Improving the performance of micro pumps by reduction of flow pulsation for drug delivery application

Piezo-electrical diaphragm type mechanical micro pump (PZT micro pump) is one of the Micro Electro Mechanical System (MEMS) device dominant among all micro pumps because of its simple structure and low power consumption. PZT micro pump is widely used for drug-delivery systems basically-injection of glucose to diabetic patients and blood transportation, and also in other areas such as bioengineering, fuel drop generator for automobile heaters, micro metering valves for fuel injection system, etc. Fluid flow from these micro pumps is in the form of small discrete volumes with flow pulsating. But in application such as drug delivery system it may be required to have a continuous fluid flow without any flow pulsation. Therefore to have an adaptability of these micro pumps for drug-delivery applications, problem of pulsating flow can be overcome by proper sequencing of these pumps. In the present paper, an attempt has been made to study the multiple PZT micro pumps operated in parallel connection with sequential switching in order to reduce the flow pulsation. The flow pulsations have been measured in terms of pressure pulsation and average flow rate and obtained results are presented systematically in the paper.