Analysis of the Metering Behavior and the Energy Efficiency of a Dosing Pump 2012-01-2039

Initially used in motor vehicles to convey a specific volume of fuel from a tank to the burner of an engine-independent heater, the range of applications for electro-magnetically driven dosing pumps has been widely expanded over the past few years, e.g. dosing pumps are part of the emission control system or used to convey a specific volume of fuel from a tank to the burner of an engine-independent heater. Whereas originally only conventional fuel was delivered, nowadays the dosing pumps have to be suitable for any kind of liquid media. As a result of the extensive fields of application, verification and improvement of the design for optimal usage and low energy consumption are needed. The paper presents experimental investigation and computer simulation of the dosing pump in order to examine its metering behavior and the energy consumption. Depending on the aim of the analysis, different simulation tools, namely computational fluid dynamics and system simulation with lumped parameters, are used.

With the help of computational fluid dynamics, which takes the piston motion and the fluid driven check valve into account, a profound understanding of the flow effects in the pump can be achieved. The aim of this work is to investigate the valve kinematics and the interactions with the surrounding fluid by analyzing the fluid-structure interaction. Comparisons are made by experimental testing. Measurements of the pressure inside the displacement volume as well as the valve dynamics are investigated. Noteworthy is a technique based on a laser Doppler vibrometer for examining the dynamics of the piston inside the fluid.

Because the importance of the energy efficiency is growing, this aspect requires further investigation. A system simulation model of the pump is built in order to be able to analyze the energy efficiency in more detail. A general study of the energy conversion process in the pump is presented. Besides mechanics and the hydraulic system, the model also contains a simplified form of the electromagnetic actuator. An energy flow diagram is used to quantify and illustrate energy transformation within the pump. The investigations show the fundamental energy consumer and are the basis for systematic technical improvement.