EXPERIMENTAL INVESTIGATION OF AN ION-DRAG PUMP-ASSISTED CAPILLARY LOOP

An ion-drag pump was constructed and calibrated to determine the available pumping pressure as a function of input voltage for various working fluids. The experimental results were then compared with an analytical model and found to predict the ion-drag pump performance to within +/-15%. Using this information, an analytical model capable of predicting the performance enhancement of an ion-drag pump-assisted capillary loop was also developed and compared with the values obtained from experimental tests conducted on a thermal test loop. Although the analytical model slightly overpredicted the performance enhancement resulting from the ion-drag pump, the predicted trends were similar to those obtained from the experimental program. These trends included decreased thermal test loop performance with increased evaporator/condenser elevation difference, increased performance (due to increased operating temperature), and an increase in performance ranging from 20 to 100%, due to the addition of a two-stage ion-drag pump. The performance enhancement of the thermal test loop was verified at various operating temperatures and evaporator/condenser elevation differences.