| Abstract: | Use of tomographic measuring techniques for process engineering studies . Tomographic measuring techniques have so far been employed almost exclusively in medicine and for testing of materials. They permit determination of experimental values for all local coordinates of a given volume at a given time. Classical tomography can be used for measurements only in stationary fields of flow, temperature, and concentration since the object has to be irradiated from as many directions as possible during a finite time interval. In the case of transient events, however, it is necessary to acquire all these values at the same point in time. If transparent fluids are present then coherent light is suitable for irradiation and holographic interferometry for recording the measured values. Since irradiation must take place simultaneously from several directions, the number of recording angles should be kept to a minimum. It is also necessary to employ mathematical procedures for image reconstruction in order to ensure adequate accuracy of the measured values. |
