THE STRUCTURE OF A TURBULENT WATER-JET

EXPERIMENTAL STUDIES ARE MADE TO DETERMINE THE STRUCTURE OF A TURBULENT WATER JET.THE PAPER IS DIVIDED INTO TWO PARTS.THE FIRST GIVES PRACTICAL INFORMATION ABOUT THE TECHNIQUES AND INSTRUMENTATION DEVELOPED TO MAKE MEASUREMENTS WITH HOT-WIRE ANEMOMETERS IN WATER.A SHORT THEORETICAL DISCUSSION IS GIVEN ON THE DYNAMIC RESPONSE OF HEATED FIBRE IN LIQUIDS.THE SECOND PART REPORTS ON THE RESULTS OBTAINED IN A ONE-INCH WATER JET AT REYNOLDS NUMBERS BETWEEN 12,000 AND 20,000.MEAN AXIAL VELOCITY MEASUREMENTS ARE MADE IN THE INITIAL FIVE DIAMETERS OF THE JET AND THE RESULTS ARE USED TO PREDICT THE NATURE OF THE VORTEX SHED AT THE JET LIP.SPECTRUM MEASUREMENTS ARE MADE IN THE SAME POSITION USING AN ANALOGUE TO DIGITAL CONVERTER AND COMPUTER TO PROCESS THE DATA.THE MEASUREMENTS ARE DISCUSSED IN RELATION TO THE STRUCTURE OF THE JET AND THE FORMATION OF VORTICES AT THE JET LIP.(A).