307 



1,0 



2.0 



3.0 



^.0 



5.0 



5,0 



7.0 



Relative intensity 



] St -Sol 



Seowater. 271077 (One-tiole aperture) 



Slandord -Solution: D = 257 urn. Cpg.i = 1.0 ■ 10'' n/cm-* 28.1077 ' 



St -Sol 



D = 25.7 yum. Cpon = 5i n/cmJ 

 D = 25.7^m. cpori = 5 nlctri' 



31.10 77 

 11177 



St-Sol. lor particle size 

 D=25.7|um 



SI -Sol 



D = 1.011 urn. Coon = 1.76 ■ 10" n/cm-i 231T77' 



St-Sol 



D = 1.011 <jm: Cixiri =1,76 1CPnycm-i 



St-Sol D = 1.011um 



St-Sol C 



Seowater 28. 10 77 



31 1077 



2 1177 



2.11.77. 



Swan-River 



Port Ptiillip Boy 



J Cpcri =1.75 105 n/cm^ 



: 1.011 pm. Cpori = 1,75 lO^n/cm^ 



20 naut. miles betore Fremantle 

 I 311 77; Fremantle 

 711,77 



] 2311 77 

 23.1177 

 2311 77 



-,.100 

 1^ — lRel.:nt 



-Sol. for particle size 

 = 1.011 pm 



Melbourne 



11.1177 Swonson Dock West 



Sydney 



2011 77; White Bay 



39 

 1 Rel.Dnt. 



] Seowater 221177 



231177 



I 2i.11 77 



Swan -River 



Seowater 212 77 



512 77 IGulf of Aden) 

 5.12,77 



^Seowater 712,77 (Shallow water. Bob-el-Mondob) 



I] " 712 77 (■■ 



71277 (Red Sea) 



some sample after 6 hours) 



Seowater 



1012.77 Greot Bitter Lake 



Seowoter 



Seawoter 



11 1277 (Mediterranean. 15 naut. miles behind Port Said) 

 12.1277 (Ionian Sea) 



FIGURE 10. Measured suspended particles. 



Measurements of Total Air Content 



Although the water should always just be saturated 

 at the surface, the gas concentration c of the 

 sea water was also continuously determined from 

 water samples with a Van-Slyke-apparatus . The 

 results are given in Figure 11, in dependence of 

 the temperature. 



For the calculation of the gas content ratio, 

 e = c /c , the gas saturation capacity, c , is 

 necessary for the specific salt content and temper- 

 ature. Since the corresponding data were not known 

 some water samples were left overnight in a basin 

 wilih a large surface and the gas concentration c 

 was determined on the following day, which in this 

 case should indeed correspond to the saturation 

 concentration c . The two values obtained for the 

 saturation concentration c are also plotted in 

 Figure 11 (witih the symbol -y- ) . They are witiiin 

 the range of tolerance of the measured total gas 

 content , Cq , for the voyage leading southward . 

 Subsequently the measured total gas content present 

 values which correspond to the gas content ratio, 

 £ = 1, i.e., to saturated water. Due to the 

 dissolved salt the total gas content values, Cq, 

 for sea water should lie below the values for fresh 

 water. This is, in fact, the case with tine exception 

 of some values of the voyage leading northward. It 

 must be left to other investigations to find out 

 whetiher the wind, seaway, and temperature "history" 

 of the sea surface has an influence on the total 

 gas content. 



5. MEASUREMENTS OF THE NUCLEI SPECTRA AND LOCAL 

 VELOCITY 



Device for Nuclei Measurement 



The LSL method was applied to the measurement of 

 the nuclei spectra in front of the "Sydney Express" 



propeller. This method was also applied to the 

 model tests, described by Keller and Weitendorf 

 (1975) . Detailed information about the measure- 

 ment principle has been supplied, for instance, by 

 Keller (1970, 1973). Thus, it is not necessary 

 to go into the details. 



Compared with previous measurements carried out 

 in the laboratory the measuring distances were 

 essentially larger at these full scale investigations. 

 Thus, some new components for the measuring device 

 were required. The distance between the measuring 

 volume and the receiving lens amounted up to 2 m so 

 that the laser power and the diameter of tiie 

 receiving lens had to be markedly increased, in 

 order to obtain usuable measuring signals. 



The arrangement of the measuring unit on board 

 is shown in Figures 1 and 2. The path of the laser 

 beam is bent tJiree times and enters the water almost 

 horizontally; the path of the beam of the receiving 

 system is bent once and proceeds in the water 

 vertically. With this arrangement the flow direction 



I Co 

 i'U] 



20 - 



12 ■ 



2 - 





.- Saturation of air in pure water (70 mm Hg ) 



YzTfj. Measured total air content in seawoter southbound voyage 



-f -f Measured total air content in seowater northbound voyage 



-^ Saturation of air in seawater 



•1) Port Phillip Bay (Melbourne, 7. 11.1977) 



10 



15 



20 



25 



30 ^°C 

 T 



FIGURE 11. Measured total air-content. 



