JP-8 Combustion Characteristics in a Small Diesel Auxiliary Power Unit

2011 ◽  
Author(s):  
Valentin Soloiu ◽  
April Covington ◽  
Jeffery Lewis ◽  
Jonathan Welch
Keyword(s):  
Diesel Engine ◽  
Heat Losses ◽  
Combustion Characteristics ◽  
Aviation Fuel ◽  
Power Stroke ◽  
Maximum Temperature ◽  
Diffusion Combustion ◽  
Gas Combustion ◽  
Auxiliary Power ◽  
Overall Efficiency

The US Army Single Fuel Forward policy mandates that deployed vehicles must be operable with aviation fuel JP-8. Therefore, an investigation into the influence of JP-8 on a diesel engine’s performance is currently in progress. The injection, combustion, and performance of JP-8, 20–50% by weight in diesel no.2 mixtures (J20-J50) produced at room temperature were investigated in a 77mm indirect injection, high compression ratio (23.5) diesel engine, in order to evaluate its effectiveness for application in Auxiliary Power Units (APUs) at 2000rpm continuous operation (100% load/BMEP 4.78 bar). Due to the viscosity requirements for proper injection the new fuel can contain as high as 100% JP-8 (J100). The blends had an ignition delay of 1.03ms regardless of the amount of JP-8 introduced. J50 and diesel no.2 exhibited similar characteristics of heat release, the premixed phase being combined with the diffusion combustion. The maximum combustion pressure remained relatively constant for all blends, 72.7bar for diesel and decreased slightly by 0.40bar for J50, with the peak pressure position being delayed by 0.5CAD for the J50. The instantaneous volume-averaged gas combustion temperature reached 2162K for diesel versus 2173K for J50; displaying a 1.2CAD delay in the position of the maximum temperature and retaining the higher temperature for a longer duration for J50. The heat flux in the engine cylinder exhibited comparable maximum values for all blends (diesel: 2.12MW/m2, J50: 2.14MW/m2). The cylinder heat losses were at a minimum during combustion before TDC with increased convection losses at TDC for all fuels and the beginning of the power stroke. The heat losses associated with the system increased slightly with the addition of JP-8. The BSFC for diesel no.2 was 242(g/kW/hr) and increasing by only 0.7% for J50. The engine’s mechanical efficiency displayed similar values for all blends, 83% and decreasing by only 1% for J50. Taking into account each fuels’ corresponding density, the engine’s overall efficiency remained relatively constant at 29% with the addition of the JP-8. The engine investigation demonstrated that up to 50% JP-8 by weight in diesel can be injected and burnt in a small diesel engine with a combustion duration of approximately 5ms, while maintaining the engine overall efficiency. The study validates JP-8 as an excellent source for power generation in a diesel APU based on its combustion characteristics. The next stage of research shall be the full emissions investigation.

Methyl Oleate Evaluation as a Model Fuel for Peanuts FAME, in an Indirect Injection Diesel Engine

2012 ◽  
Author(s):  
Valentin Soloiu ◽  
Jabeous Weaver ◽  
Marvin Duggan ◽  
Henry Ochieng ◽  
Brian Vlcek ◽  
...  
Keyword(s):  
Diesel Engine ◽  
Methyl Oleate ◽  
Mechanical Efficiency ◽  
Combustion Characteristics ◽  
Heat Fluxes ◽  
Diffusion Combustion ◽  
Combustion Modeling ◽  
Ultra Low Sulfur Diesel ◽  
Auxiliary Power ◽  
Model Fuel

This study investigates the combustion characteristics of methyl oleate (oleic FAME) produced from oleic acid. This compound is the main fatty acid component of peanut FAME, a potential renewable biofuel. Methyl oleate has been suggested in our previous work as a reference fuel or surrogate for biodiesel for advanced research (simulation and experiments), or as an enrichment compound to improve biodiesel’s fuel properties. This investigation compares the combustion and emissions characteristics of methyl oleate to peanut FAME and ultra-low sulfur diesel No. 2 (ULSD), in a single-cylinder indirect injection diesel engine intended for use as an auxiliary power unit. The dynamic viscosity of peanut FAME (P100) and Methyl Oleate (O100) was found to be 5.2 cP and 4.3 cP, respectively, at 40°C. It was determined from the ASTM standards for biodiesel that up to 50% FAME could be run in the engine. The lower heating value of P100 and O100 was 36 MJ/kg and 37 MJ/kg respectively, compared to 42.7MJ/kg for ULSD. With a combustion time of 2ms, P50 and O50 have shown similar combustion characteristics with ignition delays of about 1 ms at 2200rpm, 6.2 imep (100% load). The P50, O50, and ULSD heat release, with premixed phase combining with diffusion combustion, produced maximum values of 20.3 J/CAD, 22.7 J/CAD, and 21.9 J/CAD respectively. The heat fluxes were calculated by the Annand model, and a 2% increase in maximum total heat flux was observed for O50 compared with a maximum value of 1.95 MW/m2 for ULSD and P50. The mechanical efficiency of 77% was similar for all tested FAME blends and ULSD. The NOx increased for P20 by 6% compared with ULSD while for P50 it was similar to the ULSD values. The NOx emissions of methyl oleate showed a similar trend with that of ULSD. The soot values were relatively constant for all of the methyl oleate blends and increased by 14% for P50 when comparing both fuels to ULSD. The findings support the use of methyl oleate as a reference or model fuel for combustion modeling, and as a compound for enriching biodiesel.

Combustion and Emissions Characteristics of a Polypropylene Blended Diesel Fuel in a Direct Injection Compression Engine

2010 ◽  
Author(s):  
Valentin Soloiu ◽  
Yoshinobu Yoshihara ◽  
Kazuie Nishiwaki ◽  
Yasufumi Nakanishi
Keyword(s):  
Diesel Engine ◽  
Heat Release ◽  
Diesel Fuel ◽  
Direct Injection ◽  
Injection Pressure ◽  
Injection System ◽  
Maximum Temperature ◽  
Diffusion Combustion ◽  
Combustion Properties ◽  
Blended Fuel

The authors investigated the formulation, combustion and emissions of polypropylene (PP)–diesel fuel mixtures in a direct injection diesel engine. The fuel has been obtained by an original technology they developed, in which the low or high density polypropylene (LDPP, HDPP), have been mixed in a nitrogen atmosphere at 200 °C, 10–40% by wt. in diesel fuel. The kinematic viscosity of the polypropylene-diesel fuels was investigated between 25–250 °C and the results showed that viscosity of the plastic mixtures is much higher than that of diesel alone, ranging from 10 cSt to 500 cSt, and depending on the plastic structure, content, and temperature. The TGA and DTA analysis has been conducted to investigate the oxidation and combustion properties of pure PP and polymerdiesel fuels. The results showed that at about 125 °C, the LDPP melts, but does not decompose up 240 °C, when the oxidation starts, and has a peak of heat release at 340–350 °C, and the process is completed at 400 °C. The engine’s injection system used, was a piston-barrel type pump, capable of an injection pressure of 200 bars. The injector had 4 × 0.200 mm nozzles with a conical tip needle. The 25% PP-diesel mixture had a successful ignition in a direct injection 110 mm bore, omega combustion chamber engine. The ignition delay for polypropylene-diesel mixtures was longer by about 0.5 ms (at 1200 rpm), compared with diesel. The heat release showed a different development compared with the reference diesel fuel, the premixed phase being inhibited while a slow diffusion combustion phase fully developed. The maximum combustion pressure has been 83 bars for diesel and decreased by 2 bars for the blended fuel, while the bulk gas maximum temperature (calculated) reached about 2500 K for diesel vs 2600 K for polypropylene mixture. The heat flux calculated by the Annand model has shown lower values for diesel fuel with a maximum of about 2.7 MW/m2 compared with 3.0 MW/m2 for PP blended fuel with similar values for convection flux for both fuels at about 1.57 MW/m2 and a higher radiation flux of about 1.44 MW/m2 for PP fuel versus 1.27 MW/m2 for diesel. The heat lost during the cycle shows low values for the premixed combustion stage and increased values for the diffusion stage for both fuels. The exhaust temperatures have been practically identical for both fuels for all loads, with emissions of NOx, and CO reduced by 40% for the alternative fuel, while the CO2 exhibited almost the same values for both fuels. The smoke emissions decreased by 60–90% for the polypropylene blended fuel depending on the load, The engines’ overall efficiency was slightly lower for PP fuel at low loads compared with diesel combustion but at 100% load both reached 36%. The study showed that the new formulation process proposed by the authors is able to produce a new class of fuels from diesel blended with low density polypropylene, and resulted in hybrid fuels with very promising combustion prospects. The engine investigation proved that 25% PP fuels can be injected and burnt in a diesel engine at a residence time of about 5 ms from the start of injection, and the engine’s nominal power could be reached, with lower emissions than reference diesel fuel.

Combustion Characteristics of a Single-Cylinder Open-Chamber Diesel Engine

1987 ◽  
Vol 109 (4) ◽  
pp. 419-425 ◽  
Author(s):  
A. C. Alkidas
Keyword(s):  
Diesel Engine ◽  
Heat Release ◽  
Engine Speed ◽  
Combustion Characteristics ◽  
Diffusion Combustion ◽  
Injection Timing ◽  
Crank Angle ◽  
Release Analysis ◽  
Diffusion Burning ◽  
Unburned Fuel

The combustion characteristics of an open-chamber diesel engine were examined by means of heat-release analysis and flame luminosity measurements. Increasing the load was found to decrease premixed burning and correspondingly to increase diffusion burning. During most of the diffusion combustion the burning rate of the fuel appeared to be directly proportional to the amount of unburned fuel present in the cylinder. The duration of heat release in crank-angle degrees increased linearly with load and, in general, increased with decreasing engine speed and retarded injection timing. The measured duration of flame luminosity was significantly longer than the calculated duration of heat release, which suggested that emission of radiation continued long after the heat-release reactions ceased.

Modeling and Experiment on Combustion Characteristics for Biomass Rotary Burner

2020 ◽  
Vol 04 ◽  
Author(s):  
Guohai Jia ◽  
Lijun Li ◽  
Li Dai ◽  
Zicheng Gao ◽  
Jiping Li
Keyword(s):  
Combustion Chamber ◽  
Combustion Temperature ◽  
Combustion Efficiency ◽  
Middle Part ◽  
Combustion Characteristics ◽  
Maximum Temperature ◽  
Excess Air ◽  
Element Simulation ◽  
Excess Air Coefficient ◽  
Secondary Air

Background: A biomass pellet rotary burner was chosen as the research object in order to study the influence of excess air coefficient on the combustion efficiency. The finite element simulation model of biomass rotary burner was established. Methods: The computational fluid dynamics software was applied to simulate the combustion characteristics of biomass rotary burner in steady condition and the effects of excess air ratio on pressure field, velocity field and temperature field was analyzed. Results: The results show that the flow velocity inside the burner gradually increases with the increase of inlet velocity and the maximum combustion temperature is also appeared in the middle part of the combustion chamber. Conclusion: When the excess air coefficient is 1.0 with the secondary air outlet velocity of 4.16 m/s, the maximum temperature of the rotary combustion chamber is 2730K with the secondary air outlet velocity of 6.66 m/s. When the excess air ratio is 1.6, the maximum temperature of the rotary combustion chamber is 2410K. When the air ratio is 2.4, the maximum temperature of the rotary combustion chamber is 2340K with the secondary air outlet velocity of 9.99 m/s. The best excess air coefficient is 1.0. The experimental value of combustion temperature of biomass rotary burner is in good agreement with the simulation results.

Design of Energy Saving System for Hybrid Power Loader

2013 ◽  
Vol 288 ◽  
pp. 148-155
Author(s):  
Qi Hui Lv ◽  
Xin Yuan Xiao
Keyword(s):  
Diesel Engine ◽  
Power System ◽  
Environmental Benefits ◽  
Gravitational Potential Energy ◽  
Super Capacitor ◽  
Hybrid Power ◽  
Software Model ◽  
Auxiliary Power ◽  
High Efficient ◽  
Save Energy

In order to reduce loader engine installed power and save energy, we designed the driving scheme of power system for parallel hybrid loader by Analysis of different way of connection between diesel engine and electric motor. We chose ISG power electric multifunction and super capacitor as the core component to design the Loader auxiliary power system and movable arm cylinder gravitational potential energy recovery system. We established ADVISOR software model of hybrid power Loader, and the simulation results show that diesel engine installed power of the hybrid power Loader is reduced by 21%; fuel consumption is reduced by 9.2%. Through optimize control strategy, the diesel engine can always working in high efficient area or idle area. Practical application shows that this design scheme has the potential economic and environmental benefits.

Improving combustion characteristics of diesel and biodiesel droplets by graphite oxide addition for diesel engine applications

2017 ◽  
Vol 41 (14) ◽  
pp. 2258-2267 ◽  
Author(s):  
Jong Boon Ooi ◽  
Jeevan Raj Rajanren ◽  
Harun Mohamed Ismail ◽  
Varghese Swamy ◽  
Xin Wang
Keyword(s):  
Diesel Engine ◽  
Graphite Oxide ◽  
Combustion Characteristics ◽  
Oxide Addition

Performance, emission and combustion characteristics of the diesel engine powered by the nano emulsion of the lemon peel oil biodiesel

2020 ◽  
Author(s):  
Kumarasubramanian Ramar ◽  
Yuvaraja Subramani ◽  
Karthikeyan Paramasivam ◽  
Jayaprabakar Jayaraman ◽  
P. Krishnakanth ◽  
...  
Keyword(s):  
Diesel Engine ◽  
Combustion Characteristics ◽  
Lemon Peel ◽  
Nano Emulsion ◽  
Lemon Peel Oil ◽  
Peel Oil
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