A challenge and decision in the clean room design process is how to determine the required supply air volume to achieve the target cleanliness classification in a given application. Historically, these decisions are made based on experience and following practices and guidelines that have evolved from multiple sources which we can today say have been conservative at best.
Following these practices will supply enough clean air to meet the classification requirements, however at the expense of overdesigning the system with higher capital costs and by default, higher operating costs than necessary. Also, if the experience based approach leads to underestimating the supply air rate, the result could be contamination levels that are too high and costly work to fix the problem. AAF Flanders has developed a scientific approach to this problem for predicting the contamination in a clean room based on sources of particle generation, air filter efficiency and air change rate.
VisionAir Clean is a web based application that allows the user to see factors that impact indoor air quality and energy consumption related to the air filtration system. Starting from the PM 2.5 levels in the outdoor environment, this program displays the particle count in a room as a function of the air change rate and compares it to the selected cleanliness standard requirements. VisionAir Clean also accounts for particle generation within the clean spaces, such as people in various garment types and process related contamination, and shows the changes in contamination as inputs are modified. Filter test data are loaded into the program to estimate filter life and optimize the change-out cycle based on balancing the costs associated with the filter (purchase price, labor, disposal, etc…) and the energy consumption as the filter resistance increases with dust load. The energy cost impact due to resistance across housing components, such as dampers and diffusers, are also taken into account.
The output of this analysis is an optimized solution for air filtration applications, specifications, drawings and models of products, reports indicating total cost of ownership and air quality, a 3D visualization of the products and a technical library of relevant industry information...
Session: G17 - Monitoring and Control
Day: 24 October 2019
Time: 14:45 - 16:00 h