Diesel and Bio-Diesel Fuel Deposits on a Hot Surface

Transcription

1 Diesel and Bio-Diesel Fuel Deposits on a Hot Surface Masataka Arai and Yusmady Mohamed Arifin Energy System 3rd Laboratory Energy System Engineering Division Department of Mechanical System Engineering Graduate School of Engineering National University Corporation Gunma University Japan arai@me.gunma-u.ac.jp

2 Outlook of Future Engine System Gasoline Engine: High Fuel Economy and Zero Emission Engine for Hybrid Vehicle Performance: Super-charge (Variable TC), DI engine emission (Non-regulated Emission), Knocking (VVT) Emission: Fuel (Gasoline Syn. Fuel), Combustion (Burning-rate Control), Aftertreatment (TWC Multi-functional) Fuel Supply: Gas Engine (H 2 -Engine, CNG-Engine Fuel Resource, Infrastructure, Safety-use) Petroleum (Low-cost, Low-sulfur, High Octane-value), Bio-Fuel (Resource, Fuel-stability, Non-regulated Emission) Diesel Engine: Zero Emission and High Performance Engine Performance: Super-charge (Two-stage TC), LD-Diesel (Passenger Car), HD-Diesel ( High Power/Weight ratio) Emission: Fuel (Low-sulfur, Low-aromatic HC), Combustion (Spray Ultra-high-pressure Inj., Multi-stage Inj.) EGR(Electric Control), New Engine (HCCI, PCCI, LTC), Aftertreatment (NOx and PM Total Control) Fuel Supply: Petroleum (Low-cost, GTL), Bio-Diesel (Resource, Esterification, Fuel-stability, Non-regulated Emission) Passenger Car Emission Fuel Global Warming Total Energy Control Priority Cargo Truck CO 2 Increase of Population and Essential Commodities Dry-up of Petroleum New Energy Resource Change of Life Style Improvement of IC Engine Hybrid New Engine (Fuel Cell, etc.) Artificial Environment year Jan Masataka Arai, Gunma Univ.

3 Automobile Problem Automotive Vehicle and 3Es Tri-lemma Problem Fuel Energy Resource National Security Energy Economy Pay Load Living Substance Development of Society for Happy Life Contaminated Air HC, CO, SOx, NOx, PM Lead, Heavy Metal, etc Environment Greenhouse Gas CO 2

4 Background and Objectives of Fuel Deposits Research Bio-Diesel Fuel Alternative fuel for sustainable energy resource Alternative fuel for energy security Fuel Robustness Carbon neutral fuel for Greenhouse Problem Oxygenated fuel for PM reduction Low sulfur fuel for SOx, Sulfate, Poisoning of Aftertreatment System Applicability for Conventional Engine Fuel Stability Fuel Deposits caused by Non-distillated Fuel Objective of this study Evaluation of Fuel Deposits Formation Mechanism of Fuel Deposit

5 diesel fuel Fuel Properties Palm Oil Ester

6 Engine Test and Single Droplet Dripping Test Bio-diesel fuel potential Background Bio-diesel fuel effects in engine Substituted Diesel fuel Reduce Emission Main idea Not well known Fuel deposits Other effects Deposits mechanism Deposits formation factors Real engine Difficult Method Single droplet repetition apparatus

7 Method of Fuel Deposits Research Fundamental Test on a Hot Surface Repetition of fuel droplet dripping Fuel Droplet Repetition of Dripping Impinged Droplet Fuel Deposits Surface condition Temperature Formation process of deposits Hot Surface Engine Test Real deposits in a combustion chamber Plug for deposits evaluation Plug surface temperature is controlled by heater and thermocouple Effect of spray impingement Effect of combustion Effect of operating condition on engine Combustion chamber of D.I. diesel engine

8 Single Droplet Repetition Apparatus for Fuel Deposits Fuel Droplet Impinged Droplet Repetition of Dripping Hot Surface Fuel Deposits Multi-time repetition of fuel droplet dripping on a hot surface Droplet evaporation and fuel film oxidation Fuel deposits

9 Objectives of Single Droplet Dripping Test Objectives To investigate fuels deposition on Aluminum Alloy surface Amount of Deposits Accumulated Deposits Development Relationship Deposits Formation Factors

10 Single Droplet Repetition Apparatus Pinch cock Needle L h = 80 mm Infrared laser Fuel tank Detector Counting system Infrared thermometer DF: Diesel fuel JIS No.2 B100: Palm oil based ester bio-diesel fuel B20: 20% Bio-blended diesel fuel (20%B100+80%DF) Ф90 mm Fuel Deposits Hot surface plate Thermocouple 2 mm Single Droplet Evaporation Droplet lifetime Evaporation Characteristic Heater Temperature controller Deposits amount & Td Relationship To power supply Deposits Surface temp. Multi-droplets Deposition Lifetime estimation

11 Evaporation Characteristic on a Hot Surface Lifetime τ life s Diesel fuel Surface: Aluminum Alloy (JIS 2017S) M d = 4.7mg D d = 2.2mm L h = 80mm Evaporation state Single droplet Non-single droplet DF B100 B20 MEP Maximum evaporation point Indicated Temperature T i Indicated Temperature, T i Surface Temperature*, T S Lifetime τ life s Unit C C Bio-diesel fuel Surface: Aluminum Alloy (JIS 2017S) M d = 5.0mg D d = 2.2mm L h = 80mm Evaporation state Single droplet Non-single droplet Maximum evaporation point Indicated Temperature T i DF % Bio-blended diesel fuel Surface: Aluminum Alloy (JIS 2017S) M d = 5.4mg D d = 2.3mm L h = 80mm Evaporation state Single droplet Non-single droplet MEP MEP MEP B *Estimate by using Equation 1; T S = T i Lifetime τ life (s) Maximum evaporation point Indicated Temperature T i ( ) B

12 Dripping Interval and Overlap of Droplet Evaporation Fuel Droplet Repetition of Dripping Impinged Droplet Fuel Deposits Hot Surface

13 Effects of Dripping Interval and Surface Temperature Condition on Deposits Development Fuel B100 T i 370 C 370 C τ life 6s τ imp 5s 8s Initial condition Wet Dry Deposits development Rapid B C 2s 5s Dry Rapid and DF 320 C 15s 5s Wet 370 C 1s 3s Dry 5s Dry

14 Repetition Test of Bio-diesel Fuel Fuel B100 B20 DF T i τ life τ imp Initial Deposits condition development 370 C 6s 5s Wet Rapid 370 C 8s Dry 370 C 2s 5s Dry Rapid and 320 C 15s 5s Wet 370 C 1s 3s Dry 5s Dry

15 Logarithmical Expression of the Test Results and Empirical Equation of Deposits Formation M R = M D α N β D

16 Repetition of Fuel Dripping and Deposits Development Total Relative Deposition Mass MR/MD Bio-diesel fuel and its blend Surface: Aluminum Alloy (JIS 2017S) L h = 80mm Indicated temperature: 370 C B100, Impingement interval = 5±1 seconds B20, Impingement interval = 5±1 seconds B100, Impingement interval = 8±1 seconds M R /M D = N D A M R /M D = N D 1.1 B C M R /M D = N D 0.3 M R /M D = N D 0.7 Total Relative Deposition Mass MR/MD Diesel fuel Surface: Aluminum Alloy (JIS 2017S) L h = 80mm Indicated temperature: 370 C Impingement interval = 5±1 seconds Indicated temperature: 370 C Impingement interval = 3±1 seconds Indicated temperature: 320 C Impingement interval = 5±1 seconds D M R /M D = N D Number of Droplets N D B100 & B20 Coefficient α Amount of deposits at initial stage of deposition M R = M D α N β D Empirical Equation Number of Droplets N D DF Index β Rapid development β 1.0 development β<1.0

17 Logarithmical expression value for B100, B20 and DF Coefficient α Amount of deposits at initial stage of deposition M R = M D α N β D Empirical Equation Index β Rapid development β 1.0 development β<1.0

18 Deposits Development Fuel B100 B20 DF T i 370 C 370 C 370 C 320 C 370 C τ life 6s 2s 15s 1s Hot surface temperature Not the main contributor for rapid development τ imp 5s 8s 5s 5s 3s 5s Initial wet condition Initial condition Wet Dry Dry Wet Dry Dry Deposits development Rapid Rapid and Impingement interval Enhanced deposits accumulated

19 Properties of Test Fuels Unit DF B100 B20 C kg/m Distillation T90 C Final boiling point C 350 NA NA Sulfur content ppm <10 <5 26 Carbon residue (10% dist.) %mass NA Cetane index Glycerides (Mono-/Di Di-/Tri-) %mass NA *NA: not available Carbon residue Non-volatile matters Fuel components Non-volatile matters Fuel oxidation: Glycerides High molecular weight compound

20 Carbonaceous 0 10 mm Deposits Sample at N D =3, mm Carbonaceous A: B100,370 C,5s 0 10 mm Carbonaceous Total Relative Deposition Mass MR/MD Bio-diesel fuel and its blend Surface: Aluminum Alloy (JIS 2017S) L h = 80mm Indicated temperature: 370 C B100, Impingement interval = 5±1 seconds B20, Impingement interval = 5±1 seconds B100, Impingement interval = 8±1 seconds M R/M D = N D A M R/M D = N D 1.1 B M R/M D = N D 0.3 M R/M D = N D B C Total Relative Deposition Mass MR/MD Diesel fuel Surface: Aluminum Alloy (JIS 2017S) L h = 80mm Indicated temperature: 370 C Impingement interval = 5±1 seconds Indicated temperature: 370 C Impingement interval = 3±1 seconds Indicated temperature: 320 C Impingement interval = 5±1 seconds D M R /M D = N D C: B100,370 C,8s 0 10 mm White ash Number of Droplets N D B100 & B20 Number of Droplets N D DF B: B20,370 C,5s Porous structure Lower thermal conductivity Higher thermal conductivity Deposits physical properties Carbonaceous with brown-black color D: DF,370 C,5s More compact structure Altered droplet lifetime

21 Deposits Surface Temperature 1/2 Deposits Surface Temperature Td C Indicated temperature Droplet lifetime estimation at maximum T d Bio-diesel fuel Surface: Aluminum Alloy (JIS 2017S) L h = 80mm Indicated temperature = 370 C Impingement interval = 5±1 seconds Max. Deposits temperature Min. Deposits temperature Number of Droplets N D Surface temperature fluctuation region Overlapping Non-overlapping Impingement interval Droplet Lifetime τ life s Deposits Surface Temperature Td C Indicated temperature 20% Bio-blended diesel fuel Surface: Aluminum Alloy (JIS 2017S) L h = 80mm Indicated temperature = 370 C Impingement interval = 5±1 seconds Max. Deposits temperature Min. Deposits temperature Surface temperature fluctuation region 305 Droplet lifetime estimation at maximum T d 40 Overlapping Non-overlapping Impingement 20 interval Number of Droplets N D Droplet Lifetime τ life s B100,370 C,5s B20,370 C,5s

22 Deposits Surface Temperature 2/2 Deposits Surface Temperature Td C Indicated temperature Droplet lifetime estimation at maximum T d Surface temperature fluctuation region Bio-diesel fuel Surface: Aluminum Alloy (JIS 2017S) L h = 80mm Indicated temperature = 370 C Impingement interval = 8±1 seconds Max. Deposits temperature Min. Deposits temperature Impingement interval Deposits Surface Temperature Td C Number of Droplets N D B100,370 C,8s Overlapping Non-overlapping Droplet Lifetime τ life s Indicated temperature Droplet lifetime estimation at maximum T d Diesel fuel Surface: Aluminum Alloy (JIS 2017S) L h = 80mm Indicated temperature = 320 C Impingement interval = 5±1 seconds Max. Deposits temperature Min. Deposits temperature Impingement interval Number of Droplets N D Deposits Surface Temperature Td C Surface temperature fluctuation region Overlapping Non-overlapping DF,320 C,5s Droplet Lifetime τ life s Indicated temperature Droplet lifetime estimation at maximum T d Surface temperature fluctuation region Diesel fuel Surface: Aluminum Alloy (JIS 2017S) L h = 80mm Indicated temperature = 370 C Impingement interval = 5±1 seconds Max. Deposits temperature Min. Deposits temperature Number of Droplets N D Overlapping Non-overlapping Impingement interval DF,370 C,5s Droplet Lifetime τ life s

23 Deposits surface temperature fluctuation Cooling effect A surface oxidation B Heat transfer C A B C A B Rapid development development Cooling effect Greater effect surface oxidation Heat transfer Td ΔTd Td ΔTd Td ΔTd

24 Formation Mechanism of Fuel Deposits Wet Condition No Big Impact on Rapid Development Overall Conclusions Enhanced Total Amount of Deposits Amount of Deposits B100, B20> DF Deposition Factors Impingement interval Hot surface temperature Fuel types Physical structure of deposits

25 Conclusions In this study, the results are summarized as follows; Overlapping of droplet evaporation lifetime and porous features of deposits are significant in producing wet condition. However, the wet condition did not give big impact on rapid development of deposits, but it enhanced total amount of deposits accumulated on hot surface. Bio-diesel fuel and bio-blended blended diesel fuel produce more deposits comparing with diesel fuel. Deposits development of Bio-blended diesel fuel showed combination behavior of bio- diesel fuel and diesel fuel. The factors that effect the fuel deposition are impingement interval, hot surface temperature, fuel type, and physical structure of deposits.

26 Engine Test Equipment (Fuel Deposits Test) Energy System 3rd Laboratory, Gunma Univ. Plug for deposits evaluation Plug surface temperature is controlled by heater and thermocouple Combustion chamber of D.I. diesel engine

27 Deposition Test Plug Thermocouple Thermocouple Support pipe Plug Heater Injector Cylinder head Heater Thermocouple Copper packing Cylinder Diesel spray Piston Thermocouple Intake port Combustion chamber area 6 mm 2 mm Diesel spray Injector φ12 mm Plug Exhaust port

28 Engine Test for Fuel Deposits Research Real engine test Positive Relation ship? Negative Fuel design Engine design Reason? Find another way

29 Fuel Deposit on a Cylinder Head Deposition mass per unit area mg/cm Ne = 1200 rpm θ inj = 15deg. BTDC λ = 2.4 Diesel Fuel + 1%oil 1 10 Time h T c = 240 Diesel Fuel Rate of PM components % Ne = 1200 rpm θ inj = 15deg. BTDC λ = Diesel fuel :SULFATE :SOOT :SOF :ASH Diesel fuel+1 %oil Total mass of deposit for diesel fuel and diesel fuel blended with 1% engine oil PM composition

30 Fuel Deposition Test (2) Deposition mass per unit area mg/cm Ne = 1200 rpm θ inj = 15deg. BTDC λ = 2.4 Diesel Fuel + 3%oil T c = 240 Diesel Fuel + 1%oil Diesel Fuel Time h Tentative Conclusion Positive Correlation between Deposits of Droplet Dripping Test and Engine Deposits

31 The End Thank you for your attention