Nghiên cứu sử dụng nhiên liệu sinh học butanol trên động cơ đánh lửa cưỡng bức tt tiếng anh

-1MINISTRY OF EDUCATION AND TRAINING THE UNIVERSITY OF DANANG HUYNH TAN TIEN A STUDY ON THE USE OF BUTANOL BIOFUEL ON SPARK-IGNITION ENGINES MAJOR: AUTOMOTIVE ENGINEERING CODE: 62.52.01.16 SUMMARY OF DOCTORAL THESIS DANANG – 2019 -2The thesis is completed at: THE UNIVERSITY OF DANANG Science facilitator: Prof Dr Tran Van Nam Assoc Prof Dr Duong Viet Dung Reviewer 1: …………………………………………………… Reviewer 2: …………………………………………………… Reviewer 3: …………………………………………………… The thesis will be protected in front of the thesis review committee at the University of Danang At: …………………………………………………………… Can find thesis at: - Vietnam National Library - Information - Learning Resource Center, The University of Danang -1INTRODUCTION Energy is a big concerns in our modern world for the last few decades as it is significantly influenced by the pollutant emissions generated from the combustion of fossil fuels Consequently, the automotive industry investigators turn their attention to the alcohol as an alternative fuel in an internal combustion engine for the purposes of reducing the carbon-based fossil fuels (e.g., CO2) and protecting the depletion of oil reserves Nowadays, combined gasoline and bio-butanol, which is made from petroleum, can be used as an alternative fuel for SI engines However, the chemical and physical properties of gasoline and butanol are different, so that the combustion process of the gasoline-butanol mixture is different with that of pure gasoline To contribute to the diversification of clean fuels used for combustion engines, improving the efficiency of engines using gasolinebutanol fuel mixture is reasonable and worth to study due to the depletion of oil reserves In Vietnam, there is no study on modeling the combustion process of spark-ignition engine fueled by gasoline-butanol Therefore, the choosen topic “A study on the use of butanol biofuel on spark-ignition engines” is very scientific and practical significance Objectives of the study This study focuses on evaluating the properties of biofuel with diffirent concentrations of butanol in blends and the effects of biofuel on performance and emissions of a traditional gasoline engine In addition, the study some of the process parameters of biofuels on traditional gasoline engines; provides technical direction, proposes solutions for improving and adjusting the engine The engine was fueled with different gasoline-butanol blends The gasoline-butanol blends were Bu0, Bu10, Bu15, Bu20, Bu25, Bu30, Bu40, and Bu50, indicating the content of butanol in different volume ratios (e.g., Bu10 contains 10% butanol and 90% gasoline in volume) -22 Object and scope of the study A 4-cylinder, 16-valve, 1.6-L spark-ignition DAEWOO engine, model A16DMS with a compression ratio of 9.5 was used to perform experiments To examine the effects of using gasoline-butanol blends on the engine performance and emission characteristics, there is no modification made for the test engine The thesis presents the characteristics of engine performance and emission on SI engines using biofuels, i.e., Bu10, Bu15, Bu20, Bu25, Bu30, Bu40, and Bu50, and performs simulations using a numerical software (ANSYS FLUENT Simulation) Research Methods The methodologies used in this study include experimental setup, numerical modeling, empirical and analytical, and evaluation The experimental setup was conducted on an engine testing systyem (AVL Laboratory) on injection, evaporation, mixing, economic, performance, and emissions characteristics of engine Scientific and practical significance * Scientific significance: Doing research on a new biofuel has many advantages, e.g., minimizing environmental pollution, mixing with gasoline in a large proportion, reducing fuel costs, and reducing pressure on the use of gasoline This study examines the use of different blends on a spark-ignition engine using numerical and experimental models It is recommended to use the bio-butanol without the conversion of conventional gasoline engines * Practical implication: The thesis has evaluated the performance (i.e., economic and technical problems) and emissions of spark-ignition engine using biofuels Bu10, Bu15, Bu20, Bu25, Bu30, Bu40, and Bu50 Consequently, it provides the recommendation and technical solutions for the -3engine when using gasoline-butanol blends with the butanol concentration is up to 50% New finding of the thesis - Experimental results confirm that it is possible to use gasolinebutanol with the ratio upto Bu30 at the load and the speed at which the regular engine work is about 30% to 70% of the throttle opening for an engine speed ranged from 1250 rpm to 4250 rpm This will not affect the engine's economic performance compared to that of gasoline (i.e., Bu0) - The results present the fuel samples of the gasoline-butanol mixture using on spark-ignition engine and the simulation results of the spraying of gasoline-butanol mixtures on the 1-side port intake It is confirmed that butanol mixed with gasoline will be able to evaporate butanol by the solubility of butanol in gasoline and it is almost complete Separated injection of gasoline or butanol will raise the equivalence ratio of the mixture before igniting This is because at this time the gasoline is completely evaporated but butanol will not be completed, so it tends to stratifie butanol in the mixture This stratification is not conducive for the combustion process as the butanol is not conducive to anti-knock to the engine's combustion Content of thesis (1) Numerical modeling of injection fuel and mixing (2) Examine expetimentally the effects of injection gasoline-butanol on combustion process and emissions of dual-fuel engine gasoline-butanol (3) Examine expetimentally the performance and pollutant emissions of dualfuel engine gasoline-butanol (4) Examine numerically the performance and emissions characteristics of ducal-fuel engine gasoline-butanol -4The thesis consists of chapters: Chapter 1: Overview, Chapter 2: Theoretical research, Chapter 3: Experimental research, Chapter 4: Conclusions and Discussion Chapter OVERVIEW 1.1 General 1.1.1 Vehicles and environmental pollution The Prime Minister of Vietnam has just signed Decision No 985a on the issuance of the National Action Plan on air quality management targets by 2020 and the vision by 2030 Under this decision, cars and motorbikes are suggested to use biofuel 1.1.2 Alternative fuels used on vehicles Alcohol (i.e., butanol and propanol) derived from plants can be used as a substitute fuel for fossil fuels Butanol has the same properties as gasoline and is considered as an alternative fuel since it can be produced from sugar fermentation 1.1.3 The use of biofuels Currently, there are about 50 countries in the world exploit and use biofuels Biofuels are used including clean vegetable oils, butanol, biodiesel, dimethyl ether, ethyl tertiary butyl ether, and their derived products The Prime Minister approved the "Scheme on development of biofuels up to 2015, vision 2025" According to the Decision No 53/2012 / QD-TTg November 22, 2012 on the promulgation of a roadmap for the application of using bio-fuel blend ratios December 1, 2014, the commercial product of E5 was released and it was used in some big cities and since December 1, 2015 1.1.4 Use of bio-butanol fuel on internal combustion engine Research on the use of biofuels on internal combustion engines is attracted many research centers as well as researchers -5Vietnam has done some research on the use of bio-butanol as a fuel for internal combustion engines It has proven that bio-ethanol can be used as a potential alternative Butanol has higher heating value than ethanol, but it provides more stable due to its less hydration 1.2 The need to improve fuel systems on spark-ignition engines 1.2.1 The development history of the fuel supply system on sparkignition engines 1.2.2 Improving the fuel system of spark-ignition engine by reducing fuel consumption and environmental pollutions The GDI engine overcomes the simple disadvantages of a PFI engine, especially regarding related wet the wall of port intake The fuel membrane on the intake port of the PFI engine acts as an integrated capacitor Therefore, the amount of fuel is measured incorrectly due to the liquid fuel content inside the membrane, not from the current measured fuel by injectors The direct injection of fuel into the cylinder of the four-stroke spark ignition engine eliminates the integrated fuel membrane on the intake wall Direct injection of gasoline with little or no rich of a mixture, therefore cold start can start on the second cycle and can significantly reduce HC during load change 1.3 Characteristics of combustion processes in spark-ignition engines using gasoline-butanol 1.3.1 Evaluate bio-butanol fuel effect on economic and technical features on internal combustion engine 1.3.2 Evaluate bio-butanol fuel effect on internal combustion engine to flame spread process Chapter THEORETICAL RESEARCH 2.1 Properties of fuel used on spark ignition engines 2.1.1 Introduction to bio-butanol 2.1.2 Physicochemical properties of butanol fuel -62.1.3 Evaluate indicators of gasoline and butanol 2.2 Theory of fuel injection on a spark-ignition engine 2.2.1 Port injection gasoline system 2.2.2 Direct injection gasoline system 2.3 Theoretical simulation process of fuel injection on a spark-ignition engine 2.3.1 Convection-diffusion equations 1) Continuity of mass    dV = − S  udS t V (2.2) 2) Conservation of momentum   udV = − S (u.dS )u − S pdS + V Fbody dV + Fsurf t V (2.4) 3) Energy conservation Dh Dp = +   (kT ) +  Dt Dt  (2.6) 2.3.2 System of equations of turbulent flow   + ( ui ) = t xi   p  (  ui ) + (  uiu j ) = − + t x j xi x j +  −  uiuj x j (   u u j u   −  ij l      i +   x j xi xl   ) (2.9) (2.10) The above equations are called the Navier-Stokes average Reynolds equations (RANS) 2.2.3 Equation description for spray jet (( ))  ( )   +  U −U  = k bk t x x k k     kk   + S   x   k  (2.11) The heat exchange and substance in the evaporation process of the particle is modeled by Dukowicz model: -7md c pd • dTd dm = L d +Q dt dt (2.20) 2.3.4 Theory of droplet fuel evaporation a) Metabolism by diffusion control model mp (t + t ) = mp (t ) − Ni Ap M w,i t (2.36) b) Determination of vapor pressure and diffusion coefficient Tf = Tp (T − Tp ) (2.39) c) Determination of boiling point and evaporation heat Tbp h fg = −  c p , g dT + h fg ,bp (2.41) Tp d) Heat exchange between air and fuel droplets mp c p dTp dt = hAp (T − Tp ) − dm p dt h fg + Ap p ( R − Tp ) (2.42) 2.4 ANSYS Fluent simulates the spraying process Flows in and out of the cylinder are modeled using the RANS model Sprays are modeled by the Decay Drop Model (DPM) based on the Eulerian - Lagrangian method Controlled diffusion / diffusion modeling has been used to model the evaporation of butanol and gasoline and provides a combustion model with the amount of steam fuel for each fuel 2.4.1 Set up the fuel injection process In addition, to solve the transport equation for continuous phase, ANSYS Fluent allows simulation of a discrete second phase in a Lagrange reference frame This second phase consists of spherical particles, which can be captured to represent drops or bubbles, dispersed in continuous phase ANSYS Fluent computes the trajectories of discrete phase entitled in the discrete phase model -8- b) c) a) Figure 2.1: Injection gasoline-butanol model 2.4.1.1 Selected Discrete phase conditions 2.4.1.2 Rosin-Rammler diameter distribution method 2.4.1.3 Spray jet decay model ANSYS Fluent provides two models of spray decay: The Taylor Analogy Breakup (TAB) model and the "wave" model 2.4.2 Geometric model 2.4.3 Initial conditions and boundary conditions The basic properties of gasoline and butanol are incorporated into ANSYS Fluent At the same time, the physical parameters of the intake and exhaust gas are entered in ANSYS Fluent Chapter EXPERIMENTAL RESEARCH 3.1 Purpose and empirical objects 3.1.1 Experimental objectives The experimental setup was conducted to estimate the effects of using different butanol rates (i.e., Bu10, Bu20, Bu30, Bu40, and Bu50) on -113.4 Experimental results 3.4.1 Fuel properties analysis 3.4.2 Evaluating the materials 3.4.3 Measured power Chapter RESULTS AND DISCUSSION 4.1 Experimental results 4.1.1 Brake torque and power output The results show that there is a decrease in brake torque and power output when using gasoline-butanol pre-blended compared to gasoline RON92 - At 10%THA with engine speed ranged from 1250-2500 rpm, brake torque decreased by an average of 3.5%, 6.6%, 10.7%, 13.9%, and 20.8% in turn when comparing Bu10, Bu20, Bu30, Bu40, and Bu50 with Bu0 - At 30% THA with engine speed ranged from 1250 to 3500 rpm, brake torques when using Bu10 and Bu20 are almost equal to Bu0 Especially, at engine speed is above 2000 rpm, in the case of Bu10, the brake torque slightly higher than Bu0, while this of Bu20 is slightly less than Bu0 For the case of Bu30, Bu40, and Bu50, the brake torque is smaller than the average of 2%, 5% and 7%, respectively, compared to that of Bu0 - At 50%THA with engine speed ranged from 1250-4250 rpm, the brake torque decreases by an average of about 1%, 3%, 5%, 6.4%, and 7.9%when compared Bu10, Bu20, Bu30, Bu40, and Bu50 to that of Bu0, respectively In which, the brake torque’s reduction level is remained at a speed below 3000 rpm When the engine speed is higher than 3000 rpm, as using Bu10, the brake torque is larger than that of Bu0 - At 70%THA with engine speed ranged from 1250-4250 rpm, the brake torque decreases by an average of 1.3%; 3.1%; 5.5%; 8.8% and 13.2% when compared Bu10, Bu20, Bu30, Bu40, Bu50 to that of Bu0, respectively In this -12load condition, only when using Bu10 and at speed above 3000 rpm, the brake Me (Nm) torque value is similar to that of Bu0 90 80 70 1250 1500 1750 2000 2250 2500 2750 3000 3250 3500 n (rpm) Bu0 Bu10 Bu20 Bu30 Bu40 Bu50 Figure 4.1: Brake torque (Me) at 10%THA Me (Nm) 70 60 50 40 30 1250 Bu0 1500 1750 Bu10 Bu20 2000 n (rpm) Bu30 2250 Bu40 2500 Bu50 Figure 4.2: Brake torque (Me) at 30%THA Me (Nm) 120 110 100 90 80 70 1250 Bu0 1750 Bu10 2250 Bu20 2750 3250 n (rpm) Bu30 3750 Bu40 Figure 4.3: Brake torque (Me) at 50%THA 4250 Bu50 -13- Me (Nm) 130 120 110 100 90 80 1250 Bu0 1750 2250 Bu10 Bu20 2750 n (rpm) 3250 Bu30 3750 Bu40 4250 Bu50 Figure 4.4: Brake torque (Me) at 70%THA 4.1.2 Specific fuel consumption Specific fuel consumption (ge) tends to increase and the specific energy consumption (qe) tends to decrease when increasing the ratio of butanol in the blends Depending on the load and engine speed, the specific consumption fuel has the notes as following: - At a load level corresponding to 10% THA, the specific fuel consumption, for the engine speed ranged from 1250-2500 rpm, increases the average value of approximately -2, 7, 10, 19, and 22% when compared Bu10, B20, B30, Bu40, and Bu50 to that of Bu0, respectively - At a load level corresponding to 30% THA, the specific fuel consumption, for the engine speed ranged from 1250-3500 rpm, increases an average value of approximately -1, 2, 4, and 7% when compared Bu10, B20, B30, Bu40, and Bu50 to that of Bu0, respectively - At a load level corresponding to 50%THA, the specific fuel consumption, for the engine speed ranged from1250-4250 rpm increases an average of 0, 2, 3, 7, and 9% when compared Bu10, B20, B30, Bu40, and Bu50 to that of Bu0, respectively - At the load level corresponding to 70% BG, the specific fuel consumption, for the engine speed ranged from 1250-4250 rpm increases an -14average value of approximately 1, 1, 3, 5, and 7% when comparing Bu10, B20, B30, Bu40, and Bu50 to that of Bu0, respectively Because butanol has a calorific value of 1.3 times lower than gasoline, the specific energy consumption decreases by about 13% when mixed 10% of butanol into gasoline under the same conditions As a result, except for 10% THA, the throttle position level remains the power consumption of the engine as using the Bu10, Bu20, Bu30, Bu40, and Bu50 are all lower than that of Bu0 a) 10%THA 450 c) 50%THA 425 400 ge (g/kWh) ge (g/kWh) 400 350 300 375 350 325 300 275 250 1250 1500 1750 2000 2250 2500 n (rpm) Bu0 Bu30 Bu10 Bu40 1250175022502750325037504250 n (rpm) Bu20 Bu50 Bu0 Bu30 b) 30%THA 425 400 ge (g/kWh) ge (g/kWh) Bu20 Bu50 d) 70%THA 425 400 Bu10 Bu40 375 350 325 375 350 325 300 275 1250 300 1750 Bu0 Bu30 2250 2750 n (rpm) Bu10 Bu40 3250 Bu20 Bu50 1250175022502750325037504250 n (rpm) Bu0 Bu30 Figure 4.5: The specific fuel consumption (ge) of engine Bu10 Bu40 Bu20 Bu50 -154.1.3 Pollution emissions CO and HC emissions decrease in proportion to butanol in the blends due to a combustion process rather than when using pure gasoline The concentration (%) of CO at levels of speed: 1250, 2250, 3250, and 4250 rpm shows that, when butanol added to gasoline, CO concentration is decreased At 3250 rpm, CO is reduced by 10-15% when adding 10% butanol At speeds of 2250 and 4250 rpm, CO reduction rate is about 4-6%, especially at the speed of 1250 rpm, the reduction rate is only about 2-3% Slightly different from CO emissions, HC levels only decreases at Bu10 to Bu30, then increases again When the engine speed is at 3250 and 4250 rpm and using Bu10 to Bu30, the emissions have a significant reduction in HC by 30% (as adding 10% butanol to gasoline) When using Bu40 and Bu50, HC emissions tend to increase again At the engine speed of 2250 rpm, HC emission only decreases about 10% And at the engine speed of 1250 rpm, HC emissions decreases insignificantly about 5% Consequently, when butanol mixed with gasoline at high rates (e.g., Bu40 and Bu50), CO and HC emissions tend to increase again compared to that of Bu20 This is because with a large amount of butanol, the evaporate rate of blend is low, so that the fuel does not have a chance to burn off At the same time, low engine speed, low air flow velocity makes heterogeneous CO (%) HC (ppm) mixture; therefore, leading to increment HC and CO emissions 200 100 0 10 1250 20 30 40 Butanol (%) 2250 3250 50 4250 1250 10 20 30 Butanol (%) 2250 Figure 4.18: Emissions of CO and HC 3250 40 50 4250 -16CO2 emissions tend to increase slightly at Bu10 but decrease when increasing the ratio of butanol in blends, among about 2.5% if adding 10% butanol into gasoline When increasing the ratio of butanol, it reduces the carbon content in the fuel, this is the main reason for the mixture of Bu20 and Bu30 has CO2 emission decreases compared to that of Bu0 and Bu10 In addition, Bu40 and Bu50 are also affected by incomplete combustion, such as CO and HC NOx emissions when using gasoline-butanol blends are significantly increased at a high speed (i.e., 4250 rpm) corresponding to the Bu10, Bu20, and Bu30 ratios (the increment of nearly 42%) At engine speed lower than 3250 rpm, the increase of NOx for the Bu10, Bu20, and Bu30 is still around 8% At engine speeds lower than 2250 rpm, for the Bu10, Bu20, and Bu30, NOx is still around 5% At the lowest speed of 1250 rpm, NOx only slightly increases in the Bu10 From Bu20, it decreases by about 5% when adding 10% butanol to gasoline 15 CO2 (%) NOx (ppm) 2500 14 13 2000 1500 1000 500 0 10 20 30 40 50 1250 Butanol (%) 2250 3250 4250 1250 10 20 30 40 50 Butanol (%) 2250 3250 4250 a) b) Figure 4.19: Emissions of CO2 and NOx 4.2 Results of simulation of gasoline-butanol fuel injection process Simulation mode is selected for full throttle opening, within the speed ranged from 2000 to 4500 rpm The fuel used in the simulation is combined from two single fuel fuels: gasoline (C8H18) and butanol (C4H10O) When -17spraying the mixture, butanol and gasoline are pre-blended together, the dynamic properties of the mixture are determined by the mixed expressions based on the properties of the component fuels When separately sprayed with pure gasoline, the ratio of butanol is set to zero and vice versa 4.2.1 Comparison of evaporation of butanol compared to gasoline Unlike gasoline, butanol has not evaporated immediately after spraying, but only occurs when the spray is propagated inside the cylinder where the pressure is low The evaporation of butanol mainly occurs during charging, at the beginning of the compression process and almost does not evaporate at the end of the compression process This is because the saturated evaporation pressure of butanol is about times lower and the latent heat is slightly higher about times than those of pure gasoline Therefore, the concentration of butanol vapor obtained at the end of the compression process is smaller than that of pure gasoline Butanol has not been evaporated totally after injecting; therefore, the mixture is less homogeneous than the pure Density of fuel (Fv) Evaporation rate gasoline Figure 4.20: Comparison of evaporation rate, in-cylinder pressure, temperature as injecting pure butanol and pure gasoline at n = 200 rpm, Tk = 315K -184.2.1.1 Effect of intake air temperature The effect of the intake air temperature on the evaporation of butanol is less than that of pure gasoline At the end of the compression process, butanol does not continue to evaporate, butanol concentration only increases by about 2.5-11% when the intake air temperature increases from 300K to 345K The density of butanol and the concentration of butanol vapor are slightly increased when increasing the intake air temperature from 300 to 315K 4.2.1.2 Effect of engine speed The spraying time is long, so the time for evaporation decreases when the engine speed increases However, when increasing the speed of the turbulence of air in the combustion chamber, it increases the convection heat transfer between the air and fuel droplets; therefore, resulting in an increase in the evaporation rate For a separated butanol spray (Bu100), the effect of increasing the engine speed on the evaporation of butanol droplets is weaker than that in the case of pure gasoline In addition, the evaporation rate of butanol spraying takes place later and ends earlier, mainly taking place at the end of the charging process and early of compression process In general, increasing the engine speed will reduce the ability of butanol to evaporate completely because butanol does not evaporate at the end of the compression process due to low saturation pressure The equivalent ratio in the case of using gasolinebutanol blends is lower than that in the case of using pure gasoline as increasing the engine speed In the case of Bu50 mixed injection, the evaporation rate in the compression process is significantly improved compared to the separate butanol spray case, especially at high engine speed of 4000-4500 rpm Mixing of butanol and gasoline with a good solubility of butanol will increase -19saturated vapor pressure and evaporation of fuel droplets at the end of the compression process 4.2.2 Evaluate the effect of spray configuration on the process of evaporation and mixture formation 4.2.2.1 Compare blended injection with dual injection The advantage of injecting blends improves evaporation efficiency of butanol and increases butanol concentration in blends The advantage of dual injection is to allow the fuel to evaporate completely at the end of the compression process 4.2.2.2 Compare spray on the 1-side and 2-side intake ports When spraying on one side, heat transfer from air to particles occurs only on one side of the cylinder, reduces the local temperature, slows the evaporation rate In the case of two-side injection, the fuel is sprayed separately through two nozzles located in two symmetrical intake ports Fuel particles diffused in a wider space improve the heat transfer between air and fuel particles At the end of the compression process, the fuel vapor concentration reaches the same value when injected blends from one side and injected blends from both sides Injected blends in one side using two symmetric intake ports creates a high vapor concentration and equivalent ratio in the horizontal direction with a high value at the center of the combustion chamber and the area far from the exhaust This is the basis to select the appropriate spark plug position to reduce the delay time and knock combustion for the engine -20- Figure 4.22: Effects of engine speed on evaporation rate when gasoline injected 4.2.2.3 The influence of injection timing The results show that when injection at 10 oCA, the evaporation process takes place when the piston speed is not high, the low turbulent kinetic energy of the air flow leads to lower final vapor concentration at 30 oCA When injecting at later than 30oCA, the evaporation process is not completed at the end of the compression process, especially in the case of injecting blends The vapor concentration of the fuel at the end of the compression process corresponds to the timing at 60oCA injection about 10% lower than the timing at 30oCA injection, nearly equal to the timing at 10oCA injection At the time of injecting at 10oCA and 30oCA, there is no significant difference in the distribution of fuel vapor on the cross-section of the combustion chamber However, at the time of injecting at 60oCA, the difference in fuel distribution becomes remarkable -214.2.3 Evaluate the effect of direct injection (DI) in the combustion chamber and port injection (PI) Direct injection (DI) is located in the middle of the cylinder head, while the port injection (PI) is placed in front of the port intake The results showed that during the injection process, the evaporation rate of BuDI-GPI was the highest, followed by GDI-BuPI and the lowest was the blended DI Specifically, at the end of the compression process, the fuel vapor concentration using DI case is 10% smaller than that of GDI-BuPI and BuDIGPI cases However, the mixture of DI case is more homogeneous than BuDIGPI case, and areas with a high concentration of fuel vapor are found closed to the wall of cylinder Figure 4.29: Evaporation rate (Er) and fuel density (Fv) using DI blends and DI dual injection at Xj = mm Chapter 5: CONCLUSIONS AND DISCUSSION The thesis has performed experimentally on a Daewoo A16DMS engine within the load ranged from 10-70% of the throttle opening and at a speed of about 1250-4250 rpm The results show that when using a gasolinebutanol pre-blended with a butanol ratio of 10% to 50%, the engine presents almost identical economic and technical features and improves emissions compared to that of using pure gasoline -22- Brake torque and power output of the engine tend to decrease when increasing the ratio of butanol in the blends with reduction of torque and power are not exceeding 21% When Bu10-Bu30 are used, at a load of 3070% throttle opening level, the torque and power of the engine are almost equal to those of Bu0, with a reduction of less than 5% When Bu40-Bu50 are used, many disadvantages in technical feature are found This is even more evident at high load (70 % throttle opening level) and low load (10 % throttle opening level), e.g., with break torque decreases on an average value over 15% - Specific fuel consumption rate tends to increase, and specific energy consumption tends to decrease when increasing the ratio of butanol in gasoline-butanol pre-blended, e.g., an increase in fuel consumption below 22% At the load level corresponding to 30-70% throttle opening level, Bu10Bu30 are used, the pre-blended does not increase the specific fuel consumption to be more than 5% Even the specific fuel consumption as using Bu10 and Bu20 reduces slightly compared to that of Bu0 At the load level of 10% throttle opening level, only Bu10 presents a better specific fuel consumption, while Bu20-Bu50 increase the engine's specific fuel consumption by more than 7% compared to that of Bu0 - Increasing the proportion of butanol in gasoline-butanol fuel reduces CO, HC emissions, but increases NOx emissions The reduction in CO emissions is up to 15% and HC up to 30% as using Bu10, but NOx emissions increase significantly by 42% for the same blend However, at a high ratio of butanol in gasoline (Bu40-Bu50), HC emissions tend to increase, and NOx emissions tend to decrease again - When the engine works at a low or too high load or in combination, it reduces the economic, technical and pollution features of the engine The -23significant impact occurred when the engine uses gasoline-butanol blended with a butanol ratio of over 30% Based on gasoline / butanol blended model of the one-side intake ports on the Daewoo A16DMS engine, this thesis develops the engine structure into a spray configuration from two separated sides (gasoline/butanol) and a combination of port injection with direct injection - Under the same operating conditions, butanol has a lower evaporation rate than pure gasoline Gasoline almost evaporates during the spraying process, but butanol evaporates primarily from the middle of the loading process and in the middle of the compression process The temperature of the fuel during charging and compression when spraying butanol is only slightly lower than that when injecting fuel - Air mixing at the end of the compression process have a higher equivalent ratio when increasing the intake air temperature or increasing the engine speed The effect of increasing the intake temperature and increasing the engine speed to the evaporation of butanol is weaker than gasoline When the intake air temperature increased from 300K to 315-345K, the fuel vapor concentration increased by 2.5-11%, 6-16%, respectively, with separate butanol spray and gasoline injection When increasing the engine speed from 2000 rpm to about 3000-4500 rpm, the equivalent ratio of butanol-air mixture increased from 0.94 to 1.01-1.37, while the equivalent coefficient of gasolineair mixers increased from 1.25 to 1.37-1.95, respectively - Injecting the gasoline-butanol blended improves the evaporation of butanol compared to gasoline/butanol dual injecting However, injecting the blend can make the evaporation of the gasoline not completed Dual injection of gasoline/butanol increases the evaporation of gasoline completely However, it is difficult for butanol to completely evaporate, in this case, butanol should be sprayed early compared to gasoline -24- Two-sided injection increases homogeneity for the mixture, dual injecting two sides of gasoline/butanol will stratify the butanol in the combustion chamber, the half of the cylinder has a higher Bu ratio than the right half of the cylinder - Injection blends on a two-way intake port leads the mixture with a high concentration of fuel vapor and a high equivalent ratio; therefore, the fuel is concentrated in the center of the combustion chamber and away from the outlet This results in the reduction of delay time and reduces the knock combustion in the engine - The evaporation rate of fuel using PI is faster than that of DI The evaporation rate of BuDI-GPI is highest, GDI-BuPI is medium, then DI is lowest at the same working condition of engine DI provides a better homogeneous mixture compared to that of BuDI-GPI and GDI-BuPI RECOMMENDATIONS AND DIRECTION This study provides important insights into the combustion and emissions of gasoline-butanol mixtures in ignition engines Adding butanol to gasoline does not significantly alter the engine's technical performance, but at the same time significantly reduces pollution emissions Due to the difficult ability of butanol to evaporate under low temperature and large throttle opening, technical measures are needed to spray butanol separately into the combustion chamber at the beginning of the charging process Studying the gasoline-butanol mixture on different types of engines as well as real-world testing during the operation of the car for more accurate conclusions Researching technical and economic indicators, pollutant emissions with gasoline-butanol blended fuels with a higher percentage of butanol volume proceeds to a practical test with this fuel -25LIST OF ARTICLES PUBLISHED Huynh Tan Tien, Tran Van Nam, Nguyen Dinh Lam, “Advances in Butanol production and use as a renewable fuel” Journal of Science and Technology-The University of Danang, ISSN 1859-1531, Vol 3(76), Tr 57-60, 2014 Huynh Tan Tien, Phan Minh Duc, Tran Van Nam, Dang The Anh, “Experimental study of the effect of spark timing on the performance of spark ignition engine when using 30% Butanol blended gasoline fuel” National Conference of Mechanics 2015, ISBN: 978 – 604 – 73 – 3690 – 6, Tr 443-453, 2015 Huynh Tan Tien, Nguyen Quang Trung, “The thermodynamic model calculates gas temperature of spark ignition engine by data of combustion chamber pressure” Journal of Science and Technology-The University of Danang (ISSN 1859-1531), Vol 5[90], p 93-97, 2015 Huynh Tan Tien, Phan Minh Duc, Tran Van Nam, “Experimental study assessing the effect of Butanol blending ratio on gasoline on the performance of spark ignition engine” Proceedings of the National Scientific Conference of 2015 on fluid mechanics, ISSN1859-4182, pp 715-723, 2016 Huynh Tan Tien, Nguyen Quoc Huy, Phan Minh Duc, Tran Van Nam, Nguyen Quang Trung, Duong Viet Dung, “Assessment the Effects of Butanol-Gasoline Blends on Spark-Ignition Engine’s Emission” ICT-Bio 2016, ISBN 978-1-53863421-9, 2016 Nguyen Quang Trung, Huynh Tan Tien, Phan Minh Duc, “The effect of ethanol, butanol addition on the equivalence air-fuel ratio, engine performance and pollutant emission of an SI engine using gasohol fuels” In 2017 International Conference on System Science and Engineering (ISSN 2325-0925), p 579-583, 2017 Bui Van Ga, Tran Van Nam, Nguyen Van Dong, Nguyen Quang Trung, Huynh Tan Tien, “Octane number stratified mixture preparation by gasoline–ethanol dual injection in SI engines” International Journal of Environmental Science and Technology (ISSN 1735-1472), p.1-14, 2018 Huynh Tan Tien, Tran Van Nam, Phan Minh Duc, Nguyen Quang Trung, Duong Viet Dung, “Evaluation of affected butanol ratio in gasoline-butanol blended fuel to ignition delay time of Daewoo A16DMS engine” Proceedings of the National Scientific Conference of 2017 on fluid mechanics (ISSN 1859-4182), p 824-831, 2018 Bui Van Ga, Tran Van Nam, Nguyen Quang Trung, Huynh Tan Tien, "Evaporation and mixture formation of gasoline–ethanol sprays in spark ignition engines with pre-blended injection and dual injection: a comparative study" IET Renewable Power Generation (ISSN 1752-1416), Volume 13, Issue 4, p 539 – 548, 2019 ... gasoline -butanol blends The gasoline -butanol blends were Bu0, Bu10, Bu15, Bu20, Bu25, Bu30, Bu40, and Bu50, indicating the content of butanol in different volume ratios (e.g., Bu10 contains 10% butanol. .. when using gasoline -butanol blends with the butanol concentration is up to 50% New finding of the thesis - Experimental results confirm that it is possible to use gasolinebutanol with the ratio... the gasoline -butanol mixture using on spark-ignition engine and the simulation results of the spraying of gasoline -butanol mixtures on the 1-side port intake It is confirmed that butanol mixed