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为降低翅翼型纵向涡发生器与螺旋片复合强化的套管式换热器壳侧传热阻力,提出一种新型翅翼型纵向涡发生器,即流线型涡发生器。采用实验和数值模拟方法研究了流线型涡发生器与螺旋片复合强化的换热器壳侧的传热和阻力特性并与三角翼型涡发生器(DWP)的强化效果进行比较,考察了流线型涡发生器common-flow-down(CFD)和common-flow-up(CFU)两种安装方式的强化效果,分析了流线型涡发生器的减阻机理。结果表明,在涡发生器面积和迎流角相同的情况下,流线型涡发生器可以取得与三角翼型涡发生器相同(Re<8000)或略低(Re>8000)的传热系数,但其产生的流动阻力比三角翼型涡发生器低21%;在相同压降条件下,common-flow-up安装方式的综合传热效果优于common-flow-down;流线型涡发生器减阻机理在于提高了速度场与压力场的协同性。 相似文献
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《化工学报》2017,(4)
为降低翅翼型纵向涡发生器与螺旋片复合强化的套管式换热器壳侧传热阻力,提出一种新型翅翼型纵向涡发生器,即流线型涡发生器。采用实验和数值模拟方法研究了流线型涡发生器与螺旋片复合强化的换热器壳侧的传热和阻力特性并与三角翼型涡发生器(DWP)的强化效果进行比较,考察了流线型涡发生器common-flow-down(CFD)和common-flow-up(CFU)两种安装方式的强化效果,分析了流线型涡发生器的减阻机理。结果表明,在涡发生器面积和迎流角相同的情况下,流线型涡发生器可以取得与三角翼型涡发生器相同(Re8000)或略低(Re8000)的传热系数,但其产生的流动阻力比三角翼型涡发生器低21%;在相同压降条件下,common-flow-up安装方式的综合传热效果优于common-flow-down;流线型涡发生器减阻机理在于提高了速度场与压力场的协同性。 相似文献
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《化工进展》2017,(6)
涡流发生器是一种广泛应用的被动强化传热元件,在换热器的换热壁面上以阵列形式布置。涡流发生器靠诱导和产生涡旋来削减或破坏壁面边界层从而达到强化换热。本文对安装腰槽开孔矩形翼涡流发生器和未冲孔矩形翼涡流发生器以及圆孔矩形翼涡流发生器的矩形通道进行了传热和流阻特性的实验研究。实验雷诺数范围为Re=1000~4000。结果表明:在相同雷诺数下,安装有腰槽开孔矩形翼涡流发生器的矩形通道的换热效果和流阻特性优于未冲孔矩形翼涡流发生器和圆孔矩形翼涡流发生器,腰槽开孔矩形翼涡流发生器综合换热性能最好。涡流发生器布置攻角和纵向间距对腰槽开孔矩形翼涡流发生器传热和流阻有较大影响,对比不同涡流发生器布置攻角和纵向间距,得出90°攻角布置和纵向间距为80mm布置的腰槽开孔矩形翼涡流发生器总和换热性能最好。 相似文献
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In this work, a strategy is presented to optimize the ozone generation by response surface methodology. A dielectric barrier discharge ozone generator was developed in which it is possible to control electrical current frequency and gas flow entering the generator. Response surface methodology was used to identify ozone generator optimum operational conditions, that is, those that permit considerable ozone productivity and high concentration of ozone gas. 相似文献
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An ozone generator using a rotating electrode to improve ozone generation efficiency is proposed. The ozone generator electrode unit consists of a rotating electrode and fixed electrode. The rotating electrode has the grounded 36 pieces of tungsten wires fixed in parallel to the rotation axis on the rotating cylinder surface. A dielectric electrode is used as a fixed electrode located on the inside of the tube of the electrode unit. The width of the apparent discharge gap is 1mm. Alternating current with a frequency of 50 Hz is applied to the electrode unit. The rotation speed can be adjusted from 0 rpm to 1200 rpm by a variable speed motor. Oxygen gas is used as the material gas. Higher ozone concentration and higher ozone generation efficiency are obtained compared with that when the rotation speed is 0 rpm. The gas temperature is measured at the inlet and outlet of the ozone generator, and the rotation speed for the cooling effect is most effective at about 500 rpm. The maximum generation efficiency is estimated to be 61 g/kWh at 800 rpm, and this value is twice as large as in the case of 0 rpm. 相似文献
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为满足1.5万t/aPVC的生产需要,对乙炔发生器进行了技术改造。改造内容包括发生器本体的结构改造,电石贮斗的改造,气液分离器的改造等。经过改造,降低了发生器的压力,减少了生电石,提高了生产能力,杜绝了泄漏现象,改善了操作环境。 相似文献
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The generation of gaseous singlet oxygen by gas‐liquid reaction of chlorine with alkaline solution of hydrogen peroxide in spray form was studied experimentally on the originally designed device with a fast separation of reacted liquid from gas. The singlet oxygen yield, residual chlorine, and water vapor content in gas were measured under different experimental conditions of the centrifugal spray singlet oxygen generator (CSSOG) using nitrogen as a dilution gas. A characteristic feature of the CSSOG is a high utilization of the chemicals and production of singlet oxygen at a very high total pressure even near the atmospheric pressure. This generator developed originally for driving a chemical oxygen‐iodine laser (COIL) could be employed also as an efficient singlet oxygen source in material science, chemical synthesis, and others. 相似文献
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介绍废热发电在硫酸装置中的重要作用与价值,论述硫酸装置废热发电自保运行的可行性。对于发电容量大于用电负荷的装置,当外电网断电时,废热发电机组可起到相对“独立”电源的作用,维持硫酸装置的正常生产;对于发电容量略小于用电负荷的装置,当外电网断电时,可通过调整工艺负荷实现装置的自保运行。由于废热发电系统的不稳定性和相对不可调节性,废热发电自保运行不应作为硫酸装置的主要供电方式,只有在电力供应相对紧张的地区才可适当采用。论述了硫酸废热发电自保运行在设计中需注意的几个问题。 相似文献
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对脉冲萃取柱的空气脉冲旋转阀产生的空气脉冲发生过程进行了分析,给出了其充气和排气过程特征,得到脉冲腿内液面在空气脉冲作用下随时间变化的理论模型,并将理论计算结果与大型空气脉冲旋转阀产生的脉冲压力变化及在其作用下在直径0.3 m、高5.6 m无筛板脉冲柱中产生的液体运动的实验结果进行了对比. 结果表明,空气脉冲旋转阀充放气时间很短,充气时间约0.2 s,放气时间不超过0.05 s,加压空气通过旋转阀后产生接近梯形波的空气脉冲压力,脉冲柱内液面随时间变化曲线为类似正弦形,理论模型计算与实验结果符合很好,验证了模型的可靠性. 相似文献
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平煤集团朝川矿以焦炉气为燃料,对采用燃煤气锅炉—蒸汽轮机发电、柴油机(改)发电机组、燃气轮机热电联合循环发电三种方案分别进行了比较研究,确定选用经济效益最好、污染小的燃气轮机热电联合循环发电方案。 相似文献