基于智能算法的冷水机组优化运行研究

以南方某机场航站楼冷源系统为研究对象,采用深度神经网络建立了两种不同类型冷水机组的运行能效模型,并将冷却水出水温度模型与冷水机组能效模型进行耦合,以冷源系统能耗最低为目标,采用布谷鸟搜索算法优化了冷源系统的运行参数、冷水机组与冷却塔的组合方式。研究结果表明：采用深度神经网络建立的冷水机组模型具有较高的精度和泛化能力,与原运行方式对比,采用布谷鸟搜索算法优化的方法在夏季典型日最高节能19.6%,具有较高的节能效果。     

制冷机房群控系统的高效节能控制

通过上海卢湾区太平桥126项目制冷机房群控系统的高效节能控制方案的设计分析,阐述了通过群控优化系统进行冷水机组、冷冻水泵、冷却水泵、冷却塔的台数和变频控制,从而实现冷冻机房综合能耗最低,以保证制冷系统节能运行、集中管理和控制。     

组态软件在冷水机组实时监视与故障诊断方面的应用

先进行冷水机组监测参数的选择和数据采集的硬件配置,然后在MCGS组态软件的组态环境下进行组态工程的开发,组成冷水机组实时监视与故障诊断系统。该系统实现对冷水机组的运行参数实时监视、参数超限报警和故障人工智能诊断的功能;便于严密监视设备的运行工况,减少故障发生;也便于在设备发生故障后分析和判断故障产生的原因。     

低环境温度空气源冷水机组评价系统的研究

针对常规空气源冷水机组评价系统无法进行低环境温度空气源冷水机组的低环境温度制冷工况测试而设计了低环境温度空气源冷水机组评价系统,详细论述了该评价系统的测试原理、调节设备等关键性问题。在对低环境温度制冷工况测试数据进行分析后可知：低环境温度空气源冷水机组评价系统不仅使常规空气源冷水机组评价系统实现了低环境温度空气源冷水机组的低环境温度制冷工况测试,同时采用冷凝热回收技术有效地降低了评价系统的运行费用和能源消耗,而且整个评价系统工况控制稳定、设备运行可靠。较高的调节精度,有效地保证测试时数据的稳定和准确,完全可以为低环境温度空气源冷水机组的研发提供依据。     

大温差离心机组低负荷运行防喘振策略分析

稳态强磁场实验装置水蓄冷系统是国内外具有代表性的大流量大温差水蓄冷系统之一. 系统包含两个3000 m3 的蓄水罐, 为提升蓄冷量双罐均采用了自然分层技术. 由于该技术的特性, 在蓄冷后期, 离心式冷水机组的入口水温会偏低, 这导致系统新增的12 ℃ 大温差机组在试运行阶段多发低负荷喘振故障, 影响了制冷运行的稳定度. 本文首先对离心式冷水机组的喘振机理进行了阐述, 进而分析了在改造前针对该台冷水机组所做的防喘振优化措施; 通过热气旁通改造结合相关参数的合理设置, 避免机组喘振风险; 通过优化 DDC 控制, 优化机组减载能力, 避免了低负荷振动及噪声. 本次改造为系统的安全稳定运行提供了保障.     

中温冷水机组诱导系统分析

中温冷水机组诱导系统由三部分组成:中温冷水机组、集约型空气处理机组、末端诱导室。集约型空气处理机组采用椭圆管换热技术实现13℃低温送风的同时,将供回水温度提高至10/20℃。对该系统及一次回风系统进行分析,对比结果发现,处理相同房间空气时,中温冷水机组诱导系统的输入比一次回风系统输入少178.28k W,可节能42.29%;中温冷水机组诱导系统的损失比一次回风系统的损失低,两系统对应效率分别为9.49%和5.58%。     

基于有机朗肯循环的船用柴油机余热回收系统研究

本文针对某船用柴油机,利用有机朗肯循环技术,设计系统回收废气余热和主机冷却水余热,两套余热回收系统的热效率分别为21.1%和5.3%,总净功率为102.2 kW,可将柴油机的输出功率提升10.3%。在两套独立系统的基础上,进行优化并提出了主机冷却水预热、废气蒸发的方案,探讨了预热温度对系统性能的影响。优化后的系统,净功率为100.8kW。优化方案的净功率略有降低,但大大简化了系统、降低了投入成本和占用空间。     

20MW水冷磁体冷却水系统节能优化设计

针对水冷磁体运行产生的热负荷设计了本水冷系统,该系统在保障磁体稳定运行的前提下,进行了节能优化设计。其中自然分层水蓄冷技术的应用不仅节约占地还可增大蓄水量,而利用峰谷电价差进行夜间蓄冷的方式更可节约运行成本;利用闭式冷却塔在气温较低时取代上游冷水机组的设计也最大程度地节约了电能;此外在运行模式方面,系统可根据不同水冷磁体实验负荷进行灵活转换;在设备选择方面,均采用节能环保的产品,如制冷系数高的冷水机组,传热系数较高的板式换热器等。本系统对MW级以上水冷系统设计具有较好的参考价值。     

空气预冷机制冷系统故障分析及对策研究

空气预冷机制冷系统发生故障,会影响设备的正常运行.介绍了冷却水冷量不足、制冷系统无泄漏但冷媒低压过低、制冷系统泄漏三种典型故障.通过增加冷却水水量、降低水温、疏通清洗换热器改善换热效率的方法解决冷量不足的故障;减少进水量、提高进水温度解决制冷系统无泄漏但冷媒低压过低的故障;检查泄漏点并对其进行焊接或修复处理,然后进行充...     

稳态强磁场实验装置水冷系统制冷节能设计

为了缓解稳态强磁场实验装置20MW级水冷系统制冷能耗高的问题,提出了采用闭式冷却塔联合离心式冷水机组,在秋冬季节制冷使用的方案.本文详细介绍了闭式冷却塔参与制冷的运行模式、选型依据及控制逻辑.结合合肥气象数据,给出了该设备理论可使用天数,并以离心式冷水机组为参照,提出了该闭式冷却塔的节能效益模型.此外,结合系统特征,详细分析了闭式冷却塔盘管防冻策略.本文的相关结论可为夏热冬冷地区的类似水冷系统设计提供参考.     

Guided-Wave Two-Dimensional Acousto-Optic Scanner Using Proton-Exchanged Lithium Niobate Waveguide

Two-dimensional scanning of a 0.6328 mum guided-light beam has been realized using noncolinear acousto-optic (AO) coplanar Bragg diffraction together with colinear AO guided-mode to substrate radiation-mode conversion in a Z-cut Xpropagation LiNbO3 proton-exchanged (PE) waveguide. The two surface acoustic (SAW) waves utilized are at the center frequencies of 500 and 200 MHz, propagating in the Y and X axes, respectively. Two-dimensional scanning of approximately 720 resolvable light beam spots, namely, 18 40 (horizontal vertical) scanning, has been demonstrated using a light beam of 1.0 mm aperture. The total number of resolvable beam spots can be greatly increased from 720 by simply utilizing SAW transducers of larger bandwidth and a light beam of greater aperture. It should also be possible to significantly increase the diffraction efficiency from 3 % by optimizing the parameters of the PE waveguide and the SAWs.     

Effect ofγ-radiation on the spectral luminescence characteristics of impure cadmium tungstate crystals

Results of a study of the effect of γ-radiation on the spectral luminescence properties of cadmium tungstate crystals doped with silver, bismuth, and molybdenum cations are presented. Spectral characteristics of the nondnnnoped crystals are briefly described. Absorption and photo and X-ray luminescence spectra of the crystals taken before and after exposure to γ-radiation (5.5·10⁴ Gy) are compared. It is found that the spectral characteristics of the crystals doped with silver, bismuth, and molybdenum cations do not change markedly after the exposure. The relation between the type of impurity-induced defects, individual characteristics of the impurity cations, and the character of the effect of γ-radiation on the spectral luminescence properties of impure crystals is analyzed (preliminarily). Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 64, No. 1, pp. 55–60, January–February, 1997.     

Femtosecond Transform-Limited Pulse Generation by Compensating for the Linear Chirp of SPM Spectra in Dispersion Shifted Fibers

A simple technique of pulse compression, based on the linear chirp compensation of self-phase modulation (SPM) spectra in dispersion shifted fibers, is demonstrated. The optimization procedure is carried out, for a short span of a single-mode fiber, using a parabolic law, which describes the behavior of the squared output pulse width versus the pump peak power in the case of Gaussian pulses. The experimental results give a minimum pulse duration of 233 fs, which is in good agreement with the model. Shorter and coherent pulses, down to 90 fs, have been obtained by inserting an interference filter at the optical output.     

Sorting of bending magnets for the SSRF booster

The Shanghai Synchrotron Radiation Facility(SSRF)booster ring,a full energy injector for the storage ring,is deigned to accelerate the electron beam energy from 150MeV to 3.5GeV that demands high extraction efficiency at the extraction energy with low beam loss rate when electrons are ramping.Closed orbit distortion(COD)caused by bending magnet field uniformity errors which affects the machine performance harmfully could be effectively reduced by bending magnet location sorting.Considering the affections of random errors in measurement,both ideal sorting and realistic sorting are studied based on measured bending magnet field uniformity errors and one reasonable combination of bending magnets which can reduce the horizontal COD by a factor of 5is given as the final installation sequence of the booster bending magnets in this paper.     

Measurement of nonlinear coefficient of optical fiber based on small chirped soliton transmission

We measure the waveform and phase curves of short optical pulses before and after transmission over different lengths of fibers by use of the pulse analyzer with the frequency-resolved optical gating (FROG),and numerically simulate pulse evolution under the experimental conditions.The nonlinear coefficient of the fiber is given by comparing the experimental results with the numerical ones.Difference between the experiment and numerical simulation is analyzed.     

Resonance scattering of canonical elastic shells in absorbing fluid medium

Resonance scattering of elastic spherical shell and cylindrical shell while the surrounding fluid medium has absorption is studied. The normal mode solution derived using exact elastic theory and the separation of variables is still applicable. However, the scattering form function has to be modified for the absorbing medium, otherwise the unreasonable result would be obtained. The backscattering form function in the absorbing medium is redefined, and the form function of elastic spherical and cylindrical shell with vacuum or solid matter filled is calculated in various absorption conditions. The results show that the absorption of surrounding fluid leads to notable attenuation of the coincidence resonances in the mid-frequency, but it has a little influence on the low-frequency resonance scattering induced by the filler inside the shell.     

Single-beam self-referenced phase-sensitive surface plasmon resonance sensor with high detection resolution

A versatile and low-cost single-beam self-referenced phase-sensitive surface plasmon resonance(SPR)sensing system with ultra-high resolution performance is presented.The system exhibits a root-mean-square phase fluctuation of ±0.0028.over a period of 45 min.i.e.a resolution of±5.2×10-9 refractive index units.The enhanced performance has been achieved through the incorporation of three design elements:a true single-beam configuration enabling complete self-referencing so that only the phase change associated with SPR gets detected,a differential measurement scheme to eliminate spurious signals not related to the sensor response,and the elimination of retardation drifts by incorporating temperature stabilization in the liquid crystal phase modulato .Our design should bring the detection sensitivity of non-labeling SPR biosensing closer to that achievable by conventional fluorescence-based techniques.     

Influences of SiO2 protective layers and annealing on the laser-induced damage threshold of Ta2O5 films

Ta2O5 films are prepared on BK7 substrates with conventional electron beam evaporation deposition.The effects of SiO2 protective layers and annealing on the laser-induced damage threshold (LIDT) of the films are investigated.The results show that SiO2 protective layers exert little influence on the electric field intensity(EFI)distribution,microstructure and microdefect density but increase the absorption slightly.Annealing iS effective on decreasing the microdefect density and the absorption of the films.Both SiO2 protective layers and annealing are beneficial to the damage resistance of the films and the latter is more effective to improve the LIDT.Moreover,the maximal LIDT of Ta2O5 films is achieved by the combination of SiO2 protective layers and annealing.     

A stereo matching algorithm using multi-peak candidate matches and geometric constraints

Gray cross correlation matching technique is adopted to extract candidate matches with gray cross correla- tion coefficients less than some certain range of maximal correlation coefficient called multi-peak candidate matches. Multi-peak candidates are extracted corresponding to three closest feature points at first. The corresponding multi-peak candidate matches are used to construct the model polygon. Correspondence is determined based on the local geometric relations between the three feature points and the multi-peak candidates. The disparity test and the global consistency checkout are applied to eliminate the remaining ambiguous matches that are not removed by the local geometric relational test. Experimental results show that the proposed algorithm is feasible and accurate.