Is the inner diameter of the exhaust port outlet the diameter?

[McKing]

Yes, generally speaking, the diameter of the inner circle of a circular object is called the inner diameter. How to set the inner diameter of the exhaust pipe outlet: The two parameters, exhaust gas velocity and inner diameter of the outlet, are directly related to the amount of exhaust gas discharged from the exhaust pipe. The amount of exhaust gas passing through the chimney outlet per unit time (i.e., the exhaust rate Qv) divided by the area of the chimney outlet is the exhaust gas velocity Vs. The exhaust gas velocity Vs of the exhaust pipe must not be less than 1.5 times the wind speed Vc calculated according to the method specified in Section 5.6.1 of GB/T13201. Drainage pipe issues: Common problems with car air conditioning drainage pipes include aging, loosening, or bending into a wavy shape due to long-term use, which can cause poor drainage and partial blockage. The solution is to contact the manufacturer or a qualified air conditioning repair technician to replace the drainage pipe.