Proposal to establish a laboratory for combustion studies

Transcription

1 Proposal to establish a laboratory for combustion studies Jayr de Amorim Filho Brazilian Bioethanol Science and Technology Laboratory

2 SCRE Single Cylinder Research Engine Laboratory OUTLINE Requirements, Project Goals and Solutions Proposals Research tasks and technologies Single Cylinder Test bed and Engines Research tools for combustion studies with SCREs

3 Project Goals and Suggested Solutions PROJECT GOALS 1. Development of Spark Plugs project design ; effects on ignition, plasma and flame development 2. Investigation of deposits on spark plug and in the engine 3. Emission studies; e.g. NO, OH, HC, CH. 4. Cold start investigations 5. Direct injection spray and evaporation investigations (Injector Development)

4 Test bed system: SCE, SCTB and peripherals SCE: Air: NA Fuel: Ethanol - Gasoline interpretation ECU: open engine controller analyser analyser analyser Engine conditioning: data Diagnostic Optical Instrumen - tation controller Optical data access SCE shaft SCTB controller SCE data controller SCTB infrastructure: mechanical, media, energy, environment external coolant / lube oil supply at regulated temperature and pressure SCTB: compact test bed with active dyno, test bed controller Access to infrastructure: concrete base floor, cooling water, electric power supply, air in, exhaust out Peripherals, Diagnostics: to be defined to meet the needs

5 Project Application Matrix

6 SCRE Single Cylinder Research Engine Considerations for choosing the right components 1. What is the application target? 2. What engine configuration is required for this application? (fuel, injection and combustion type, naturally aspirated or charged, size, thermodynamic or optical engine) 3. What instrumentation and measurement devices are required for the desired application? (Imaging, thermodynamics, LIF, gas analysis etc.) 4. What test cell equipment is required for safe operation and measurement? (conditioning units, fuel measurement, blow by, air mass flow, temperatures and pressures ) 5. What special measurement systems are planned to be used, and what integration is required? (LIF, combustion analysis, emission ) 6. What are the requirements for the test cell and installation? 7. What trainings are required to operate the equipment safely and achieve the desired results?

7 SCRE Single Cylinder Research Engine OUTLINE Requirements, Project Goals and Solutions Proposals Research tasks and technologies to achieve them Introduction to Single Cylinder Test bed and Engines Research tools for combustion studies with SCREs

8 Spark Plug Development Goals Investigation of ignition behavior, temperatures and deposits Spark Plug Development Recommended Solutions Development of the spark plug requires operation under realistic conditions including high load and long term operation. For the investigations an optical access through endoscope with high resolution camera for flame investigation or infrared camera for surface temperature investigations can be used.

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10 Schematic of experimental setup

11 Peak Voltage (V) Peak Current (ma) Results Spark Plug Discharge Electrical Characterization 3,8 Electrical Parameters for Duty Cycle of 25 % ,6 3, ,2 3, ,8 2,6 2, , Duty Cycle (%)

12 Intensity (a.u.) Discharge temperature characterization The gas temperature was estimated from the rotational spectrum of the SPS of N 2 (C 3 Π u B 3 Π g ) using a comparison between the experimental spectra and the simulated ones. 1,0 Experimental Simulated 0,8 0,6 0,4 0,2 T rot =(2058 ± 75) K 0, Wavelength (A)

13 Electron density (cm -3 ) Intensity (a.u.) Electron density characterization Determined by Stark broadening on Hα emission line ,8x ,6x ,4x ,2x ,0x ,0x ,0x10 14 H, Duty Cycle 40% Ajuste Voigt Broadening Mechanisms Stark ressonante ne_d10% 11 0, n e [ nm ne_d15% ] ne_d20% P 119X h [ nm] T ne_d40% g van _ der _ Waals Natural Doppler 3,45PT g 0,7 2, [ nm] 4, T h [ nm] [ nm] -20 4,0x ,5 655,0 655,5 656,0 656,5 657,0 657,5 658,0 Wavelength (nm) Time (ms)

14 Electron temperature (K) Electron temperature characterization Determined by Saha equation using Argon emission lines ,1 475,0 476,9 478, Te D10% Te D15% Te D20% Te D40% Time(ms) 748,6 750,5 752,4 754,3

15 In-cylinder temperature evaluation Thermal imaging + calibration Direct view onto spark plug. Endoscope access from pent roof side Technical details: Fused silica window, endoscope with BK7 imaging optics, B/W camera, 10 ms exposure time in exhaust / intake stroke.

16 Objects: Spark plug or exhaust valves Thermocouple on sparkplug: radiation to temperature calibration Thermal imaging local sensitivity

17 Temp. [deg C] Thermal image. x local sensitivity field x calibration curve yields temperature field Window, endoscope and camera local sensitivity, use camera calibration device Thermal image On engine test bed Radiation intensity [rel. unit] Radiation to temperature conversion, use temperature calibration device Temperature field

18 18 In-cylinder thermal imaging: example on ignition timing effects

19 Flame and Plasma Spectroscopy & Imaging Goals Analysis of Flame and Plasma properties under real combustion conditions Recommended Solutions Flame and Plasma investigations require the best possible access to the spark plug and combustion chamber, and stable conditions for best repeatability and comparability. Therefore the recommended engine is a transparent SCRE with pent roof glass liner (full access to spark plug), piston with glass window and mirror unit (optical access from below) and port fuel injection (MPFI) for stable, homogeneous air-fuel mixture.

20 Transparent Engine: Example Flame Imaging Studies of interaction between injection, mixture formation and combustion with different optical technologies. High speed or high-resolution imaging through glass cylinder liner or piston window, mostly for studies of wall wetting and dispersed droplets leading to local sooting combustion. PLIF studies for investigation of non-reacting as well as reacting gas and liquid flows in a nonintrusive, instantaneous flow visualization with high spatial and temporal resolution.

21 Ethanol DI Cold Start Investigation Spray and Injector Analysis Goals Analysis and optimization of injection strategies for starting engines with Ethanol at low temperatures Recommended Solutions The critical point of engine starting in low temperature, especially with Ethanol is the evaporation of the fuel. To find the best timing and strategies for the injection, a SCRE with glass liner and high pressure direct injection system is required. Using imaging with high speed cameras, the injection spray and the resulting flame can be filmed. Since liquid fuel is burning with a much brighter flame, this technique clearly shows wall wetting and liquid fuel droplets, and can be used to analyse influences of injection parameters like timing, pressure or injector type on the starting process.

22 Transparent Engine: Example Spray Imaging Fuel pressure 4 bar Big droplets Fuel pressure 40 bar Small droplets Spray studies to investigate influences of injection timing, injection pressure and injection hardware. Using imaging technologies allows fuel droplet analysis. Using Laser Induced Fluorescense (LIF) allows fuel vapor distribution studies. Wall film Significantly reduced wall film The active dyno of the SCTB allows motoring the SCRE to conduct spray and vapor formation studies without combustion.

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24 SCRE Single Cylinder Research Engine Laboratory OUTLINE Requirements, Project Goals and Solutions Proposals Research tasks and technologies Single Cylinder Test bed and Engines Research tools for combustion studies with SCREs

25 Single Cylinder Compact Test Bed Specifications for single cylinder research engines test bed: Completely assembled with engine, active dyno, dyno control and conditioning systems for Engine Very low requirements for facility: - no special foundations or baseplates - only electrical and water supply needed The SCTB can be easily moved with a fork lift Flexible use with different engines, also multi cylinder up to 60kW/200Nm

26 Single Cylinder Engine and Test Bed Installation and key features Modular concept to combine the reliability of standard components with flexibility for specific solutions. Very low requirements for installation.

27 Transparent Research Engine with port fuel and direct injection systems SCRE with pent-roof glass liner and mirror system that allows optical access with cameras and other optical systems like Spectrometry systems or LIF: Flame and spray studies with high resolution or high speed cameras. Studies of injection parameter variation and optimization for reduced wall wetting and optimized mixture formation and combustion. Allows detailed studies of mixture formation and combustion with spectrometry, LIF or other techniques with full optical access to combustion chamber due to the pent-roof glass liner and piston window

28 Thermodynamic Research Engine with port fuel and direct injection systems SCRE spark ignited engine for combustion development and research also under high-load, high-speed and long-term operation. Combustion analysis by means of pressured based measurement (indicating) or endoscopic optical access to the combustion chamber. Surface temperature investigations on spark plug and valves with endoscope and infrared camera. High load and simulated turbo-charged operation. Emission trend analysis with FTIR and Online Soot Measurement. Long term operation possible for study of deposits and corrosion.

29 SCRE Single Cylinder Research Engine Laboratory OUTLINE Requirements, Project Goals and Solutions Proposals Research tasks and technologies to achieve them Introduction to Single Cylinder Test bed and Engines Research tools for combustion studies with SCREs

30 SESAM-FTIR R&D Emission Analyzer with Infrared Spectroscopy

31 Thermodynamic analysis of combustion: Indicating System and GCA Gas Exchange and Combustion Analysis

32 Fuel Consumption Measurement Fuel Measurement Systems and Sensors for SCRE

33 Conclusion Project management techniques required to build a modern test facility are the same as those for any multidisciplinary laboratory construction. New diagnostics need to be developed for contaminants detection in ethanol. Discharge phase parameters may be characterized using passive and active spectrocopies. Better understanding of combustion and pollutant formation processes in IC engines.