Experimental research on cyclone performance at high temperature

Abstract

To predict the influence of operating temperatures on cyclone performance, an experimental investigation was conducted on particle separation in a reverse flow, tangential volute-inlet cyclone separator with a diameter of 300 mm and with air heated up to 973 K. The test powder silica has a mass median diameter of 10 um, while inlet velocity range was 12–36 m/s. Both the separation efficiency and pressure drop of the cyclone were measured as a function of the inlet velocity and operating temperature. At the same inlet velocity, both the separation efficiency and pressure drop decrease with increasing temperature. In addition, optimum inlet velocity, at which the cyclone has its highest separation efficiency, tends to increase with a rise in temperature. An analysis on our own data and published results has shown that the fractional efficiency of a cyclone is a definite function of dimensionless numbers such as the Stokes number, the Reynolds number, the Froude number, dimensionless cyclone inlet area, and dimensionless outlet diameter. A nondimensional experimental correlation of the cyclone performance, including the influence of temperature, was obtained on the basis of our own previous work. The prediction of the influence of temperature on separation efficiencies and pressure drops is in fairly good agreement with experimental results.