AC MHD Micropump

Integrating the above equation with respect to wt from wl = 0 to 2n , we obtain 

The difference between the above equation and that of DC MHD equations is the factor cos (/ /2 in the last term on the left-hand side of the above equation. Hence, similar to the DC MHD case, we can write for AC MHD the average velocity and flow rate as 

The time average flow rate in AC MHD in the absence of the imposed pressure gradient is given by 

Maximum flow rate for AC MHD is observed when 0 = 0 and the maximum flow rate for AC MHD is 

Comparing the above equation with DC MHD (equation (7.75)), we see that the flow rate in DC MHD is twice that of AC MHD for the same current flow. However, AC MHD can operate at a higher current rating without the problem of electrolysis. 

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