MEASUREMENT TECHNIQUE FOR SPATIAL DISTRIBUTION OF LIQUID OR GAS FLOW VELOCITY (OPTIONS) Russian patent published in 1998 - IPC

FIELD: measurement technology. SUBSTANCE: spatial distribution of flow velocity V(x) is determined by single long semiconductor thermal element. Measurement technique is based on dependence between heat loss of thermal element built around three-layer p-n-p or n-p-n structure of length L which is continuously heated by DC current J_H and speed of liquid or gas wherein thermal element is placed. Heating DC current J_H is passed through p or n layer from voltage supply E connected to two leads of p or n layer and voltage U is applied between one of p or n layer leads and p or n layer. I(U) as function of is measured and this function is used to determine distribution of local density of reverse saturation current j(x) along thermal element. Distribution V(x) is found from j(x) distribution and from pre-determined j(V) dependence which is density of reverse saturation current as function flow velocity. EFFECT: improved measurement accuracy. 6 dwg