For the adsorption of exhaust gas in multiple parallel towers, how can the air flow be distributed evenly?

The even distribution of air volume when multiple towers are used in parallel for the adsorption of exhaust gas can be achieved through the following methods: 1. Install flow meters on each of the towers for exhaust gas, and adjust the distribution of air volume by monitoring the exhaust gas flow rate in each tower； 2. Control valves are installed at the air inlets to each tower, and the distribution of air volume is adjusted by manually or automatically controlling the degree to which these valves are opened ； 3. For multi-tower adsorption systems powered by a single fan, branch pipes and control valves can be installed to distribute the air volume proportionally among the different towers ； 4. Use numerical simulation software such as CFD to analyze and optimize the exhaust gas flow fields of each tower, in order to further determine a reasonable air volume distribution scheme. .

Calculate the resistance of each tower; once the resistances are equal, the air flow rates for each tower will also be equal

How can this be achieved in terms of automatic control?