PROBLEMS OF INTERPRETATION OF HOLOGRAPHIC INTERFEROGRAMS NEAR SHOCK-WAVE FRONTS

A method of avoiding ambiguity in the interpretation of interferograms near a shock wave front is proposed. The method is based on combining the double-exposure schlieren method and holographic interferometry. Relations for calculating, on the basis of data obtained by analyzing double-exposure schlieren photographs, both the density at the shock w ave front and the gradient of the density directly behind the front, w hich is necessary for calculating the shifts of the interference fring es near the shock wave front, are presented. (C) 1998 American Institu te of Physics. [S1063-7842(98)01709-7].