Based on K ε two equation turbulence model,the air distribution and contamination field under different conditions was numerically simulated in a vector flow cleanroom.Special mesh system was introduced to deal wit...Based on K ε two equation turbulence model,the air distribution and contamination field under different conditions was numerically simulated in a vector flow cleanroom.Special mesh system was introduced to deal with the quarter circle shaped inlets.Model experiments were also made.By analysis of numerical as well as experimental results,we made some predictions about flow characteristics,contaminant control effect and ventilation performance of this energy saving cleanroom.It has been proved that the vector flow can meet class 100 of Fed. St.with 13 to 12 conventional air change per hour,and reduce layer height and simplify air clean system.展开更多
Keeping pressure gradient is an excellent approach to prevent the reveal of </span><span style="font-family:"white-space:normal;">airflow direction and cross infection in manufacturing ...Keeping pressure gradient is an excellent approach to prevent the reveal of </span><span style="font-family:"white-space:normal;">airflow direction and cross infection in manufacturing circumstances of ph</span><span style="font-family:"white-space:normal;">armaceutical cleanrooms, thus how to keep cleanroom’s pressure is critical. In </span><span style="font-family:"white-space:normal;">the paper, we study a positive pressure pharmaceutical cleanroom system wh</span><span style="font-family:"white-space:normal;">ich is composed by a cleanroom and an airlock. We divide the system’s disturbances into step disturbance, ramp disturbance and sine wave disturbance. </span><span style="font-family:"white-space:normal;">We design its pressure gradient control strategies, including CAV control, PI</span><span style="font-family:"white-space:normal;">D control and active-disturbance-rejection-control. We build the system’s mod</span><span style="font-family:"white-space:normal;">el and make simulations based on Matlab/Simulink software platform. Re</span><span style="font-family:"white-space:normal;">sults show that active-disturbance-rejection-control algorithm has good capabilities for shorter responding time and lower overshot of the pressure gradient. The results reveal that active-disturbance-rejection-control method has good control performances in responding time, accuracy and disturbance rejection.展开更多
Cleanroom software engineering has been proven effective in improving software development quality while at the same time increasing reliability. To adapt to large software system development, the paper presents an ex...Cleanroom software engineering has been proven effective in improving software development quality while at the same time increasing reliability. To adapt to large software system development, the paper presents an extended the Cleanroom model, which integrates object-oriented method based on stimulus history, reversed engineering idea, automatic testing and reliability assessment into software development. The paper discusses the architecture and realizing technology of ECM.展开更多
This summary has introduced the development process of clean technology, and demonstrated the current status and development of cleanroom and relevant environment technology at home and abroad.
Pressure differential deviations under static conditions and pressure convergence fluctuations under dynamic disturbances are widely reported problems with pressure differential control in pharmaceutical cleanrooms,ye...Pressure differential deviations under static conditions and pressure convergence fluctuations under dynamic disturbances are widely reported problems with pressure differential control in pharmaceutical cleanrooms,yet their underlying mechanisms and key reasons remain insufficiently explored.This study performed a field survey and model-based simulations to identify the major influencing parameters and quantify their influence on pressure differentials.Twelve pharmaceutical cleanrooms with varying environmental control parameters were included in the field survey,all of which were served by a variable air volume(VAV)ventilation system.Large deviations between actual and design pressure differentials were found,ranging from 10%to 42.5%,and a total of 24 uncertain parameters and their respective uncertainty ranges were identified.Based on the field survey,a data-driven pressure differential response model was developed using MATLAB/Simulink platform.The model fully took into account the system dynamics and facilitated real-time monitoring and control of the pressure differential.Sobol-based sensitivity analysis was then conducted to identify key influencing parameters of pressure differential deviations.The simulated results revealed that static pressure differential deviations were predominantly influenced by pressure sensing accuracy,exhaust airflow accuracy,and duct impedance,while dynamic disturbances were mainly driven by room envelope airtightness and supply airflow accuracy.The interactions between connected zones were pronounced.Rooms with higher branch duct impedance experienced smaller pressure differential deviations due to natural buffering characteristics,while the parameter uncertainties in these rooms significantly affected pressure differential in other rooms.These findings offer practical guidance for the design and operation of precise pressure differential control in pharmaceutical cleanrooms.展开更多
目的通过组织实施换气次数检测实验室能力验证计划,探索实验动物设施环境领域能力验证方式,初步了解相关实验室在标准应用及检测水平的现状,规范换气次数检测方法,确保检测结果的准确性和可靠性。方法2023年9—11月,中国食品药品检定研...目的通过组织实施换气次数检测实验室能力验证计划,探索实验动物设施环境领域能力验证方式,初步了解相关实验室在标准应用及检测水平的现状,规范换气次数检测方法,确保检测结果的准确性和可靠性。方法2023年9—11月,中国食品药品检定研究院负责组织开展实验动物设施换气次数检测的实验室能力验证计划(编号NIFDC-PT-417)。此次能力验证计划的现场测试分为两个部分:笔试和实际操作。笔试采用开卷形式,判断题着重考察参加者对标准条款的掌握情况,应用题则是通过构建模拟检测场景考察实验人员对数据处理的应用;实际操作按照中国合格评定国家认可委员会(China National Accreditation Service for Conformity Assessment,CNAS)相关准则,通过分割水平样品对的形式,准备2个实验房间作为能力验证样品。2个房间均按照CNAS相关要求,经过均匀性、稳定性测试,并且测试结果合格。参与能力验证的实验室需要对这2个实验间各进行3次测试,要求在规定时间内完成换气次数的检测和计算,并提交本次检测的结果报告单和原始记录。结果共有27家实验室报名并参加本次能力验证,均在规定时间内反馈结果,所有参测实验室的结果均被评定为满意。结论本次能力验证客观且科学地评估了国内部分实验室在换气次数方面的检测能力,有效地促进了行业整体检测水平的提升,为监管部门规范检测机构提供了技术支撑,为委托单位购买检测服务提供了可靠的参考依据。通过本次能力验证,组织方发现部分实验室对仪器的校准及校准结果的利用不够充分,未来需进一步完善相关标准,以提高检测的准确性和可靠性。展开更多
文摘Based on K ε two equation turbulence model,the air distribution and contamination field under different conditions was numerically simulated in a vector flow cleanroom.Special mesh system was introduced to deal with the quarter circle shaped inlets.Model experiments were also made.By analysis of numerical as well as experimental results,we made some predictions about flow characteristics,contaminant control effect and ventilation performance of this energy saving cleanroom.It has been proved that the vector flow can meet class 100 of Fed. St.with 13 to 12 conventional air change per hour,and reduce layer height and simplify air clean system.
文摘Keeping pressure gradient is an excellent approach to prevent the reveal of </span><span style="font-family:"white-space:normal;">airflow direction and cross infection in manufacturing circumstances of ph</span><span style="font-family:"white-space:normal;">armaceutical cleanrooms, thus how to keep cleanroom’s pressure is critical. In </span><span style="font-family:"white-space:normal;">the paper, we study a positive pressure pharmaceutical cleanroom system wh</span><span style="font-family:"white-space:normal;">ich is composed by a cleanroom and an airlock. We divide the system’s disturbances into step disturbance, ramp disturbance and sine wave disturbance. </span><span style="font-family:"white-space:normal;">We design its pressure gradient control strategies, including CAV control, PI</span><span style="font-family:"white-space:normal;">D control and active-disturbance-rejection-control. We build the system’s mod</span><span style="font-family:"white-space:normal;">el and make simulations based on Matlab/Simulink software platform. Re</span><span style="font-family:"white-space:normal;">sults show that active-disturbance-rejection-control algorithm has good capabilities for shorter responding time and lower overshot of the pressure gradient. The results reveal that active-disturbance-rejection-control method has good control performances in responding time, accuracy and disturbance rejection.
文摘Cleanroom software engineering has been proven effective in improving software development quality while at the same time increasing reliability. To adapt to large software system development, the paper presents an extended the Cleanroom model, which integrates object-oriented method based on stimulus history, reversed engineering idea, automatic testing and reliability assessment into software development. The paper discusses the architecture and realizing technology of ECM.
文摘This summary has introduced the development process of clean technology, and demonstrated the current status and development of cleanroom and relevant environment technology at home and abroad.
基金supported by the Natural Science Foundation of Hunan Province of China(No.2024JJ9082)by the Fundamental Research Funds for the Central Universities(No.531118010378).
文摘Pressure differential deviations under static conditions and pressure convergence fluctuations under dynamic disturbances are widely reported problems with pressure differential control in pharmaceutical cleanrooms,yet their underlying mechanisms and key reasons remain insufficiently explored.This study performed a field survey and model-based simulations to identify the major influencing parameters and quantify their influence on pressure differentials.Twelve pharmaceutical cleanrooms with varying environmental control parameters were included in the field survey,all of which were served by a variable air volume(VAV)ventilation system.Large deviations between actual and design pressure differentials were found,ranging from 10%to 42.5%,and a total of 24 uncertain parameters and their respective uncertainty ranges were identified.Based on the field survey,a data-driven pressure differential response model was developed using MATLAB/Simulink platform.The model fully took into account the system dynamics and facilitated real-time monitoring and control of the pressure differential.Sobol-based sensitivity analysis was then conducted to identify key influencing parameters of pressure differential deviations.The simulated results revealed that static pressure differential deviations were predominantly influenced by pressure sensing accuracy,exhaust airflow accuracy,and duct impedance,while dynamic disturbances were mainly driven by room envelope airtightness and supply airflow accuracy.The interactions between connected zones were pronounced.Rooms with higher branch duct impedance experienced smaller pressure differential deviations due to natural buffering characteristics,while the parameter uncertainties in these rooms significantly affected pressure differential in other rooms.These findings offer practical guidance for the design and operation of precise pressure differential control in pharmaceutical cleanrooms.
文摘目的通过组织实施换气次数检测实验室能力验证计划,探索实验动物设施环境领域能力验证方式,初步了解相关实验室在标准应用及检测水平的现状,规范换气次数检测方法,确保检测结果的准确性和可靠性。方法2023年9—11月,中国食品药品检定研究院负责组织开展实验动物设施换气次数检测的实验室能力验证计划(编号NIFDC-PT-417)。此次能力验证计划的现场测试分为两个部分:笔试和实际操作。笔试采用开卷形式,判断题着重考察参加者对标准条款的掌握情况,应用题则是通过构建模拟检测场景考察实验人员对数据处理的应用;实际操作按照中国合格评定国家认可委员会(China National Accreditation Service for Conformity Assessment,CNAS)相关准则,通过分割水平样品对的形式,准备2个实验房间作为能力验证样品。2个房间均按照CNAS相关要求,经过均匀性、稳定性测试,并且测试结果合格。参与能力验证的实验室需要对这2个实验间各进行3次测试,要求在规定时间内完成换气次数的检测和计算,并提交本次检测的结果报告单和原始记录。结果共有27家实验室报名并参加本次能力验证,均在规定时间内反馈结果,所有参测实验室的结果均被评定为满意。结论本次能力验证客观且科学地评估了国内部分实验室在换气次数方面的检测能力,有效地促进了行业整体检测水平的提升,为监管部门规范检测机构提供了技术支撑,为委托单位购买检测服务提供了可靠的参考依据。通过本次能力验证,组织方发现部分实验室对仪器的校准及校准结果的利用不够充分,未来需进一步完善相关标准,以提高检测的准确性和可靠性。
