脱除废水中氨氮的传质动力学实验及模型计算

测定了废水中氨氮的脱除动力学数据,并建立合适的传质动力学模型对实验数据进行模拟计算。实验中考察了pH、温度、氨氮起始质量浓度等因素对动力学模型参数k的影响,在实验测定的范围内,k随着溶液pH增大而减小,随着溶液温度升高而减小。通过机理分析得到:增大pH和升高温度,促进了废水中氨氮的转化,对传质过程起到强化作用,提高过程进行的速率。为氨氮脱除动力学的进一步理论研究奠定基础,为过程设计提供一定的参考依据。     

系统辨识在空调房间建模上的应用

指出房间动态数学模型在控制系统中的重要性,简化了建立房间的理论数学模型,通过系统辨识的方法建立房间的模型,最后利用辨识的数学模型对阶跃响应的仿真结果和实测温度进行比较,从中可以选择所需精度的数学模型,进而考虑控制系统的设计和调节器参数的整定。     

600MW机组凝汽器汽侧流动与传热性能模拟

利用建立于PHOENICS操作平台上的凝汽器汽侧流场的三维模型，对某电厂600MW凝汽器壳侧复杂的混合物流动过程进行了计算模拟，并在此基础上做出了理论分析，找出了换热器性能薄弱的环节，提出了改造方案．计算结果与实验情况基本吻合。     

可重构装配系统中装配模块的可重构性研究

介绍了可以快速适应新产品装配生产的可重构装配系统概念，进行了可重构装配系统中装配模块的可重构性研究，提出将可重构装配模块的结构分为可重构接口模块、状态协调器模块和自治域模块三个部分的设计方案。在此基础上，构建了Scara仿真机器人装配模块和Motoman仿真机器人装配模块。通过可重构装配系统仿真实验证明，它们基本上符合可重构装配系统对于装配模块的要求。     

Comparison of Oxygen Transfer Parameters Determined from the Steady State Oxygen Uptake Rate and the Non-Steady-State Changing Power Level Methods

In this study, a laboratory scale Univ. of Cape Town enhanced biological phosphorus removal process was operated under controlled conditions at a solids retention time of 15 days. Results are presented for the process performance and oxygen transfer parameters determined by applying the steady state oxygen uptake rate (OUR) and the changing power level (CPL) techniques, as per ASCE standard guidelines. The testing periods were temporally separated to eliminate interference of the tests. During the application of the CPL method, the sludge volume index gradually increased and higher values of the oxygen transfer rate and alpha were measured, in comparison to the data from the steady state OUR method, under similar process performance. Furthermore, the mass transfer rate decreased as the CPL method of testing continued. In contrast, the oxygen transfer parameters remained uniform during the time when the OUR method was applied. The data indicated that the CPL method resulted in higher and variable oxygen transfer parameters, even though the process performance remained unchanged. Therefore, a more rigorous evaluation of the CPL method is recommended to clarify the validity of the test.     

超声波在线防垢、除垢与强化传热的实验研究

超声波防垢除垢与强化传热的机理是超声波的空化效应与机械效应.根据这一机理并由水力学计算,首次设计出了较完善的超声波防垢除垢及强化传热实验台,并确定防垢除垢与强化传热实验中所要控制的主要物理参数为:超声波频率、功率、反应体系温度.实验表明:适当提高超声波频率、功率和反应体系温度有利于提高清洗效率.     

浅析影响SCR法铸坯质量的因素

分析了SCR连铸连轧工艺生产铜银合金导线时,铸坯凝固的热阻界、铸模的传热条件、铸坯组织的控制对产品质量的影响。     

Risk Concession Model for Build/Operate/Transfer Contract Projects

This paper extends the build–operate–transfer (BOT) concession model (BOTCcM) to establishing a risk concession model for BOT contract projects. The decision for a concession period is one of the most important decisions in determining a BOT contract. BOTCcM presents an alternative method to assist in determining a concession period that can protect the basic interests of both the investor and the government concerned. However, there is a major limitation in using the model, namely it gives no consideration to the impacts of risks on the estimation of various economic variables in the model. This study considers the risk impacts to the BOTCcM model and presents an additional risk concession model. This model provides an approach for formulating a concession period to consider the impacts of risks and, at the same time, protect the basic interests of both the investor and the government concerned. A hypothetical case is used to show the procedures of formulating the risk concession period through the assistance of the Monte Carlo simulation method.     

同轴型热虹吸系统轴向传热特性实验研究

对一种用于冷中子源系统的自然循环进行了轴向传热特性研究,建立了以氟里昂为工质的同轴型热虹吸管传热实验系统。研究表明:同轴型热虹吸系统可强化轴向热传输能力,其传热工况有过冷沸腾流动振荡工况、稳定工况和烧干工况3类。在低功率区,过冷沸腾和携带机制造成启动过程的两相流振荡;进入稳定工况区后,系统具有自调适能力,能够维持恒定的循环质量流率;在高功率区,蒸发器烧干产生传热极限。本研究显示出同轴型热虹吸系统的动力特性与普通自然循环系统有明显区别,其循环机制与普通热虹吸系统有本质区别。