Engine Commissioning and Setup for Steady State Test.

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CHAPTER 3: RESEARCH METHODOLOGY 3.0 Introduction

The details of the engine commissioning and experimental procedures for the steady state tests are given in this chapter. This includes the engine, exhaust and analysers’ preparation, the technical aspect, measurement and calibration of the equipment. The urea SCR spray system and the ammonia gas injection system will also be covered along with the calibration charts required. Several precautions and cleaning procedure will also be included especially for the urea SCR spray system. The final assembly of the SCR exhaust system will be covered and also the final experimental matrix for measuring the exhaust gases upstream and downstream of the SCR brick.

3.1 Engine Commissioning and Setup

The original plan was to use a Ford 4FM series diesel engine with a new transient engine test bed. Some time was spent to commission this engine with a new transient engine dynamometer within the university. Due to various problems with commissioning the 4FM series involving ECU Engine Control Unit, wiring harness and diesel injectors, a 2FM series diesel engine used during recent Lean NOx Trap LNT studies was configured to run steady state tests for this investigation on a EC Eddy Current dynamometer

3.1.1 Engine Commissioning and Setup for Steady State Test.

The recent Lean NOx Trap project within AEARG Automotive Engineering Applied Research Group Coventry University used a 2FM series diesel engine equipped with VGT and EGR, an Injection Control Unit ICU and an Engine Control Unit ECU. This engine is also equipped with common rail injection system with a high pressure fuel pump, an intercooler and an engine management system EMS programmed though dSPACE, GREDI and a throttle body to control the intake air to the engine. The throttle body was controlled by dSPACE using a customized application based on Matlab Simulink. The application software was capable of controlling the timing for main, pilot and post injection and also controlling the opening and closing of the throttle body. GREDI was the monitoring software which reads the ECU and displays the value of parameters needed on a host computer. Any parameter changed through dSPACE was recorded in GREDI alongside with the Froude Consine test bed host computer. All the software and hardware was supplied by Ford 26 including the license for dSPACE, GREDI and Matlab Simulink. At a later stage of this project the EMS capability from dSPACE and GREDI was disabled due to technical failure of the ECU. Another ECU was programmed for this 2FM series diesel engine and the previous control of the throttle body for regeneration purpose was disabled. Therefore this project focussed only on steady state testing using pre-programmed engine settings. The exhaust back pressure was also monitored as an indicator for the DPF cleaning process. The 2FM configuration is shown in figure 3.1.1 Figure 3.1.1 The 2FM Series Engine with Injection Control Unit ICU and Engine Control Unit ECU on Froude Consine AG150 engine dynamometer. The specification of the diesel engines is shown in table 3.1.1 and the power curve for this engine is supplied in the appendix 3.1.1 Table 3.1.1 Diesel Engine specification used for investigation Ford 2FM series Items Description Engine capacity 1998 cc 121.9 cu in Bore 86.0 mm 3.39 in Stroke 86.0 mm 3.39 in Compression ratio 18.2:1 Number of cylinders Inline 4, 16 valves Firing order 1-3-4-2 Rated power output 96.9 kW 130.0 bhp at 3800 rpm Rated torque 330 Nm 243.4 ft lbs at 1800 rpm Ignition type Common rail, diesel fuelled, direct injection system ICU ECU 27

3.1.2 Engine Dynamometer