Confined Impinging Jet Geometry
 

I have a question about the configuration and setup of an Impinging Confined jet. My teacher has assigned a setup of:

inlet jet diameter= 4mm
inlet jet length= 58mm
confined gap height= 1mm
impinging surface diameter= 38mm

I am unsure of what she means by the inlet jet length and the confined gap height. Is the confined gap height the distance between the impinging surface and the nozzle exit, or am I way off base?

Any help is greatly appreciated.