In reversed magnetic field as Fig. 2, there exists a stagnation point, where the accelaration of magnetic convection g is equal to the gravity accelaration g and the heat convection is cancelled.
The vertical coordinate X of the stagnation point is a function of O2% as shown by the equation (10).
Therefore, the O2% can be known by detecting the stagnation point. The test apparatus developped by the author is a balanced type O2-meter, which follows the stagnation point by two moving platinum wires driven by a two-phase motor which shifts them so as to decrease the temperature difference between them.
The apparatus operated well and some curves of stagnation point are obtained as shown in Fig. 9.
Some further study on heat convections, accuracy, and hunting of this system are described. As a conclusion, this method is a unique one of 02-meter and thought to have good future applicability for many systems of automation and especially for controlling O2%.
