ZHUANG Qi-ren, GONG Dong-mei, TAO Hai-min, et al. A quick measuring method for liquid surface tension by laser beam[J]. Optics and precision engineering, 2007, 15(5): 662-667.
ZHUANG Qi-ren, GONG Dong-mei, TAO Hai-min, et al. A quick measuring method for liquid surface tension by laser beam[J]. Optics and precision engineering, 2007, 15(5): 662-667.DOI:
A new quick measuring method for liquid surface tension by a parallel rectangle beam of diode laser and two pieces of linear array CCD sensors is presented. To avoid individual influence
liquid surface tension is measured by detecting angles of incidence at cylindrical liquid menisci instead of detecting climb height of liquid on flashboard. The relation between surface tension and the angle of incidence
and calculation formulas for the incidence angle measured with CCDs are developed based on the fundamentals of plate insertion method
the parameters are designed
and their errors are analyzed.The analysis shows that by a wider laser beam and big incidence angles
as well as keeping a long distance between two CCD sensors
the accuracy of liquid surface tension measurement will be improved. It is also found that the width detecting errors of laser beam is an important factor to accuracy of liquid surface tension measurement. For example
to measure water surface tension with a laser beam width of 1 mm and errors of 5 μm
the surface tension measurement accuracy is 1%. If reduce the beam width errors to 2 μm
the surface tension measurement accuracy will be 0.5%. Experimental results have proved that the surface tension of water measurement accuracy is better than 1% with this method.