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1. (WO2018015091) METHOD FOR DETERMINING A FUEL MASS FLOW AND FOR CONTROLLING THE INJECTION

Pub. No.:    WO/2018/015091    International Application No.:    PCT/EP2017/065158
Publication Date: Fri Jan 26 00:59:59 CET 2018 International Filing Date: Thu Jun 22 01:59:59 CEST 2017
IPC: F02D 41/00
F02D 41/30
F02D 19/02
Applicants: ROBERT BOSCH GMBH
Inventors: NAFE, Joerg
FALKENAU, Tobias
Title: METHOD FOR DETERMINING A FUEL MASS FLOW AND FOR CONTROLLING THE INJECTION
Abstract:
Method (100) for determining the mass flow Q of fuel (2) through an open injector (1, la-lf), comprising the determination of the pressure p (110) and of the temperature T (120) of the fuel (2) at at least one measuring location (31) in the feed line (3, 3a-3f) to the injector (la-lf) and the evaluation (150) of the mass flow Q as proportional to the pressure p and inversely proportional to the root of the temperature T, wherein the pressure p is corrected (140) to the pressure p' by the pressure drop Δρ which occurs when the injector opens in the feed line (3, 3a-3f) between the measuring location (31) and the injector (la-lf), wherein the mass flow Q, the length L, L1-L6, the diameter D, DR, D1-D6, the Darcy friction factor λ, and/or the pressure loss coefficient ζ, the feed line (3, 3a-3f) between the measuring location (31) and the injector (1a-1f) are taken into account during the determination (130) of Δρ. Method (200) for controlling the injection of fuel (2) in an engine (10) having a plurality of injectors (1a-1f) and a feed line (3, 3a-3f) leading to the injectors (la-lf) which comprises a common distributor rail (32) for the fuel (2), wherein the opening period of each injector (la-lf) is determined (210) from the setpoint injection mass M of fuel (2) and the mass flow Q of the injector (1a-1f) in the open state, wherein the mass flow Q is determined (100) individually for each of the injectors (1a-1f) in the open state according to the invention. Control unit (300) and computer program product.