| 摘要 |
<p>PURPOSE:To attain measurement of flow rate in a wide range covering from a laminar flow through a turbulent flow region with simple constitution, by using a material serving also as a conductive material and a heating temperature measurement-resistant material to form a sensor main body and then making use of the heat transmission of a boundary layer. CONSTITUTION:A part of a basin wall surface of a fluid to be measured is formed with a heating temperature measurement-resistant material, and heating terminals HT.T are provided together with temperature measuring terminal electrodes ED1 and ED2. If the fluid temperature is set at t1 when the fluid flows an area having no throttle part at a speed v1, the electric resistance is R1 between temperature measuring terminals 1 and 2. An area having a throttle part is heated up to a surface temperature t2 since a heating current flows between heat terminals 5 and 6. Furthermore, the difference between temperatures t1 and t2 is kept constant. In this case, the electric resistance is set at R2 between the terminals 3 and 4. Then a throttle part is provided, and the speed of fluid is accelerated to v2 from v1, and therefore, the quantity of heat absorbed from the throttle surface increases. This meter increases the speed of response and improves the accuracy for measurement of a micro current. The throttling is increased with more minute flow rate, and the speed v2 is increased. Thus the dissipated heat quantity is increased. Then the detection is possible for the flow rate of a boundary layer.</p> |
