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1.
防虫网对节能日光温室通风性能影响的研究 总被引:1,自引:3,他引:1
自然通风是决定日光节能温室质能平衡和调节微生态环境平衡的重要因素。为了提高节能日光温室的环境管理和结构设计水平,有必要研究防虫网对日光温室通风性能的影响,以提高日光温室的绿色产品生产率。因此,运用气体衰减示踪技术和数理统计理论,研究了日光温室不同形式通风机构的通风性能。试验研究表明在通风口处装设防虫网会显著地减少日光温室的通风率,有时可高达50%。研究还表明,无论装设有无防虫网,卷膜通风机构比拉膜(推膜)通风机构都具有较大的通风率,有时前者是后者的1.4倍左右。 相似文献
2.
深入分析研究了农业环境控制用轴流通风机的性能和结构特点。实验分析了墙装式高效通风机进口流速场,并建立了通风机入口轴向流速分布模型。对传统的通风机设计方法进行分析研究后,提出高效的农业环境墙装式轴流通风机的设计方法,并用该方法计算了实例,取得了满意的结果。 相似文献
3.
肉种鸡鸡舍夏季通风降温试验 总被引:1,自引:0,他引:1
在两栋长145m,跨度5.4m的双坡式有窗封闭舍内,采用三层笼养方式分别饲养700只235日龄的艾维菌肉种鸡,将其中采用轴流式风机加湿帘纵向通风系统的一栋鸡舍作为试验组,而将另一栋采用窗户自然通风的鸡舍作为对照组,于夏季进行为期15d的试验,结果表明试验组与对照组的舍内温度在1d内明显不同,且舍外温度越高,试验组的舍内降温效果越好,相应地,试验组也减轻了肉种鸡的夏季热应激。 相似文献
4.
Three typical commercial buildings in Chongqing, P.R. China were selected to study the actual summertime operation and energy situations of heating ventilating and air conditioning (HVAC) systems in commercial buildings. Based on tests of energy consumption of HVAC systems in these three buildings, we analyzed the electricity consumption of the main components of the air conditioning systems. The energy efficiency of the chillers and air conditioning water distribution systems were studied. The indoor thermal environment in these three buildings were also tested and discussed. It is concluded that problems exist in the air conditioning systems of commercial buildings. Among the problems are over sized system design, low equipment operating efficiencies, poor operation management, and lack of indoor temperature controls. To reduce energy consumption of HVAC systems in commercial buildings, we propose energy efficient strategies such as sizing systems based on accurate load calculation and automatic control under partial load conditions. 相似文献
5.
水生诱导根系是陆生植物水培条件下良好生长的基础,以鸡冠花(celosia cristata L.)扣凤凰草(Myriophyllum aquaticum(Vell.)Verdc)为材料对花卉水生诱导根系做了初步的研究。把鸡冠花扣凤凰草水培、旱种扣旱种改水种进行了对比试验,并与水稻根系进行了比较。结果表明:水培条件下诱导的根系有较高的根活性;旱生植物在水生条件下中柱部分并没有什么大的变化,但皮层薄壁组织细胞产生裂缝,生成结构类似水稻根系的通气组织。水生诱导根系在部分淹水条件下形态结构扣生理活性都发生了相应变化。以适应水培条件下正常生长。 相似文献
6.
本文对棚窖的结构进行了分析,找出了影响经济林产品贮藏的原因,并在此基础上对普通棚窖进行了改建,可使贮期延长1个月左右,且贮藏效果较好。 相似文献
7.
新型大棚猪舍环境控制效果研究 总被引:1,自引:0,他引:1
通过对猪舍屋顶热工指标和通风量进行计算,对舍内空气环境进行测定与分析,研究了新型大棚猪舍保温隔热,通风性能及其应用效果,结果表明:该猪舍屋顶冬,夏季总热阻分别为0.824m^2k/w和0.864m^2k/w,冬,夏季通风量分别为355.8m^3/h和12153.4m^3/h,优于有窗舍,且优于或符合设计要求。舍内空气环境,温度冬,夏季分别为11.3℃和26.50℃;相对湿度冬,夏季分别为72.3%和80.2%,气流速度冬、夏分别为0.19m/s和0.72m/s;NH3浓度冬,夏季分别为0.113mg/m^3和0.656mg/m^3,CO2浓度冬,夏季分别为1964mg/m^3和1527mg/m^3,优于有窗舍,大棚舍用于育肥猪舍冬,夏季均有较好的应用效果。 相似文献
8.
为开发节能高效的柑桔贮藏保鲜库,通过设计、性能测试、贮藏试验,研制出湿冷通风库。库体总热阻为 5.07 m2·℃/W,耗能为2.27 kW·h/100 m3·h,比普通冷库减少能耗50%;温度可降至-5℃以下,自动控制精度±0.1℃;相对湿度可升到99%,自动控制精度±2%。锦橙、椪柑在湿冷通风库中贮藏的呼吸强度分别为4.29、2.34 mg/kg·h,锦橙湿冷通风贮藏150 d腐烂率为6.32%,椪柑湿冷通风贮藏120 d腐烂率为5.38%,腐烂率明显低于在改良通风库贮藏(锦橙10.67%、 相似文献
9.
Ventilating vacuum method can overcome the clogging problem which often occurs on the traditional vacuum method dewatering dredged clays with high initial water contents. However, how to analyze the anti-clogging behavior of ventilating vacuum method is an important issue in practical engineering. A radial drainage model was established based on the filtration theory developed by Ruth. The vanity of the model was verified using the test results of ventilating vacuum, and the change law in average radical dewatering resistance of dewatering layer which reflects the filtration performance was investigated during the dewatering process. It is indicated that the dewatered layer is compacted by traditional vacuum method during the dewatering process. Its corresponding pore structure is unstable, thus the drainage pipeline often clogs. While the technique of ventilating vacuum provides a powerful way to overcome the clogging problem, and the pore structure is stable during the dewatering process. 相似文献
10.
浅圆仓环壁通风降温系统的性能试验与风道设置优化 总被引:1,自引:1,他引:0
通风降温是实现粮食保质储藏的重要措施。以大直径浅圆仓为研究对象,建立了环壁分层通风快速降温实验系统,进行了不同工况的降温实验,研究在粮食初入仓阶段的降温过程中,影响粮堆内温度、水分均匀性的因素。结果表明:外界热环境对降温速度有明显影响,过渡季高温期工况和夏季工况下,降温速度分别为0.43和0.16℃/h,纵向层间温差分别为0.5和1.6℃,降温后粮堆平均温度为17.24和22.76℃,分别达到准低温储粮(20℃)和常温储粮(25℃)的范围。采用露点以上温度进行送风,降温过程粮堆内空气相对湿度较为稳定,波动幅度在5%以内。采用计算流体力学(computer fluent dynamic,CFD)方法对环壁风道的配置进行了模拟研究,模拟结果与实验结果的平均相对误差为6.43%,证实了模拟的合理性与准确性。模拟结果表明,环壁风道上移后,增强了上部粮堆的降温效果,提高了整体降温速度,改善了粮堆温度的均匀性。 相似文献