Testing was performed on commercially available 1 kW spark ignition generators that were modified to operate on JP-8 and other heavy fuels. This approach is motivated by the US Military mandate that only one fuel, JP-8, be taken to the battlefield, and the increased electrical demands at the squad and platoon level. Small units require a portable power source that can meet their energy demands, particularly battery charging. While diesel engines can operate on JP-8, their weight limits their mobility at the platoon level. Spark ignition engines have better power density at the 1 kW level, but must be modified to burn logistically available fuel. Multiple approaches have been pursued to enable these engines to operate on JP-8. In the present study, the longer term effects of three approaches are examined and compared to an unmodified spark ignition generator operating on gasoline. These approaches include A) chemically altering the fuel as it flows to the engine to create a higher octane mixture, B) modifying the carburetor and using ether starter fluid to preheat the cylinder, and C) electrically heating the cylinder while modifying the fuel system for direct injection. The different generators were characterized by oil sampling at 15 hour intervals. Oil testing included flash point, viscosity, wear elements, and additives. Oil quality and emissions vary with load. Different approaches to conversion perform better at different loads. It was determined that multiple start-stop cycles with no load resulted in fuel dilution of the lubricating oil in several of the modified engines. Response varied with some of the modified engines maintaining low fuel dilution similar to the gasoline fueled engine while others indicated 15–20% fuel in the oil. During operation at full load, the modified JP-8 burning generators showed 3–5% fuel dilution in the oil while the unmodified gasoline generator was less than 1%. These experiments illustrate the challenges in developing portable, reliable JP-8 burning power sources. While further research and development is needed in each approach, it was shown that converted spark ignition engines are a promising path to portable logistic power. Oil analysis was shown to identify future research and development efforts to improve this technology.

The method of specific entropy generation (SEG) is employed to show how the thermal efficiency of a combined cycle power plant can be improved. SEG is defined as the total entropy generation rate associated with the operation of a power plant per unit flowrate of the fuel burnt in the combustor. In a recent article published in Journal of Energy Resources and Technology, it is shown that the thermal efficiency of a gas turbine cycle inversely correlates with SEG. In this work, we extend the analysis to show that the same relation between the thermal efficiency and SEG is also valid for a combined cycle. The topping cycle consists of a compressor, a combustor and a gas turbine, whereas the bottoming cycle includes a heat recovery steam generator, a steam turbine, a condenser, a deaerator, a condensate pump and a feed water pump. It is shown that the minimization of SEG is identical to the maximization of thermal efficiency. An illustrative example is presented using the SEG method to improve the efficiency of the combined cycle. The results reveal that 89% of the inefficiencies takes place in the gas turbine cycle. A modified design is then proposed to reduce the efficiency losses in the topping cycle. In the modified design, the thermal energy of the flue gases is first used in a heat exchanger to preheat the air before the combustor. The flue gases leaving the heat exchanger is then directed to the HRSG for producing steam. With this modification, the thermal efficiency and the power output of the combined cycle increase 2.7 percentage points and 20.9 kW per unit molar flowrate of the fuel. Recovering the thermal energy of the flue gases for both preheating the air and producing the steam appears to be more efficient than just producing the steam. Despite the net power production of the bottoming cycle decreases in the modified design, the overall efficiency of the combined cycle increases due to the improvement in the efficiency of the topping cycle.

Large eddy simulation/Flamelet progress variable approach is employed in current research to investigate how flame behaviour is influenced by bluff-body and coflow composition. We used Sydney bluff-body burner as the target burner. Computation grid in cylinder coordinates is approximately 2.7 million in total number, extended to the downstream location 80 times of jet diameter. Three coflow compositions with different oxygen ratio at the same inlet velocity are considered. Comparing to jet flames with hot and diluted coflow, instantaneous and statistical results showed that an introduction of bluff-body preheats the fuel and shortens the flame length. At lower oxygen ratio condition, a weaker reaction zone emerged, marked by lower temperature and OH concentration; the flame appeared lifted gradually, leading to a potential MILD combustion. Besides, bluff-body effect behaves differently in these flames: at lower oxygen ratio condition, a large-scale distribution of CH2O appeared as a marker of partial premixing and preignition reaction in recirculation area; on the contrary, in higher oxygen ratio case, the recirculation area brings out more reactive fuel at lower speed and higher temperature, hence ignitable in the vicinity of bluff-body.

Development of alternative, clean and renewable energy production from different hydrocarbon materials helps to partially replace the limited resources of fossil fuels and also help reduce carbon emissions from fossil fuels that drives global warming. Biomass and bio-wastes are renewable and sustainable hydrocarbon resources, which can be used for energy and fuels production along with permanent disposal of plastic wastes. Landfills of wastes is unsustainable with additional problems of non-degradability and growing burden to the environment and society. Co-pyrolysis and co-gasification of biomass with different types of plastic wastes has shown to provide enhanced product yields and quality for syngas and liquid fuel production. To date, limited information is available on the understanding of chars produced from co-pyrolysis. The effect of co-pyrolysis on the type, quality and yield of chars produced is essential for efficient utilization of a wide variety of biomass, bio-waste and plastic waste resources. This paper provides information on the effect of plastic addition to the pyrolysis of biomass as well as the quality and quantity of char produced with different amounts of plastic waste added at different pyrolysis temperatures. TGA reactor was used for all these investigations and the quality of char produced was examined from the perspective of char combustion for energy production. Char is commonly produced as a by-product from pyrolysis and gasification reactors. Carbonization temperatures investigated were in the range of 573–773 K for 30 min using pinewood biomass, while recycled polyethylene terephthalate was used as plastic waste. The investigations revealed that chars produced from co-pyrolysis especially for carbonization temperature (T c ) of 673 K and above behaved completely differently than the chars produced from separate pyrolysis of biomass and plastic waste under the same pyrolysis conditions. These chars produced from co-pyrolysis were more uniform in their behavior in oxidation environment, with higher heat flow for almost similar quantities of chars during oxidation. This was conjectured to be from enhanced quality of chars produced having increased C content (from increased heavy aromatics and efficient loss of volatiles) during co-pyrolysis without any loss of char yield. The char yield was found to be equal or higher during co-pyrolysis compared to the weighted aggregate of individual pyrolysis. These investigations provided novel results on the behavior and capabilities of chars produced from co-pyrolysis of biomass and plastic wastes to provide a new avenue for the quality enhancement of bio-chars and efficient utilization of carbonaceous solid waste resources.

Homogeneous charge compression ignition (HCCI) is a combustion technology which has received increased attention of researchers in the combustion field for its potential in achieving low oxides of nitrogen (NO x ) and soot emission in internal combustion (IC) engines. HCCI engines have advantages of higher thermal efficiency and reduced emissions in comparison to conventional internal combustion engines. In HCCI engines, ignition is controlled by the chemical kinetics, which leads to significant variation in ignition time with changes in the operating conditions. This variation limits the practical range of operation of the engine. Additionally, since HCCI engine operation combines the operating principles of both spark ignition (SI) and compression ignition (CI) engines, HCCI engine parameters such as compression ratio and injection timing may vary significantly depending on operating conditions, including the type of fuel used. As such, considerable research efforts have been focused on establishing optimal conditions for HCCI operation with both conventional and alternative fuels. In this study, numerical simulation is used to investigate the effect of compression ratio on combustion and emission characteristics of an HCCI engine fueled by pure biodiesel. Using a zero-dimensional (0-D) reactor model and a detailed reaction mechanism for biodiesel, the influence of compression ratio on the combustion and emission characteristics are studied in Chemkin-Pro. Simulation results are validated with available experimental data in terms of incylinder pressure and heat release rate to demonstrate the accuracy of the simulation model in predicting the performance of the actual engine. Analysis shows that an increase in compression ratio leads to advanced and higher peak incylinder pressure. The results also reveal that an increase in compression ratio produces advanced ignition and increased heat release rates for biodiesel combustion. Emission of NO x is observed to increase with increase in compression ratio while the effect of compression ratio on emissions of CO, CO 2 and unburned hydrocarbon (UHC) is only marginal.

The evaluation of power plant uprates has traditionally been based on the definition of several ‘typical’ operating modes based on historical data and a — more or less detailed — model of the plant that is compared in current configuration against the same base model including the modifications under consideration. For the economic assessment of the uprate, annual operating hours are allocated to the operating points, and fuel savings and/or additional output predicted by the model due to the modifications are evaluated against the expected investment cost. In this study, the authors demonstrate that this classic approach contains risks in several aspects, in particular: • the representativeness of the ‘typical’ operating modes, • the accuracy of the model, and • the correctness of the assumptions in the allocation of operating hours. Utilizing the example of an actual uprate of a heat recovery steam generator (HRSG) in a large utility plant of an Austrian steel company, a new approach for an evaluation based on ‘big data’ is presented that uses a full year of operational data in hourly granularity for both, the verification of the accuracy of the plant model, and the evaluation of the effect of the uprate. The authors also provide details of the underlying technologies that allow for both, excellent match of operational data with a fully-fledged heat balance software and fast evaluation of tens of thousands of calculation cases.

A series of experiments were performed on a vertical EV burner with a constant coflow air of 873 L /min to generate turbulent lean premixed flow in order to study the impact of the addition of Acetylene/Argon mixture to the liquefied petroleum gas (LPG) on the temperature field and flame structure. The fluidics mechanism was inserted at a fixed position inside the entry section of the EV burner assembly. The flow rates of fuel (LPG/C 2 H 2 / Ar) and air were measured using calibrated rotameters. The different volume ratios of the fuel constituents (at a specified fuel flow rate) were admitted via three solenoid valves at the entry section of each stream prior to mixing and monitored using a labview program. The axial temperature profiles at different operating conditions were measured using a bare wire Pt-Pt -10% Rh (type S) thermocouple of wire diameter 250 μm. Flame images were obtained — before and after fluidics insertion — using a high resolution Canon 6D 20MP digital camera. The selection of the different considerated cases was based on flame stability. The experimental program aims at identifying and analyzing the changes in flame characteristics (flame length, axial profiles of mean gas temperature, NOx concentration and overall combustion efficiency) resulting from the insertion of fluidics while considering different proportions of the fuel constituents) (including pure LPG, as a reference case). In all experiments flame stabilization was ensured. The results obtained indicate the following: it was noticed that in most cases of pure LPG only, and other mixtures the images shows increase in both the length and luminosity of the flame as a result of higher degrees of swirl due to the fluidics insertion while the temperature profiles of the different flames were changed. It was indicated that NOx trend was decreased by 52% while the combustion efficiency was improved by 2.5%.

In this work, the combustion characteristics of semi-coke, coal, and their blends under air conditions were studied. The influence of blending ratio on the combustion characteristics of blended fuels were investigated by thermogravimetric analysis. It was found that the co-combustion of semi-coke and bituminous coal was a complicated process rather than a simple linear superposition, with interaction effect occurring in the co-combustion process. The synergy occurred in the whole combustion process and it was analyzed quantitatively by comparing the interaction coefficient f and the relative root mean square error RMS . The combustion of semi-coke and the blends can be divided to three stages, as well as two stages of coal. In addition, the blends show better combustion behavior with enhancing bituminous coal proportion, and bituminous coal can improve the combustion behavior of semi-coke.

The objective of this paper is to elucidate the recently observed strong correlation between derived cetane number (DCN) and lean blow out (LBO) characteristics for both petroleum-derived and alternative jet fuels, as well as their blends. In order to evaluate the variability of fuel physical and chemical properties for petroleum-derived jet fuels, the fuel property database appearing in the DSIC-PQIS 2013 report are rigorously analyzed and compared against fuel-specific data for 17 petroleum-derived and alternative jet fuels and their blends obtained previously in our works. The global combustion characteristics of each fuel for fuel/air mixture were characterized experimentally by determining their combustion property targets (CPTs) — the hydrogen to carbon molar ratio (H/C ratio), the derived cetane number (DCN), the average molecular weight (MW), and surrogate fuel mixtures and threshold sooting index (TSI). Surrogate mixtures of known hydrocarbon species were blended to match the CPTs of target real fuel. The known chemical functional group distributions of the surrogate mixtures for each fuel or fuel blend were then used to predict well-known fundamental combustion behaviors — reflected shock ignition delay times and laminar flame speeds — through quantitative structure-property relationship (QSPR) regression analyses developed from a validation base of single component, binary and ternary mixture database. The results show that the DCN is capable of representing ignition propensity and flame propagating characteristics for both petroleum-derived and alternative jet fuels as well as their mixtures with high fidelity. Finally, the chemical functional group distributions of the real fuels themselves were directly measured using 1 H nuclear magnetic resonance (NMR) spectra results. QSPR predictions based upon the experimental NMR functional group measurements are shown to provide a rapid, small sample, characterization tool for predicting the above global combustion behaviors of petroleum derived and alternative jet fuel candidates as well as their blends. Through combustor as well as stirred reactor experiments, fuel DCN has been identified as having major influence on LBO in devices that are sensitive to fuel chemical properties.

Combined Cycle Gas Turbine (CCGT) power plant offer operators both environmental and economic benefits. The high efficiency achievable across a wide load range reduces both fuel costs and CO 2 emissions to atmosphere. However, the scale of the power generation plays a major role in determining both cost and efficiency: a modern large centralized CCGT of 600MW output or more will have a full load efficiency in excess of 60% and a very competitive installed cost on a US$/kW basis. The smaller gas turbines required for distributed power applications are not optimized for combined cycle operation, with potential full load efficiencies of a combined cycle scheme ranging from a little over 40% to the high 50s depending on the power output of the gas turbine, the exhaust gas conditions and the plant configuration, while the installed cost is around twice that of a large centralized CCGT on a US$/kW basis. The drawback of a conventional combined cycle plant design is the need for water, which is a scarce commodity in some regions. Air cooling of the CCGT plant can be used to reduce water consumption, but make-up water will still be required for the steam system to compensate for steam losses, blowdown etc. While the lower exhaust gas temperatures of the smaller gas turbines impact the combined cycle efficiencies achievable, they do allow Organic Rankine Cycle (ORC) technology to be considered for an alternative combined cycle configuration. This paper compares both the capital and operating costs and performance of combined cycle power plants for distributed power applications in the 30MW to 250MW power range based on conventional steam and various different ORC configurations.

Semi-coke is a specific solid fuel, which is mainly produced by upgrading low-rank coal. The poor reactivity of semi-coke makes a difficulty to its practical utilization in utility boilers. Previous research was mainly focused on the combustion behavior of semi-coke, while the industrial application has to be understood. In this paper, the effect of co-firing semi-coke and bituminous coal on the operation performance of pulverized boiler was numerically studied. The work was conducted on a 300 MW tangentially fired boiler, and the temperature distribution, the char burnout and NO x production were mainly examined. The results indicate that the incomplete combustion heat loss drops with the increase in semi-coke blending ratio. The NO x concentration increases from 186 mg/Nm 3 for only firing the bituminous coal to 200, 214, and 255 mg/Nm 3 , when the blending ratio was 17%, 33% and 50%, respectively. With enhancing excess air coefficient for the co-firing condition, the combustion efficiency got improved, while NO x production increased very slightly. In general, the boiler is well adapted to co-firing semi-coke, and the semi-coke blending ratio of 1/3 with an excess air coefficient of 1.235 is recommended.

Direct use of propane and butane in Solid Oxide Fuel Cells (SOFCs) is desirable due to the availability of the fuel source, but is challenging due to carbon coking, particularly on the commercially available Ni+YSZ anode. A novel dual chamber Flame-assisted Fuel Cell (FFC) configuration with micro-tubular SOFCs (mT-SOFCs) is proposed for direct use of higher hydrocarbon fuels. Combustion exhaust for propane and butane fuels is analyzed experimentally and compared with chemical equilibrium. mT-SOFC polarization and power density testing in the FFC configuration with propane and butane fuels is discussed. Peak power and electrical efficiency conditions are assessed by varying the fuel-rich combustion equivalence ratio and flow rate. Carbon deposition and soot formation on the Ni+YSZ anode is investigated with a scanning electron microscope. The results indicate that reasonable power density (∼289 mW.cm −2 ) can be achieved while limiting soot formation in the flame and carbon deposition on the anode. Electrical efficiency based on the higher heating value of the fuels is analyzed and future research is recommended. Possible applications of the technology include small scale power generation, cogeneration and combined cycle power plants.

As alternative jet fuels continue to be developed, their impact on combustor performance remains of utmost importance. Alternative jet fuels generally contain few aromatics and differ in alkylated compositions, yielding different chemical and physical properties from those of conventional jet fuels; understanding how these property differences impact combustor performance near limiting conditions is important in certifying their use in blending with petroleum derived fuels or as complete substitutes. Ignition and extinction properties that are associated with Lean Blowout (LBO) are areas of focus for jet fuel certification as they are important safety metrics bounding combustor stability. Previous results for 23 different test fuels in a referee combustor show a strong correlation of Lean Blowout (LBO) with fuel Derived Cetane Number (DCN). This previous study involved fuels with compositions similar to conventional fuels. However, fuels with properties differing significantly from conventional fuels were found to have a weaker correlation with DCN and higher LBO equivalence ratios overall. The surrogate fuels and blends that show the largest discrepancy from the earlier correlation were blends involving highly volatile, low DCN components such as iso -octane prevalent in the early stages of distillation, and less volatile, high DCN normal alkane components such as n -hexadecane, prevalent in the final stages of distillation. Thus, significant differences in fuel reactivity along the distillation curve from those of conventional petroleum derived fuels appeared to exhibit differing LBO character. From these observations, three hypotheses, preferential vaporization, relative droplet lifetimes, and thermal quenching, are proposed and investigated by utilizing the available data. Using normalized power law regressions, distillation simulation methods and Quantitative Structure Property Relation (QSPR) results, the DCN at 34% distillation recovery show a stronger correlation with LBO than the DCN determine for the fuel itself. In this paper, we apply findings to propose fuel compositions to investigate the noted hypotheses by utilizing reactive low molecular weight molecules and a less reactive high molecular weight fuel. The suggested fuel to stress test this hypothesis is a blend of 30 (molar)% n -heptane and 70 (molar)% Gevo Alcohol-to-Jet (ATJ), which is essentially composed of (primarily) 2,2,4,6,6 iso -dodecane and isocetane. If preferential vaporization is significant, then this fuel should be more stable than the “DCN-Law,” i.e. fuels are no more stable than the corresponding DCN allows, would predict.

The Kemper County Project has demonstrated Transport Integrated Gasification (TRIG™) at a 2-on-1 Integrated Gasification Combined-Cycle (IGCC) facility located in Kemper County, Mississippi. Kemper is the largest IGCC project in the world, the first to use lignite as fuel, the first to capture and sell CO 2 , and the first to produce multiple byproducts from initial startup. The facility features two Siemens SGT6-5000F gas turbines, each capable of operating on a high-hydrogen syngas produced in the Transport Gasifiers from locally mined lignite. Using high-hydrogen syngas requires unique modifications to the combustion turbine design. Flame-diffusion combustors, rather than dry low-NO X designs, prevent flashback caused by the high hydrogen content of the syngas. Also, ports added to the turbine compressor casing allow air to be extracted from the compressor and used elsewhere in the plant, supplying up to one half of the air required by the gasifier. The Kemper facility has achieved the integrated operation of both gasifiers, including the production of electricity from syngas by both combustion turbines. Turbine operation on the high hydrogen syngas was smooth both during normal operations and during transitions, with efficiencies meeting or exceeding expectations. This paper describes the Kemper plant design, focusing on the combustion turbine design unique to Kemper. The paper also discusses turbine design challenges specific to Kemper, provides an overview of the robust control scheme used on both syngas and natural gas co-firing operations, and provides preliminary operational and performance results, including inspection findings.

Military systems greatly depend on the availability of energy. This energy comes mostly in the form of burning fuel in order to produce mechanical work or producing electricity. The ability to extract the most out of these systems aligns with the current focus of energy efficiency, not only in the military, but in society at large. In this research, an infrared camera was used to create an infrared map to infer temperature differences on a gasoline-powered generator at steady state operations. These temperature differences were inputted into an experimental phase during which a digitally-controlled hot plate, water block, variable resistor, and digital acquisitions system were used to measure current output from a single TEG for loads of 1, 10, and 100 Ω, respectively. Data were analyzed and the correlation coefficients determined. These coefficients were modeled a single module and then various array configurations for TEGs in COMSOL. Using the findings, a single commercial 56 mm by 56 mm Be 2 Te 3 TEG can yield 0.72 W of power. Simple calculations yield 72 W of power when 100 modules are joined in 10 sets coupled in parallel with each set containing 10 modules in coupled in series. This would require 560 mm by 560 mm or approximately 2 ft. by 2 ft. of system space to be covered.

In order to reduce CO 2 emission from thermal power stations with keeping high thermal efficiency, a new concept of IGCC system, namely oxy-fuel IGCC, has been recently proposed. Hence CO 2 is recycled in the system, the effect of CO 2 recycle on each equipments should be clarified. In this study, the effect of recycled CO 2 injection on coal gasifier performance was investigated by means of three-dimensional RANS-based numerical simulation. For estimating of coal gasifier performance, coal gasification and water-gas shift reaction are key phenomena. Therefore, the partially active site sharing coal gasification model and detailed chemistry of water-gas shift reaction model were implemented. Calculated gasifier was a commercial scale entrained flow coal gasifier whose coal feeding rate is 70 tons per hour. The gasifier consists of a lower combustor part and an upper reductor part. The effect of coal feeding rate into the reductor, R/T, was investigated. The results show that temperature in the combustor decreases with decreasing R/T. In the lower R/T condition, hence air ratio in the combustor decreases, the reducing atmosphere becomes stronger. As a result, coal gasification which is endothermic reaction in the combustor is promoted. Although coal gasification is occurred in the reductor in higher R/T condition, total coal gasification rate is not so promoted compared with lower R/T condition. Due to the above mechanism, the gasification performance becomes higher with decreasing R/T. The results obtained in this study indicate that it is important that how much the higher gasification reactivity in a gasifier is exploited by optimizing local heat balance.

In recent years, global warming and climate change caused by the greenhouse gas emissions has given rise to widespread concerns. CO 2 has been considered as the principal greenhouse gas of interest, and fossil-fuel-fired power plants have been deemed as the largest stationary sources of CO 2 emission. It is imperative to capture CO 2 from these sources to reduce the global CO 2 emissions. Lately, capturing CO 2 from flue gas using solid absorbents shows promising for CO 2 abatement. For the cost-effective CO 2 capture process and the recycling of environmental pollutants, deprecated resources have been utilized for CO 2 capture from flue gas. In this work, fly ashes derived from different raw materials were tried as solid CO 2 sorbents for flue gas treatment. To improve their CO 2 capture capacities, the ashes were modified by different polyamines. An experimental demonstration on CO 2 capture behaviors of fresh ashes and modified sorbents in simulated flue gas atmosphere of 40°C, 15% CO 2 + 15% H 2 O and balanced N 2 was presented in detail with a fixed-bed reactor system. CO 2 capture capacities of fresh ashes were calculated as 0.56 mmolCO 2 /g, 0.32 mmolCO 2 /g, 0.44 mmolCO 2 /g and 0.83 mmolCO 2 /g, respectively. By contrast, CO 2 capture capacities of amine-modified samples had been enhanced as 0.38 mmolCO 2 /g, 0.65 mmolCO 2 /g, 1.07 mmolCO 2 /g, 0.85 mmolCO 2 /g and 1.17 mmolCO 2 /g. The optimal sample of TEPA-modified biomass ash (TEPA-BA) with CO 2 capture capacity of 1.17mmolCO 2 /g was screened. The optimal candidate was then selected for further investigation of the effects of temperature, CO 2 concentration and H 2 O concentration on its CO 2 capture behaviors. The results indicated that CO 2 capture capacity would increase with the increase of temperature in the range of 30 to 40 °C and decrease with the increase of temperature in the range of 40 to 60°C, increase with the increase of CO 2 concentration in the range of 5% to 20%, increase with the increase of H 2 O concentration in the range of 0% to 15% and decrease with the increase of H 2 O concentration in the range of 15% to 20%. The results in this work could provide basic data as a guidance for further applying the sorbents in practical operations.

Coal is regarded as important fuel because of its stable supply and low price, but coal is blamed for its CO 2 emission. Japanese utilities are making efforts to improve thermal efficiency and to expand biomass co-firing. On the other hand, CCS technologies are under development as a countermeasure for global warming and demonstration projects planned in several power stations are announced in world wide. As CO 2 capture from power station requires huge in-house power, thermal efficiency is deteriorated. To make a breakthrough, NEDO started a project to develop the high-efficiency oxy-fuel IGCC system. This system recirculates gas turbine exhaust gas to both gasifier and gas turbine combustor. Recirculated exhaust gas is used both to feed pulverized coal to gasifier and to dilute syngas in gas turbine combustor. The target efficiency is 42% at HHV basis, equivalent to state of the art coal-fired power station. Various studies were done to confirm the concept of this system and to develop fundamental technologies necessary for the system since 2008 to 2014 as NEDO project. Based on the achievements, the project made another step since 2015 as a five-year joint NEDO project with MHI and MHPS. This paper introduces the latest status of this project executed by CRIEPI by referring several related papers.

The depletion of conventional fuel source at a fast rate and increasing environmental pollution have motivated extensive research in combustion modeling and energy efficient engine design. In the present work, a computer simulation incorporating progressive combustion model using thermodynamic equations has been carried out using MATLAB to evaluate the performance of a diesel engine. Simulations at constant speed and variable load have been carried out for the experimental engine available in the laboratory. For simulation, speed and Air/Fuel ratios, which are measured during the experiment, have been used as input apart from other geometrical details. A state-of-the-art experimental facility has been developed in-house. The facility comprises of a hundred horsepower water cooled eddy current dynamometer with appropriate electronic controllers. A normal load test has been carried out and the required parameters were measured. A six gas analyzer was used for the measurement of NOx, HC, CO 2 , O 2 , CO and SO x . and a smoke meter was used for smoke opacity. The predicted Pressure-Volume (PV) diagram was compared with measurements and found to match closely. It is concluded that the developed simulation software could be used to get quick results for parametric studies.

This paper aims at developing a mesoscale combustion based thermoelectric power generator as an alternate to the electrochemical batteries. Most of the micro and mesoscale combustors investigated till date are based on external fuel and air supply systems, which may not be beneficial for a practical system. The proposed design is a standalone system which makes use of the heat conducted through the combustor walls, as an energy source to evaporate the liquid fuel stored in a surrounding tank and supply the vaporized fuel to the combustor. The high momentum fuel (vapor) jet is designed to entrain the ambient air in appropriate proportion so as to form a combustible mixture. The partially mixed fuel/air mixture is fed to a mesoscale combustor and the flame is stabilized by facilitating hot gas recirculation regions. The heat conduction through the combustor walls is controlled by providing an air gap between two concentric, low thermal conductivity, ceramic tubes so as to transmit desirable amount of heat to the fuel tank. Note that the heat lost from the combustor, is recovered via increased enthalpy of the supplied fuel. The hot products then flow over the hot side of a thermoelectric module to generate electricity. The cold side of the module is maintained at relatively lower temperature and the rejected heat is used to boil the stored water. The prototype is designed to produce an electrical power output of 15 W with an overall efficiency of about 3% and endurance of 1 hour in a single fuel (and cold side water) refill. The paper presents detailed thermo-fluid and heat transfer analysis of the constituent components and evaluates the performance of the system.