Weight loss on heating of the body in various liquids
DOI:
https://doi.org/10.17072/1994-3598-2017-1-26-30Abstract
The effect of heating on the change in the weight of a heated body in two different liquids has been experimentally studied. The cone was used, made of the Rose alloy, inside which the resistor was located. During the study, the weighing was carried out in a body placed in a liquid. It is shown that the maximum body temperature in glycerin at the same heat source power is 2.5 times higher than the body temperature in water. For both liquids, it was found that at the initial moment the body weight decreased, and then began to increase. At the time of power supply disconnection, a sharp increase in weight was observed and after the end of the experiment its value turned out to be less than the initial value. This is explained by the fact that when convective currents arise on a body immersed in a liquid, the additional force begins to act, which pushes the body out of the liquid, and as a consequence, the body weight decreases. The subsequent increase in weight is associated with a change in the temperature and density of the fluid near the body, and at the time of switching off the heating, a decrease in weight is caused by a weakening of the convective currents. Structural flows were studied using the laser knife method. By adding fluorescent dyes to glycerin, a picture of the convective currents in the plane of the laser knife was obtained, and mean velocities were found by means of a suspension of light reflecting particles. The velocity in the boundary layer is maximal, in water it reached 3.4 mm / s, in connection with which, the body weight decreased by 0.03%. The greatest change in weight was observed in glycerol and amounted to 0.13%.Received 19.03.2017; accepted 05.05.2017References
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