V2F模型在室内空气流动数值模拟中与其他湍流模型的比较研究

介绍了V2F模型的表达式。对Annex20算例进行了模拟计算,将V2F模型、雷诺应力模型、标准K-ε模型、低雷诺数K-ε模型、RNGK-ε模型的模拟结果与其他研究者的实验结果进行了比较。结果表明,V2F模型在模拟室内空气流动中优于其他湍流模型。     

交通荷载作用下软土地基沉降分析

对软土地基在静力荷载作用下的沉降特性,交通荷载作用下软土的动力特性以及交通荷载作用下软土地基的沉降组成进行了分析,对工程实际有一定的借鉴作用。     

压差控制对变流量空调水系统水力稳定性的影响

分析了异程系统干管压差控制、异程系统末端压差控制、同程系统干管压差控制、同程系统末端压差控制、环形管网干管压差控制和环形管网末端压差控制对变流量空调水系统水力稳定性的影响.计算结果表明,同程系统、环形管网末端压差控制具有最好的水力稳定性.     

Simulation-based optimization method for arterial signal control considering traffic safety and efficiency under uncertainties

This paper proposes an arterial signal control stochastic simulation-based optimization model with traffic safety and efficiency as biobjectives and solves it by a biobjective surrogate-based promising area search (BOSPAS) method. In this model, traffic safety and efficiency are indexed by the average potential collision energy (APCE) and the vehicular throughput of the arterial road, respectively, and the arterial signal control plan is designed in a ring-and-barrier structure. In the BOSPAS method, each solution is evaluated by traffic simulation only once and stochastic evaluation noises of the sampled solutions are smoothed by a shrinking ball method to approximate their biobjective expectations. Based on the solutions and their estimated biobjective values, two surrogate models of biobjectives are constructed and optimized to obtain the nondominated solutions, which will guide the establishment of the joint promising area for sampling in the next iteration. In the numerical experiments, BOSPAS is first tested to outperform three other counterparts (i.e., nondominated sorting genetic algorithm II [NSGA-II], biobjective efficient global optimization [BOEGO], and biobjective promising area search [BOPAS]) by a stochastic FON function from the aspects of convergence and diversity. It is then applied to optimize the signal control plan of an arterial road with six four-leg signalized intersections in Changsha, China. The numerical results show that the nondominated solutions by BOSPAS perform better than those by NSGA-II, BOEGO, and BOPAS under limited simulation budgets, and also mostly outperform three solutions by Synchro, MAXBAND, and MULTIBAND, especially in reducing APCE. In contrast with the field-implemented signal plan, the optimized ones by BOSPAS improve the APCE and the vehicular throughput of the arterial road by at most 50.2% and 24.8%, respectively. Moreover, considering the vehicular throughput of arterial road as one objective may have a negative effect on the vehicular throughput of the overall road network. In conclusion, BOSPAS is promising to address biobjective optimization problems characterized by costly evaluation, high dimensions, and stochastic noises.     

新风系统经济运行控制策略的分析与研究

分析了在定风量系统中实现经济运行的温度控制原则，提出了考虑室内温度控制的新风系统经济运行控制策略，利用模拟程序对不同控制策略下的空调系统能耗进行了比较和分析。     

空调水系统中定压差控制水力平衡措施相关问题探讨(一)——自力式压差平衡阀的选型

为了更好地研究定压差控制对电动调节阀实际流量特性的改善程度,提出了自力式压差平衡阀选型的三要素:阀门公称压力、控制压差和流量系数。分析了四类典型空调水系统中各末端自力式压差平衡阀的计算工况,并按某算例对各系统的末端自力式压差平衡阀进行了实际选型。     

温湿度独立控制空调系统和常规空调系统的性能比较

选择北京和广州相同的办公楼作为比较对象,常规空调系统采用典型的风机盘管+独立新风的形式。应用DeST软件计算了建筑全年逐时冷负荷,计算了两个系统的能效比EER(energy efficiency ratio)和能耗。结果表明,对于北京的办公建筑,温湿度独立控制空调系统全年能耗为14.75k Wh/m2,EER为4.5;常规空调系统全年能耗为18.63k Wh/m2,EER为3.6。对于广州的办公建筑,温湿度独立控制空调系统全年能耗为32.66k Wh/m2,EER为4.5;常规空调系统全年能耗为43.39k Wh/m2,EER为3.4。相比常规空调系统,温湿度独立控制空调系统的节能率在20%～30%。     

垂向射流与挡烟垂壁组合控制烟气蔓延研究

利用FDS模拟走廊中设置垂向射流与挡烟垂壁组合方式对高层建筑火灾烟气控制效果的影响.比较几种火灾模式下烟气的温度、浓度分布.结果表明,采用垂向射流与机械排烟结合的烟气控制模式比单纯机械排烟的效果明显提高;前室部分加压并在前室门前2 m处设置垂向射流,同时在垂向射流和机械排烟口之间布置挡烟垂壁的组合控制模式具有最佳的烟气控制效果.     

医院病房人流量特征及新风量需求

提出了影响病房新风量的两个特征参数——人员数量和人员在室停留时间,结合调研数据,给出了不同科室的人员数量及停留时间特征。提出了抗冲击能力强度与抗冲击时间两个新风供应能力参数,建立了基于此参数的病房新风调控判据。根据算例分析,认为病房新风设计换气次数值宜大于2h-1,并提出了调控策略。     

交通荷载作用下高液限粘土路基稳定性分析

依托某高速公路高液限土路基,利用数值模拟技术对其进行动力稳定性分析。结果表明:交通荷载作用下,高液限土路基顶部位置稳定性最差,且路基路面中部位置沉降量最大,相应的成为容易产生道路病害的位置;高液限土路基靠近边坡的位置为稳定性较差的位置,易造成边坡滑塌等现象;改良后的高液限土路基沉降量和横向位移明显得到控制。