REMOVABLE 

 MIRROR 



SPARK-GAP LIGHT SOURCE (0.032 in. DIA.) 



GATHERING LENS F.L. = 3 in. 



--^T I „0 STEADY LIGHT SOURCE 



~]^. COL LI MATING LENS 

 F.L. = 12 in.,/ 2.5 



WINDOWS (FLAT OR WITH 

 CORRECTOR LENS) 



TUNNEL TEST SECTION 



WITH HEATED BODY IN PLACE 



FOCUSING LENS 

 F.L. = 7 in.,/2.5 



J CUT-OFF PLATE 



FILM PLATE 



Figure 9 - Schlieren Flow Visualization System 

 (Lindgren and Johnsson 1966) 



19 



