共查询到17条相似文献,搜索用时 93 毫秒
1.
2.
热声发动机用加热器的设计与实验验证 总被引:4,自引:0,他引:4
热声发动机利用热声效应将热能转换为机械能,热能由核心部件加热器提供。加热器在热声发动机的能量传递和转化过程中起着举足轻重的作用。针对热声发动机的工作特点,介绍了一种采用时均流对流换热公式进行热声发动机用加热器设计的方法。基于该方法,设计了一种新型热声发动机用电加热器,并应用于自行研制的太型多功能行波热声发动机试验台。设计计算和实验结果表明,该加热器能够充分满足热声发动机的加热要求。本文对以振荡流体为特征的换热器设计具有一定参考价值。 相似文献
3.
热声发动机作为一种完全没有运动部件的能量转化和传输机械具有广阔的应用前景.为了提高热声发动机的驱动性能,本文采用变负载法对热声发动机性能的影响因素进行了实验研究.实验结果表明,负载的阻力和容抗对热声发动机的加热温度、压比和声功引出有重要影响.同时,实验中还发现了能够使热声发动机瞬时消振和起振的实验方法,将极大方便对热声发动机的开关控制. 相似文献
4.
热声发动机作为一种新型的外燃式热机,具有可靠性高、使用寿命长、环境友好等优点,在热声发电、热驱动制冷等领域具有重要应用前景。本文结合热声技术和摩擦纳米发电技术的特点,首次提出了"热声驱动摩擦纳米发电机"这一热-声-电换能新流程。理论计算了驻波热声发动机和接触分离式摩擦纳米发电机采用末端耦合结构时的换能特性,并开展了系统实验研究。实验中,热声驱动摩擦纳米发电机获得了最高10 V的开路电压输出;在外接电阻为400 MΩ时,最高输出功率为0.008μW,验证了"热声驱动摩擦纳米发电机"这一概念的可行性。 相似文献
5.
热声发动机驱动的脉管制冷机是一种完全无运动部件的低温制冷机,具有非常好的应用前景,本文介绍了本实验室在这方面取得的最新进展。首先我们对驻波热声发动机进行了改进设计,提高了其驱动压比,用氦气作为工质最大压比达到了1.15。在此基础上我们用其驱动同轴双向进气小孔型脉管制冷机,通过调整热声发动机的振荡频率,使之与脉管达到匹配,最终达到了84.3K的最低制冷温度,这也是目前用驻波热声发动机驱动脉管所达到的最低制冷温度。同时,在此实验过程中,一些抑制跳频的方法也得到了实验验证。 相似文献
6.
7.
8.
9.
陈佰满黄斯珉蒋润花肖汉敏杨晓西 《工程热物理学报》2014,(6):1064
本文根据部分无法得到供电的贫困用户的调查结果,结合用户的用电需求及当地的传统烹调习惯,研制了一款利用炉灶余热驱动的双级行波热声发电机。该发电机与以木材为燃料的炉灶结合,利用炉灶燃烧后的余热作为热声发动机的驱动热源,并使用商用低成本的扬声器作为直线电机,把声功转化为有用的电能,实现热-声电的转换过程。实验初步结果显示:该双级行波热声发电机在标准大气压和空载的情况下,实现较低的自激振荡起始温度;在外接负载的情况下,对标准大气压和加压至50 kPa时分别实现了12.6 W和22.7 W的电功输出。这一成果对解决贫困地区人民无法用电的问题具有很大的意义。 相似文献
10.
采用计算流体动力学(CFD)方法,对高频驻波热声发动机和热声斯特林发动机实验系统分别进行了二维和三维数值模拟。计算模型具有与实验系统相同的几何结构、尺寸和运行工况。对计算模型的有效性进行了研究,表明实现有限换热条件的板叠实物模型适合驻波热声发动机的模拟,而实现局域热平衡的多孔介质模型适合热声斯特林发动机的模拟。计算结果成功观测到了非线性的自激振荡演化过程,捕捉到了两种发动机的不同非线性现象。计算结果分别给出了两种热声发动机内部的声场分布特性和复杂流场。计算结果与实验结果的对比验证了CFD方法对高频驻波热声发动机和热声斯特林发动机模拟的有效性。 相似文献
11.
12.
Chandrachur Bhattacharya Sudeepta Mondal Achintya Mukhopadhyay 《Combustion Theory and Modelling》2020,24(3):530-548
The topic of thermoacoustic instabilities in combustors is well-investigated, as it is important in the field of combustion, primarily in gas-turbine engines. In recent years, much attention has been focused on monitoring, diagnosis, prognosis, and control of high-amplitude pressure oscillations in confined combustion chambers. The Rijke tube is one of the most simple, yet very commonly used, laboratory apparatuses for emulation of thermoacoustic instabilities, which is also capable of capturing the physics of the thermally driven acoustics. A Rijke tube apparatus can be constructed with an electrical heater acting as the heat source, thus making it more flexible to operate and safer to handle than a fuel-burning Rijke tube or a fuel-fired combustor. Augmentation of the heat source of the Rijke tube with a secondary heater at a downstream location facilitates better control of thermoacoustic instabilities. Along this line, much work has been reported on the investigation of thermoacoustics by using computational fluid dynamics (CFD) modelling as well as reduced-order modelling for both single-heater and two-heater Rijke tube systems. However, since reduced-order models are often designed and built upon certain empirical relations, they may not account for the dynamic behaviour of the heater itself, which is a critical factor in the analysis and synthesis of real-time robust control systems. This issue is addressed in the current paper, where modifications have been made to existing models by incorporating heater dynamics. The model results are systematically validated with experimental data, generated from an in-house (electrically heated) Rijke tube apparatus. 相似文献
13.
In an open cycle traveling wave thermoacoustic engine, the hot heat exchanger is replaced by a steady flow of hot gas into the regenerator to provide the thermal energy input to the engine. The steady-state operation of such a device requires that a potentially large mean temperature difference exist between the incoming gas and the solid material at the regenerator's hot side, due in part to isentropic gas oscillations in the open space adjacent to the regenerator. The magnitude of this temperature difference will have a significant effect on the efficiencies of these open cycle devices. To help assess the feasibility of such thermoacoustic engines, a numerical model is developed that predicts the dependence of the mean temperature difference upon the important design and operating parameters of the open cycle thermoacoustic engine, including the acoustic pressure, mean mass flow rate, acoustic phase angles, and conductive heat loss. Using this model, it is also shown that the temperature difference at the regenerator interface is approximately proportional to the sum of the acoustic power output and the conductive heat loss at this location. 相似文献
14.
15.
16.