Abstract
Taiwan plays an important role in the whole world on the fan and forced draught blower market. Taiwan must set the standard for its flow of fan to make the dependable basis. AMCA wind-tunnel generally used in such fan function tests of heat dissipation as CPU of IT industry,etc. the correcting of the flow meter usually send to Inspection Bureau of the national standard but there are some disadvantages in high cost. This thesis studies the feasible method to correct instrument and equipment. In the small flow, we use the device with the compressibility factor Theory (PV =ZmRT) to correct the amount of air flow. In order to calculate the total amount of air through wind tunnel, we precisely,we design a tank. After a while, the air passing through wind tunnel is selected into the tank. We observe the difference of height in water level in U monometer and calculate the pressure in the tank; In higher flow, we find other methods,for example, wind velocity meter. In base of ideal gas equation, we calculate error between the flow of predicting and the flow measured by the wind-tunnel. Finally, we discuss the pressure difference in different point.