Device for measuring the injection rate, method for producing a device of said type, and measuring method

Abstract

A device () for measuring the injection rate dm(t)/dt of an injection valve () for a fluid (), wherein m(t) is the injection quantity of the fluid () as a function of the time (t), having a measurement volume () which is closed off on all sides and which is filled with a test fluid (), having an opening () in one wall () of the measurement volume () for the purposes of receiving the injection valve () such that the injection valve (), in the installed position, projects with at least one injection opening () into the measurement volume (), and having a pressure sensor () which is arranged in the measurement volume (), wherein correction means () are provided for determining the propagation time of a pressure wave (), which originates from the injection opening () and which propagates through the test fluid (), to the pressure sensor () and for correcting the measured injection rate dm(t)/dt, taking said propagation time into consideration, to give a rectified injection rate dm'(t)/dt. A method for producing the device (), wherein the characteristic map () is determined by way of a fluid-dynamic simulation of the time-dependent and position-dependent local speed of sound c(t,x) in a partial volume of the measurement volume () which encompasses at least the path () from the injection opening () to the pressure sensor (), which simulation is based on at least one time-dependent boundary condition for the pressure (p) in the measurement volume () and/or for the injection quantity (dm). A method for measuring the injection rate dm(t)/dt of an injection valve () for a fluid ().