Development of fiberscope PIV system by controlling diode laser illumination

The objective of the present work is to establish a vector field imaging system using a PIV technique with an optical fiberscope. PIV has become a powerful tool due to its capability of measuring instantaneous velocity fields[Adrian 1991][Westerweel 1997], and PIV has contributed to highly accurate analysis of complex flows in combination with the scalar measurement of temperature[Sakakibara et al 1993]. However, where we actually investigate flows in closed vessels such as reactor, power plant, chemical plant, or combustor, illumination and recording of particle images become difficult and restricted because of the necessity of optical windows in appropriate positions. Another problem is that optical windows have a limited view restricted by a particular angle of optical access. The optical fiberscope makes it possible to thoroughly investigate internal condition without windows and is expected to become a successful diagnostic tool for industrial applications.