Design and investigation of a high pressure micropump for dosing of high viscosity fluids

In recent years, the self-administration of drugs daily has become a standard medication regimen for diabetes and autoimmune disorders. This situation emphasizes the use of auto-injectors to facilitate administration, preferably at the patient’s home. So, this the sis introduces an alternative approach to the standard auto-injector design. The current medication tool will be improved by the use of a metal-based micro diaphragm pump developed by Fraunhofer EMFT with suitable design variations to dispense a precise volume of drugs in a given time frame.This thesis analyzes various designs of metal micropumps with piezoelectric actuators to dose high viscous fluids. Thus, the generation of high pressure becomes the optimiza tion goal. The possible design variations are introduced in the actuator design, such as the thickness of the metal foil, the thickness of the piezoceramic layer (disc-shaped bulkactuator and stack actuator), and the different diaphragm diameters. For viscous formu lations, different proportions of aqueous glycerine mixtures are used. As a first step, a comprehensive study is conducted to choose an optimal design solution through experi mental evaluations. For this, I designed a gravimetric test bench to investigate the effect of pump design alterations on generated flow rate and dosing time for different viscosi ties. In addition, further analyses of electrical actuation adaptions lead to performance optimization of the micropump. This work successfully shows the dosing capabilities of metal micropumps up to 25 mpas viscosity, and design variations show further potential for micropump optimization. Thus, incorporating micro-dosing technology to dispense precise amounts of drugs is proven to be one of the best solutions to meet the needs of the patients.