In this p
aper, the infot
axis-b
ased se
arch
algorithm is tested in sever
al simul
ated turbulent ch
annel flows. The
algorithm is
ad
apted to detect plumes of high concentr
ation inste
ad of independent p
articles. Direct numeric
al simul
ation is used to test this
ad
apted se
arch
algorithm by detection of high concentr
ation levels in turbulent ch
annel flows with
a Schmidt number
an id="mmlsi51" class="mathmlsrc">an class="formulatext stixSupport mathImg" data-mathURL="/science?_ob=MathURL&_method=retrieve&_eid=1-s2.0-S0377042716302746&_mathId=si51.gif&_user=111111111&_pii=S0377042716302746&_rdoc=1&_issn=03770427&md5=ef6dfc01cd952341ea9ae897065461c1" title="Click to view the MathML source">Scan>an class="mathContainer hidden">an class="mathCode">ath altimg="si51.gif" overflow="scroll">Scath>an>an>an> of 1.0
and Reynolds numbers
an id="mmlsi52" class="mathmlsrc">an class="formulatext stixSupport mathImg" data-mathURL="/science?_ob=MathURL&_method=retrieve&_eid=1-s2.0-S0377042716302746&_mathId=si52.gif&_user=111111111&_pii=S0377042716302746&_rdoc=1&_issn=03770427&md5=9fcf6e51a92da6a04602a3e17f315567" title="Click to view the MathML source">Rean>an class="mathContainer hidden">an class="mathCode">ath altimg="si52.gif" overflow="scroll">Reath>an>an>an> of 5600
and 28000.
For the direct numerical simulation with the adapted algorithm, there is a positive relation between the initial distances to the source and the running time, which holds for an id="mmlsi53" class="mathmlsrc">an class="formulatext stixSupport mathImg" data-mathURL="/science?_ob=MathURL&_method=retrieve&_eid=1-s2.0-S0377042716302746&_mathId=si53.gif&_user=111111111&_pii=S0377042716302746&_rdoc=1&_issn=03770427&md5=cf6e218c02bc9cb79d507fc7d2495150" title="Click to view the MathML source">Re=5600an>an class="mathContainer hidden">an class="mathCode">ath altimg="si53.gif" overflow="scroll">Re=5600ath>an>an>an> but which is not observed at an id="mmlsi54" class="mathmlsrc">an class="formulatext stixSupport mathImg" data-mathURL="/science?_ob=MathURL&_method=retrieve&_eid=1-s2.0-S0377042716302746&_mathId=si54.gif&_user=111111111&_pii=S0377042716302746&_rdoc=1&_issn=03770427&md5=1d12cb18cdf8a76fb5cd71500efb49d4" title="Click to view the MathML source">Re=28000an>an class="mathContainer hidden">an class="mathCode">ath altimg="si54.gif" overflow="scroll">Re=28000ath>an>an>an>. This is caused by the low Schmidt number and the high velocity, which leads the searcher to the source very fast after the first detection of a high concentration level.
The search algorithm is also tested in reverse to detect whether a fluid is well-mixed. The time required for a detection of a too high or low concentration and the number of detections are used as measures for success. By applying the algorithm to some prescribed concentration distributions in two dimensions, it is found that the method is very sensitive to the threshold values for the mixing indicators.