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联合循环、STIG循环、HAT循环及其相关循环的热力性能比较 总被引:3,自引:0,他引:3
1引言本文分析并比较了燃气一蒸汽联合循环(CC)(图川山、注蒸汽燃气轮机(STIG)循环z图2)l’]、湿空气透平(HAT)循环(图3)[’1及采用中冷或再热手段后相应循环的性能.为了不使系统过于复杂,只采用一级中冷、一级再热,中冷器和再燃室的位置与通常的设计相同。中冷器所用冷却水来自环境,吸收热量后又回到环境。选用余热锅炉型CC,HAT循环选用文献[3]提供的结构。2计算结果及分析计算条件:(a)环境温度20”C,压力0.101325MPa,湿度sg/bgDA;(b)压气机绝热效率0.88,燃气透平相对内效率0.9,蒸汽透平相对内效… 相似文献
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《工程热物理学报》2016,(2)
为了深入研究逆布雷顿空气制冷机的降温特性与制冷性能,论文首先采用CFX数值模拟方法,对透平膨胀机冷端通流部分的流动与热力学过程进行了数值模拟,进一步对整机的热力性能进行了分析;在此基础上探讨了制动功率对膨胀机降温特性影响;并改进了逆布雷顿空气制冷机综合实验台,采用风机回路闭式循环,进行了定制动压力和定特性比两种典型制动策略下制冷机降温性能的实验研究。结果表明:通过调节风机闭式循环制动压力来匹配膨胀机工况的变化方案可行,理论预测与实验结果吻合较好;透平膨胀机的绝热效率62%,在120 min内制冷机最低无负荷出口温度达到了-170℃;采用透平膨胀机的逆布雷顿空气制冷机具有优异的制冷性能。 相似文献
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改进型氢氧联合循环及其性能初步分析 总被引:1,自引:0,他引:1
1前言氢能既具备矿石燃料的优点,又符合长远能源发展的要求,被称为21世纪的能源。氢能发电是氢能利用的一个重要方面,近年来出现了各种氢能发电方案。文献山提出了氢氧联合循环(包括混合式和面式);此外还有高温蒸汽朗肯循环,氢氧燃烧,加热氦(或二氧化碳)的闭式透平K’];对燃用液氢的系统也有论述*’]。本文在已有工作的基础上,综合了混合式和面式氢氧联合循环的一些特点,提出了氢氧联合循环的改进型式。本文将着重讨论这种改进循环的性能,并与混合式多级再热氢氧联合循环加以比较,对氢氧联合循环的进一步发展作一初步尝… 相似文献
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部分空气湿化燃气轮机循环设计工况性能分析 总被引:1,自引:0,他引:1
在参数优化的基础上,对加湿空气和未加湿空气混流位置不同的两种PEvGT循环设计工况性能进行研究,并与HAT和STIG循环进行了对比。研究表明:混流位置对其热力性能有重要影响;未加湿空气、加湿空气及蒸汽在回热器前混合(PEvGT-2)循环,最佳压比与HAT循环最佳压比接近(10左右);在各自的效率最高点,四种循环中PEvGT-2效率最高,未加湿空气、加湿空气及蒸汽在燃烧室前混合(PEvGT-1)循环比功最大;纯发电时,两种PEvGT的效率最高点对应的分流比在0%~20%之间,且通过对换热器面积和湿化器高度的比较和分析也表明分流比选取在该范围内比较经济;四种循环的效率、比功和最佳压比随透平初温的升高而上升,分流比对PEvGT-2循环的效率、比功和最佳压比影响较小,但对PEvGT-1循环影响较明显。 相似文献
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核能湿氦气透平闭式循环探索研究 总被引:2,自引:1,他引:1
1前言前苏联于1954年建成世界首座核电站后,核能和平利用得到蓬勃发展。高温气冷堆(HTGR)受到重视,进展很大山,许多学者也在积极开展相应的能量转换系统的研究,最据代表性的是模块化高温气冷堆一氦气轮机闭式循环(MHR--GT)[‘-‘]。从能的梯级利用原理看,它在热力学上是不完善的,仍有较大提高性能的空间。本文基于总能系统概念l’],在核能Brayton闭式循环(NEBCC)l’]基础上,应用工质湿化循环原理l’,‘],探索一种新颖的核能湿氦气透平闭式循环(HHTCC)。它更能充分发挥高温堆的高温优势,是一种较理想的核… 相似文献
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随着航空技术的发展,大量机载设备特别是航空仪器仪表与传动系统采用电能驱动,航空电源在现代飞行器中的作用愈发重要。作为飞机发电机与机载用电设备之间的电力枢纽,飞机二次电源的可靠性对于维持用电设备的稳定运行具有重要的意义。应用BIT技术可以实现对飞机二次电源运行状态的实时监控,然而虚警问题对BIT技术的应用造成了很大的困扰。针对某型飞机二次电源采用合理的硬件设计结合有效的检测算法可以显著改善BIT系统的虚警率,这就使操作人员能够准确掌握飞机二次电源的工作状态,及时的发现问题、减少损失。 相似文献
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Marine propulsion unit (MPU) is one of the dominant vibration and noise sources onboard ship. Its vibration can be attenuated effectively by isolating MPU with low-frequency mounting system. But this is difficult to implement due to the stringent requirement of MPU alignment with the propulsion shafting. In this paper a novel air spring mounting system (ASMS) for propulsion system is proposed consisting of air spring subsystem, alignment control subsystem and safety protection subsystem. The load distribution optimization method and dynamic model of ASMS are presented. The factors that affect system stability and natural frequencies are analyzed, as well as the design measures to enhance system performance. A theoretical model is presented to estimate the isolation effect of ASMS. The monitoring model of alignment between MPU and propulsion shafting is established, followed by the alignment control algorithm and converge rule which assures the fast and uniform convergence of both air springs? load distribution and alignment control process. Safety protection mechanism is designed to ensure that the MPU can operate safely in case of ASMS failure or other extreme circumstances. A scaled ASMS prototype is manufactured and tested on a special experimental setup. Experimental results validate the effectiveness of theoretical models and show that the performance of ASMS satisfies the operation requirements of MPU. 相似文献
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近年来,航空安全问题引人关注。传统航空应急指挥系统模型建立存在线性信号分析失常、应急指挥模型时效性滞后、空中管制系统信号算法穿透力差等问题,无法满足现代航空安全应急指挥的要求。针对传统航空应急指挥系统存在的问题,提出基于卡尔曼滤波和AHP的航空管制航空器应急指挥系统设计。利用卡尔曼滤波良好的线性分析能力与抗干扰性,结合AHP航空数据分析式,设计出针对性强的航空管制航空器应急指挥系统,并对设计系统进行指挥应用模型的效能评估。评估数据表明,提出的基于卡尔曼滤波和AHP的航空管制航空器应急指挥系统设计满足航空管制应急的使用要求。 相似文献
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K. H. Kim H. -J. Ko K. Kim Y. -S. Jung S. -H. Oh K. -J. Cho 《Journal of Engineering Thermophysics》2012,21(1):1-15
The transient thermal behavior in the cryogenic oxidizer tank for the liquid propulsion system of the KSLV-I satellite launching
space vehicle is theoretically investigated for the pressurization process by gaseous helium injection followed by the readiness
check stage. The numerical model is established using the transient mass and energy conservation of oxygen/helium mixtures
both in ullage and liquid regions. At the liquid-gas interface, various modes of heat and mass transfer are considered, including
the liquid evaporation and the helium absorption. The present study focuses on the effects of the increasing pressurization
level on some of important properties that should be considered in the propulsion system design, such as tank pressure, ullage
gas temperature, and evaporation of liquid oxygen. Particularly, the tank pressure drop after the pressurization is investigated
in the proposed design of propulsion system. Also, the effect of the initial loading of liquid oxygen in the oxidizer tank
is studied and discussed. As for the helium absorption into the liquid region, its mass is negligibly small and it should
not be the concern in design and operation of the oxidizer tank system. 相似文献
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Yutian Wang Longjiang Zheng Peiguo Hou Chunhai Hu 《Optics and Lasers in Engineering》2005,43(10):1145-1150
In this paper an electro-optic current transformer (CT) is designed which is used for measuring the super-high-voltage station's line current. The measurement system utilizes a conventional CT as the sensing probe whose electronics is optically powered. The paper describes the principle of measurement system, including the system design, optically powered sensing probe, the data link measurement signal processing and results showing current measurement by means of CT. 相似文献
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A compact, photocouplerlike system is presented for wireless transcutaneous transmission of biological signals. The system consists of an optically powered near-infrared light transmitter, a receiver for the signals from it, and a near-infrared light source with which to irradiate it. The transmitter, which is implanted under the skin, is transcutaneously coupled with the receiver and the light source, which are combined and placed on the skin. The transmitter, which is powered transcutaneously by the light source, then amplifies a signal input to it and sends intensity-modulated light transcutaneously to the receiver. With this system, electromyograms and neuronal firing patterns of live rats have been successfully recorded. 相似文献