共查询到17条相似文献,搜索用时 69 毫秒
1.
2.
3.
4.
5.
6.
7.
8.
归纳了液化天然气(LNG)工厂换热器设计和运行中常见的传热问题。分别论述了换热器传热的内部问题和外部问题的成因和防止对策。 相似文献
9.
10.
针对煤层气特点以及开发过程中压裂工艺技术存在的问题,研究了一项以套管注入、高排量、活性水携砂为主的煤层气清水压裂配套工艺技术。该技术在山西沁水盆地SH煤田现场应用实践了6口井,并获得成功,压后正处于排水阶段,出气效果明显。 相似文献
11.
云南煤层气资源分布及勘探开发前景 总被引:1,自引:0,他引:1
云南煤炭资源量达439×108t,煤层气资源约为45×1010~50×1010m3,占全国总量的1·85%,广泛分布于21个聚煤区内,其中14个煤区和7个煤田,但其分布具有很大的差异性。在分析云南煤层气资源分布特征的基础上,根据煤层气地质构造选区条件,通过优选提出恩洪盆地、老厂—圭山盆地、镇雄盆地、昭通盆地等煤层气勘探方向,并分析和展望了云南煤层气勘探开发的前景。 相似文献
12.
13.
14.
《Advanced Powder Technology》2020,31(7):2866-2879
This paper presents a novel method to predict the gas layer thickness δ′ in an improved cluster renewal model (ICRM) to calculate the heat transfer coefficient h′c for a rolling circulating fluidized bed (RCFB). Eulerian-Eulerian two-fluid model (TFM) with kinetic theory of granular flow is used to perform a numerical simulation. After comparing the pressure gradient −△p/△z′ and the simulated heat transfer coefficient between multiphase and the wall hgs with previously published experiment data, the correctness and reliability of the simulation are able to be verified. In conclusion, firstly, the variation of h′c calculated from δ′ in the ICRM is almost the same with hgs in the case that the RCFB undergoes the rolling motion. In order to quantitatively evaluate the proposed novel method, an error percentage α between h′c calculated from δ′ and hgs is 2.043% which is less than 5%. This certified that the novel method to predict δ′ in the ICRM has higher accuracy to calculate h′c. Secondly, h′c calculated from δ′ is mainly influenced by rolling amplitude Θ rather than by rolling period T. Specifically, with the increase of Θ, amplitudes of Ts are decreased, which is caused by the increased heat transfer and the decreased δ′ between cluster and wall. The decreased amplitudes of Ts are able to increase heat transfer efficiency, which eventually increases h′c. Thirdly, in the case that normalized rolling period t/T is changed from 0 to 0.5, higher h′c calculated from δ′ in Region Ⅰ results from the large local cross-sectional particle volume fraction clocal in Region Ⅰ with a smaller δ′, while lower h′c calculated from δ′ in Region III results from the smaller clocal in Region III with a larger δ′. Therefore, it is concluded that h′c calculated from δ′ is able to well predict the bed-to-wall heat transfer coefficient of the RCFB even if the rolling motion is considered. 相似文献
15.
吸附式制冷技术在空调应用中的研究进展 总被引:2,自引:1,他引:2
吸附式制冷符合环保要求,能有效利用低品位热源的特点使得近年来在空调制冷吸附热泵中的应用研究获得了不少进展,本文综述了近年来吸附式制冷技术中低品位热源采集,吸附工质对开发及吸附制冷过程模拟等方面的研究进展。 相似文献
16.
钛铝基金属间化合物是一种理想的高温结构材料,但因存在室温塑性差、加工困难等不足而限制了其发展与应用。电子束粉末床熔融(Electron Beam Powder Bed Fusion, EB?PBF)技术能够实现近净成形,其加工中的低热应力特点适宜脆性材料的制备,是近年来广受关注的新型钛铝基金属间化合物成形方法。对用电子束粉末床熔融制备的钛铝基金属间化合物进行了介绍,并对近年来发表的以EB?PBF钛铝材料为研究对象的相关文献进行了综述。从工艺、后处理和性能表征等角度对目前的研究现状进行了分析总结,并对未来的研究工作提出了展望。 相似文献
17.
介绍了直接蒸发冷却式水源热泵空调机的原理和特点;综述了直接蒸发冷却式水源热泵空调机用纸质、金属质、泡沫陶瓷质和其它材质热湿交换材料及其应用的最新研究进展;预测泡沫陶瓷将是空调机热湿交换材料的主要发展方向。 相似文献