| 摘要 |
<p>PURPOSE:To measure the flow rate of a pulsating flow highly accurately, by making the inertial length of a bypass longer than the fluid inertial length between the pressure difference taking out ports of the main stream, thereby compensating the response delay of the hot wire. CONSTITUTION:The pressure difference ports 3 and 4 which are connected to annular paths 12 and 13 are provided at the upstream and the narrowest part of a Venturi member 2 in a main path 1. The annular paths 12 and 13 are connected by the bypass 6 which is constituted by a descending path 14 and a returning path 15. The pressure difference=flow rate of the bypass is measured by the hot wire 7 and a temperature compensating resistor 8 which are provided in a part of said bypass 6. The relationship with regard to l, D, and L is set to be L/D=0.1-1 and l>L, where l is the length of the bypass, D is the diameter of the main path 5, and L is the length between the pressure difference ports 3 and 4. Then the error due to the response delay in the hot wire can be compensated by the inertial effect of the flow in the bypass, and the error in flow rate measurement can be reduced.</p> |
