江南地区传统建筑被动降温策略研究

本文从江南地区传统建筑调研结果中提取有效的被动降温措施，结合建筑气候数据分析辅助软件，总结和研究针对该气候条件下有效实用的设计策略，为今后江南地区的建筑被动降温设计提供理论指导。     

封闭式气膜煤棚瓦斯运移规律与通风控制研究

针对平舒煤矿新建封闭式气膜煤棚内部瓦斯安全与通风控制问题,通过构建气膜内部流场CFD模型仿真得出瓦斯和气流在气膜煤棚内的分布和运移规律,进而优化设计气膜瓦斯传感器监测点和通风控制系统,提出封闭式气膜煤棚通风多变量模糊控制技术,该通风技术可有效控制气膜煤棚内瓦斯和压力。     

水电站地上式主变压器室散热分析及处理措施

水电站主变压器在运行过程中,如果不能及时散热,一旦环境温度超过了工作温度,则将对其工作性能产生影响。因此,为了保证主变压器能够安全稳定地运行,根据水电站地上式主变压器室的布置特点,经综合分析考虑,选取了3种夏季通风计算温度和3种容量的主变压器,对其自然通风散热情况进行计算,从而得到了在各种工况下自然通风洞的尺寸,以为水电站地上式主变压器室的通风方案设计提供参考。     

人防工程通风设计中的一些问题

针对人防工程通风设计中容易发生的一些问题进行了探讨,阐述了过滤吸收器、油网过滤器、通风密闭阀门的选择方法,指出人防工程平战功能转换措施和系统的战时控制方法设计必须齐备详实。     

Impact of passive cooling techniques on energy demand for residential buildings in a Mediterranean climate

This study presents the thermal analysis of a building prototype, which was designed and built in accordance with energy efficiency measures to improve indoor thermal comfort, particularly in summer. The building prototype is located in Souidania (20 km southwest of Algiers, latitude 36°7N, Longitude 03°2E). The location is characterized by a temperate Mediterranean climate. In order to perform this analysis, various activities are carried out: a series of monitoring campaigns; dynamic simulations with TRNSYS software, calibration of the model with experimental data and comparative study with buildings that use different wall constructions. Based on a validated building thermal model, dynamic analysis is carried out in order to evaluate the impact of thermal mass and of eaves and night ventilation. The results demonstrate that cooling energy demand is more affected by thermal transmittance values than by the envelope thermal mass. A recommended guideline for the optimum overhang length for south-facing windows is proposed. Ultimately, it is found that the combination of both natural ventilation and horizontal shading devices improves thermal comfort for occupants and significantly reduces cooling energy demand.     

九顶山铜钼矿井下通风系统阻力测定结果分析与对策措施

以九顶山铜钼矿为例,系统介绍矿井通风阻力的测定方法、测点布置及测定路线选择,依据测定结果对矿井通风系统进行合理性分析,并提出降低矿井通风阻力的对策措施。为降低通风电耗、减少通风费用、减少风压损失和保证矿井安全生产提供科学的理论依据。     

复杂地质真空预压压力过低原因探讨

本文结合平潭某建筑场地真空预压地基处理密封膜下真空压力不足的工程实例,通过分析真空压力过低的原因,供有关工程参考。     

Uniformity of stratum‐ventilated thermal environment and thermal sensation

Three human test series were conducted to evaluate the uniformity of the thermal environments in a stratum‐ventilated chamber with dimensions of 8.8 m (L) × 5.1 m (W) × 2.4 m (H). In all, nineteen conditions were generated by adjusting the room temperature, supply airflow rate, and supply terminal type. An air diffuser performance index (ADPI) of at least 80% was achieved for most cases. This result shows that the air velocity and temperature in the occupied zone are reasonably uniform. Subjective assessments using the ASHRAE 7‐point scale indicate that the thermal sensations of the subjects in stratum ventilation are also uniform. This study examines the applicability of the predicted mean vote (PMV) model for evaluating stratum ventilation. When compared to the actual mean thermal sensation votes (ATS), the PMV values are acceptable. The PMV results at a height of 1.1 m above the floor show better agreement with the ATS than at a height of 0.1 m.     

Comparative analysis on temperature characteristics of hydrogen-powered and traditional fossil-fueled vehicle fires in the tunnel under longitudinal ventilations

Vehicle fires in the tunnel are a great threat to the safe operation of the tunnel. Due to the rapid development of the hydrogen economy, the fire due to the hydrogen leakage could not be avoided and may bring great damage to the passengers and infrastructure. Due to the large difference between pool fires of traditional fossil-fueled and jet fires of hydrogen-powered vehicles, it is in doubt whether the existing longitudinal ventilation design could still be effective for the safety issue of hydrogen powered vehicles. To solve this problem, it is necessary to compare temperature characteristics of hydrogen-powered and traditional vehicle fires with and without longitudinal ventilations. In present work, we conducted a numerical investigation to discuss the different temperature distributions of traditional and hydrogen-fueled vehicle fires. Results indicate that the high temperature zone of the pool fire only exists above the ceiling of the vehicle. For hydrogen-powered vehicle fire, the high-speed hydrogen jet with the strong inertial force could push the hot smoke flows back to the ground. The ceiling temperature of hydrogen-powered vehicle fire is larger since hydrogen-powered vehicle has a larger heat release rate and the fire hazard of jet fires bring more danger compared with the pool fire. Although the temperature stratification is also obvious for the hydrogen-powered vehicle fire, the air temperature in the lower region could be heated and still high enough to bring a great damage to the passengers’ lives. This is quite different with the traditional pool fire. In addition, the critical ventilation velocity is also discussed. The theoretical equation could well predicted the critical ventilation velocity of traditional vehicle fires. For hydrogen-powered vehicle fires, the critical ventilation velocity could reach up to 6 m/s. The theoretical equation could not well predict the critical ventilation velocity of hydrogen-powered vehicle fires due to exist of hydrogen jet fires.