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131.
针对室外热环境评价指标湿球黑球温度在实测和数值计算中都比较难获得的问题,在湿热地区广州夏季收集了空气干球温度、湿球温度、黑球温度、相对湿度、风速、太阳辐射和湿球黑球温度等数据,对收集的数据进行相关性分析和回归分析,相关性分析结果表明:空气温度、相对湿度、太阳辐射与湿球黑球温度具有一定的线性相关度,可以采用上述三个气象因子作为湿球黑球温度的简化计算参数;回归分析结果表明:回归的关联式与实测湿球黑球温度的相关性较高,并且满足多元线性回归的各项检验,认为该回归方程具有较高的可信度,可以在城市热环境的实测评价和数值预测过程中,作为湿球黑球温度的简化计算方法应用。 相似文献
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KUBOAT Takashi 《机械工程学报(英文版)》2012,25(5):919-925
With the increasing demand for the clean sustainable power, the turbine design urgently turns to increase the capability significantly toward higher head for generating larger power. Currently, there are many studies in the field of the bulb turbine with single-stage runner, though reports about counter-rotating tandem-runner are rare. However, the further high-head application with the single-stage runner is very difficult to achieve due to the limit of the specific speed. In this paper, a new bulb turbine with the tandem-runner is designed in order to substantially increase the applicable limit toward higher head with larger power. A half of the net head is absorbed by the frontal runner which can generate output power, while the remaining half is absorbed by the rear runner. To generate the Euler energy required for the rear runner, the frontal runner has the counter-rotation against the rear runner so that the counter-rotating tandem-runner can meet the purpose of double head and power under the same size as the conventional bulb turbine. Supply and demand of Euler energy between the two runners are thoroughly optimized through the detailed flow analysis, in order to secure the stable operation. As a result, the interference of Euler energies between the outflow from the frontal runner and the inflow to the rear runner is confirmed to be very small on the counter-rotating interface between the two runners. The prediction method of on-cam performance between the two adjustable runners is also developed numerically, which provides optimal flow between the two runners. This research provides a theoretical basis for the optimal design and operation of the counter-rotating tandem-runner bulb turbines. 相似文献
135.
The starches separated from bulbs of four different lily cultivars (Lanzhou, Pinglu, Yixing‐1, and Yixing‐2) were investigated for physicochemical, morphological, crystalline, and thermal properties. AM content of lily bulbs starches from different cultivars ranged from 19.46 to 25.17%. The swelling power of starches ranged between 14.4 and 21.3 g/g, and the solubility ranged from 8.92 and 16.6% at the temperature of 85°C. Four cultivars of lily starches paste had excellent transparency and the transmittance value of Lanzhou lily as high as 54.7%. The transmittance of the gelatinized aqueous starch suspensions, from all lily cultivars, decreased with increase in storage period. The shape of starch granules varied from triangular to cylindrical and XRD of four lily starches all showed B‐type pattern. The transition temperatures and enthalpy of gelatinization (ΔHgel) were determined using DSC. Tp varied from 62.52 to 65.25°C. Pinglu lily starch showed the highest ΔHgel and gelatinization range (Tc–To) index among starches from four different lily cultivars. 相似文献
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根据干湿球法测量相对湿度的原理,分析了干球温度、湿球温度、风速对相对湿度测量误差影响,对相对湿度测量合理选择测试仪表有一定的指导意义。 相似文献
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本文从总体方案与工艺流程、传动部件与造型机械手以及微机气动控制系统等方面介绍了一种经济型的立体花色冰淇淋成型机的设计。 相似文献
140.
介绍了碱回收燃烧工段的工艺流程、测控系统、可编程逻辑控制(PLC)系统结构及硬件设计,同时,详细阐述了实现上汽包自动上水所采用的连锁报警及虚假水位判断措施、单冲量控制方式. 相似文献