ◽  
European Space Agency ◽  
Science Research ◽  
Small Scale ◽  
Heliospheric Observatory ◽  
Space Agency ◽  
Cluster A ◽  
Physics Programme

As a cornerstone of its long term plan for space science research, the European Space Agency (ESA) is developing the Solar Terrestrial Physics Programme that consists of two parts: one, the Solar and Heliospheric Observatory (SOHO) for the study of the solar internal structure and the physics of the solar corona and the solar wind, and another, CLUSTER, a series of four spacecraft flying in formation to study small scale plasma phenomena in several regions of the magnetosphere and in the near Earth solar wind. The feasibility of the missions was demonstrated in Phase A studies carried out by industrial consortia under the supervision of ESA (1,2). According to the current plans an announcement of opportunity calling for instrument proposals will be issued by ESA during the first quarter of 1987. It is foreseen that the spacecraft will be launched by the end of 1994.

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