Fuel Viscosity Research Articles

Influence of Adding High Flash Point, Special Jet Fuel for Brazilian Navy (QAV-5), in Brazilian Marine Gasoil (ODM), on Fuel Viscosity, Specific Gravity, Cetane Index and Lubricity

The degradation of Type 5 aviation kerosene, used in navy aircraft, (QAV-5) during the storage period was evaluated by thermal oxidation test (JFTOT) and current gum test. QAV-5 failed to meet jet fuel specifications after 16 weeks of accelerated aging, due to compromised thermal stability and substantial gum generation. Pure blends of QAV-5 and aviation kerosene and marine diesel oil (QAV-5/ODM) in proportions of 25, 50 and 75% (v/v) were analyzed according to the marine diesel oil (ODM) specification, in week zero and at intervals of four weeks throughout the aging process. Fuel viscosity, specific gravity, cetane number and lubricity decreased as the QAV-5 content in the mixture increased. The viscosity of QAV-5, however, increased with storage time. The employment of pure QAV-5 diesel engines is not advisable unless the use of aviation fuel is expressly permitted. By the fuel haze lubricity test (FLHT), QAV-5/ODM blends with up to 88% (v/v) QAV-5 content can be used in diesel engines without damaging the fuel system. However, confirmation by standard high frequency reciprocating rig (HFRR) testing would be advisable for QAV-5/ODM mixtures with QAV-5 volumetric content above 75%.

Clove oil additives in vegetable oil: an assessment of fuel properties

Vegetable oil, obtained from plants such as coconut or Jatropha curcas, serves as a valuable renewable energy source. Nonetheless, it presents certain limitations in comparison to diesel fuels, namely, low volatility and high viscosity. One straightforward approach to overcome these limitations is the addition of high-volatility oil and low-viscosity oil. In this study, we incorporated 10% clove oil into coconut oil and Jatropha curcas oil. Fuel properties, including density, viscosity, flash point, and heating value, were measured in accordance with international standards. Additionally, Thermogravimetric Analysis (TGA) testing was performed to detect decomposition during the heating process. The findings indicated that the addition of clove oil increases density (from 0.922 g/ml to 0.934 g/ml), while other properties decrease, such as viscosity (from 30.12 cst to 27.7 cst), flash point (from 286°C to 182°C), and heating value (from 37.1 MJ/kg to 35.8 MJ/kg). TGA demonstrated that the inclusion of clove oil resulted in increased decomposition within the temperature range of 200°C–400°C, suggesting that clove oil falls into the category of medium-volatile oils. Although the addition of clove oil were able to modify the fuel properties of vegetable oil, it did not align with the characteristics of conventional diesel fuel and necessitates further modification for practical implementation

Kinematic viscosity prediction of jet fuels and alternative blending components via comprehensive two-dimensional gas chromatography, partial least squares, and Yeo-Johnson transformation.

This work presents an accurate yet simplified partial least squares model to predict the kinematic viscosity of conventional and alternative jet fuels at -20°C using comprehensive two-dimensional gas chromatography coupled to a flame ionization detector (GC×GC/FID). Three different normalization methods (mean-centering, logarithmic, and Yeo-Johnson) were evaluated to identify their impact in the prediction of middle distillates' physical properties. Results using Yeo-Johnson transformation exhibited improved viscosity prediction capabilities over the validation set with a mean absolute percentage error of 5.3%, a root-mean-squared error of 0.23, and a coefficient of determination (R2 ) of 0.9404 using only 10 latent variables. Unlike previously reported correlations, this model allowed the identification of specific hydrocarbon groups and carbon numbers that drive jet fuel viscosity at low temperatures. The presence of even small amounts of large branched-alkanes (C15 -C17 ), dicyclic-alkanes (C10 ), and cycloaromatics (C11 ) have the potential to strongly increase the kinematic viscosity of jet fuels. Contrastingly, light monocycloalkanes and branched-alkanes (≤ C10 ) were associated with lower viscosity values. Novelly, this model suggests the implementation of Yeo-Johnson transformations to predict the physical properties of middle distillates to further improve the performance metrics of partial least squares models based on GC data.

Development of empirical correlations for density and viscosity estimation of ternary biodiesel blends

This study aims to investigate the density and viscosity of ternary biodiesel blends. Fuel density and viscosity play an important role in the fuel injection system, flame propagation, and combustion process in compression ignition engine. The density and viscosity of biodiesel are higher than high-speed diesel which is an implication in the commercialization of biodiesel. In the present study, palm oil has been used for the production of biodiesel through the ultrasound-assisted transesterification process. Three different types of fuel additives including butanol, dimethyl carbonate, and plastic oil have been used for the preparation of nine ternary biodiesel blends. The density and viscosity of individual fuels and ternary biodiesel were measured experimentally in a temperature range of 281.51 K–348.15 K. For the prediction of density and viscosity of ternary biodiesel blends, four density and viscosity models were developed. The prediction accuracy of these developed models was assessed by a statistical tool absolute percentage error (APE). Newly proposed exponential regression models predicted well compared to experimental data for density and viscosity values with high regression coefficient 0.9995 and 0.9841 and lower mean absolute percentage of error 0.012 % and – 0.516 % at (348.15 K) temperature respectively. These correlations are significant for the automobile industry in developing fuel pipeline and transport equipment where additives would be present in diesel-biodiesel fuel blends.

Влияние жидких горючих компонент на вязкость водоугольного топлива

The paper presents the experimental studies of coal-water fuel viscosity and suspensions with addition of small amount of various liquid combustible components (isopropyl alcohol, liquid wastes of rubber products processing, and used engine oil) performed. The results show that a liquid combustible component introduced into the suspension causes an increase in the viscosity of the fuel, since the viscosity of the considered liquid combustible components is higher than the viscosity of water. It has been established that the viscosity of slurry fuels based on 3B, D, and T grade coals increases with the increase in the combustible components concentration in the liquid, as less viscous water is replaced by a more viscous substance. Slurry fuel based on 3B grade coal has been determined to have the highest viscosity among the three studied grades, while the slurry fuel based on T grade coal has the smallest viscosity. It has been established that coal-water fuels with addition of a small amount of various liquid combustible components can be used for combustion in boiler units furnaces, since their viscosity and fluidity remain within acceptable limits.

Influence of Diesel Fuel Viscosity on Cavitating Throttle Flow Simulations under Erosive Operation Conditions.

This work investigates the effect of liquid fuel viscosity, as specific by the European Committee for Standardization 2009 (European Norm) for all automotive fuels, on the predicted cavitating flow in micro-orifice flows. The wide range of viscosities allowed leads to a significant variation in orifice nominal Reynolds numbers for the same pressure drop across the orifice. This in turn, is found to affect flow detachment and the formation of large-scale vortices and microscale turbulence. A pressure-based compressible solver is used on the filtered Navier–Stokes equations using the multifluid approach; separate velocity fields are solved for each phase, which share a common pressure. The rates of evaporation and condensation are evaluated with a simplified model based on the Rayleigh–Plesset equation; the coherent structure model is adopted for the subgrid scale modeling in the momentum conservation equation. The test case simulated is a well-reported benchmark throttled flow channel geometry, referred to as “I-channel”; this has allowed for easy optical access for which flow visualization and laser-induced fluorescence measurements allowed for validation of the developed methodology. Despite its simplicity, the I-channel geometry is found to reproduce the most characteristic flow features prevailing in high-speed flows realized in cavitating fuel injectors. Subsequently, the effect of liquid viscosity on integral mass flow, velocity profiles, vapor cavity distribution, and pressure peaks indicating locations prone to cavitation erosion is reported.

The effect of water phase content in coal-water fuel on regularities of the fuel ignition and combustion

Despite all efforts, alternative energy sources cannot meet the growing energy demand of humanity at the moment; and coal keeps its position as an energy source. One the main problem of the coal-water fuel utilizing is to find the balance between its rheological properties, mainly its viscosity, which defines the efficient feeding and atomization of fuel, and combustion efficiency. Fuel viscosity is determined by the fraction of the water phase in fuel. On the other hand, water can influence negatively the combustion process. This paper describes the results of the experimental investigations on the influence of the water phase contents in the coal-water fuel on its combustion efficiency. It was found, that there is an optimal value of the water phase in the coal-water fuel. This optimal value is independent on general combustion parameters like the temperature of the oven medium and source coal metamorphic stage. It characterizes the rational combination of chemical and thermal processes involved in the fuel combustion. The results obtained are new and made a significant contribution to knowledge. They allow changing the viewpoint on the development of the methods for improvement of the utilizing of such type of fuel.

Study of physical-chemical properties for 2nd generation ethanol-blended diesel fuel in India

The present study pertains to glorify the significance of physical and chemical properties of blended diesel fuel with 2nd generation ethanol when applied to compression ignition engine. The assessed fuel properties are density, kinematic viscosity, Cetane number, calorific value, sulfur content and flash point for the prepared blends with respect to fuel quality standards. The results are examined based on present stipulations set for fuel quality rendering Bharat Stage VI standard norms in India. Fuel density and viscosity got slightly decreased with the aggregate of 2nd generation ethanol concentration, at the same time sulfur content also witnessed a similar trend. Cetane number also decreased considerably with the inclusion of 2nd generation ethanol content in diesel fuel. Use of 2nd generation ethanol in diesel fuel will expand markets for agricultural commodities and generate extra revenue from 2nd generation ethanol which is produced from waste residuals of the crops. To achieve stringent emissions regulations and government declarations of increasing biofuel usage can be succeeded by adopting 2nd generation ethanol-blended diesel as a commercial fuel in India. Tested 2nd generation ethanol-blended diesel fuel displayed comparable properties values to those of pure diesel fuel. All verified properties were within the standard limits of diesel fuel. It includes an incisive discussion on the feasible effects of fuel property variation with 2nd generation ethanol-blended diesel fuel concentration. The extreme concentration of 2nd generation ethanol in diesel fuel that can meet the essential characteristics within the range for diesel engine application has been being assessed here.

Properties and characteristics of various materials used as biofuels: A review

Exhausting vitality assets at a disturbing rate urges analysts to scan for different materials that can be utilized as biofuels. Sustainable properties and eco-accommodating nature of biodiesel has made it most well-known among different other options to petroleum products. Transesterficiation process is observed to be most reasonable for creation of methyl esters. This procedure basically relies upon temperature, molar ratio, type of catalyst used, speed of stirring the oil and time. Fuel density, viscosity, flash point, cetane number, calorific value, cloud point, pour point and fire point likewise should be considered while producing biodiesel for diesel engines. A review of biodiesel arranged from different materials is displayed in the present study. It was uncovered that for creation of biodiesel with alluring characteristics it should have molar proportion of 1:6 with KOH as catalyst and should be mixed at a speed of 700 rpm for an hour at a temperature of 65°C. Fuel properties like flash point, fire point, calorific value, viscosity, density and cetane number are very much similar to diesel.

Formulation of a fuel spray SMD model at atmospheric pressure using Design of Experiments (DoE)

Abstract Herein we describe the application of historical data design under response surface methodology to formulate the correlation of the fuel spray SMD (Sauter Mean Diameter) with factors (viscosity, fuel injection pressure, air-blast pressure). The Design Expert software was used to analyze the experimental data to obtain the equation between the factors and the response. The range of the values of variables used in this experiment were viscosity of the fuels 9.71 × 10−4 Pa–1.207 × 10−3 Pa, the fuel injection pressure 0.1–1.0 MPa, the air-blast pressure from 0 Pa to 2000 Pa and a total of 120 test points were conducted. The data were converted into logarithmic scale in order to utilize the linear fitting function of the DoE (Design of Experiments). According to the ANOVA (analysis of variance), the most influential factor to the fuel spray SMD is fuel injection pressure, followed by fuel viscosity and air-blast pressure. R2 value of 0.9339 demonstrated that the regression equation obtained by historical data design fits the experimental results consistently.

Rozdíly v reologickém profilu motorové nafty a bionafty B30

Biodiesel represents a promising alternative to regular fossil diesel. Fuel viscosity markedly influences injection, spraying and combustion, viscosity is thus critical factor to be evaluated and monitored. This work is focused on quantifying the differences in temperature dependent kinematic viscosity regular diesel fuel and B30 biodiesel fuel. The samples were assumed to be Newtonian fluids. Vis­co­si­ty was measured on a digital rotary viscometer in a range of 0 to 80 °C. More significant difference between minimum and maximum values was found in case of diesel fuel in comparison with biodiesel fuel. Temperature dependence of both fuels was modeled using several mathematical models – polynomial, power and Gaussian equation. The Gaussian fit offers the best match between experimental and computed data. Description of viscosity behavior of fuels is critically important, e.g. when considering or calculating running efficiency and performance of combustion engines. The models proposed in this work may be used as a tool for precise prediction of rheological behavior of diesel-type fuels.

Energy Loss in Pulse Detonation Engine due to Fuel Viscosity

Fluid viscosity is a significant factor resulting in the energy loss in most fluid dynamical systems. To analyze the energy loss in the pulse detonation engine (PDE) due to the viscosity of the fuel, the energy loss in the Burgers model excited by periodic impulses is investigated based on the generalized multisymplectic method in this paper. Firstly, the single detonation energy is simplified as an impulse; thus the complex detonation process is simplified. And then, the symmetry of the Burgers model excited by periodic impulses is studied in the generalized multisymplectic framework and the energy loss expression is obtained. Finally, the energy loss in the Burgers model is investigated numerically. The results in this paper can be used to explain the difference between the theoretical performance and the experimental performance of the PDE partly. In addition, the analytical approach of this paper can be extended to the analysis of the energy loss in other fluid dynamic systems due to the fluid viscosity.

Application Analysis of the Fuel Viscosity and Temperature Control System Based on the Sliding Mode Theory

With the shortage of the petroleum resources day by day, the fuel oil price is becoming higher and higher. The ship companies want to use the heavy diesel oil and inferior fuel with lower price for the marine diesel. Temperature is a variable with great inertia. Using the PID control algorithm, which will lead to the consequence of over correction in the controlling process, the advantage of sliding mode variable structure control is the small over correction. In this paper, based on thermodynamics and heat transfer theory, the mathematical model of temperature control system is built, the sliding mode movement equation and the sliding mode variable structure controller is obtained. This makes the application of temperature control take the advantage of sliding mode variable structure control.

Measurement of Bunker Oil / DME Blended Fuel Viscosity for Diesel Engine Application

Currently, around 80% of large ships use Bunker oil (JIS C heavy oil) as the base fuel in marine diesel engines. With its very high kinematic viscosity, this oil is considered the lowest grade of fossil fuel. Thus, it needs to be heated to reduce its viscosity. The authors have reported that the blending of liquefied DME improved the combustion performance of Marine Diesel Oil (JIS A heavy oil). This study aims to clarify the effectiveness of DME – Bunker oil blends. The kinematic viscosity measurement of DME and Bunker oil blended fuel was performed using a capillary tube type viscometer. A pressure cell which contains the viscometer was developed to measure the fuel viscosity while keeping DME in a liquid state. From experiments, it was shown that the cell pressurization resulted in smaller values of kinematic viscosity, and modification was needed to obtain true viscosity values. It was shown that at 323K, the kinematic viscosity of Bunker oil can be reduced drastically from 54~89% with DME blending.

Influence of physical fuel properties on the injection rate in a Diesel injector

This paper presents an experimental investigation of the influence of fuel density and fuel viscosity on the flow characteristics generated from a high pressure Diesel injector, equipped with conical orifices. For this purpose, mass flow rate measurements were performed with nine different fuels over operating conditions from 30 to 180MPa of injection pressure and from 1 to 9MPa of back pressure. Fuel viscosity was varied from 0.6 to 7mm2/s and fuel density from 683 to 876kg/m3 at the operating temperature. Fuel viscosity induces a decrease of up to 10% in the discharge coefficient at low pressure difference but for higher pressure difference, fuel density remains the only fuel property driving the mass flow rate. The discharge coefficient is also a function of the pressure difference at any given Reynolds number under non-cavitating conditions. A correlation is suggested to estimate the discharge coefficient taking into account the fuel properties and the operating conditions.

Study on the Regression Rate of Paraffin-Based Hybrid Rocket Fuels

The most significant problem of a conventional hybrid rocket is very low fuel regression rate. But paraffin-based fuels are shown to have much higher regression rate property. And it was determined theoretically that this was caused by the low viscosity and the low surface tension of the surface melt layer. If that is the case, we can control the regression rates of paraffin-based fuels by changing melt layer viscosity or surface tension. We succeeded to change melting paraffin-based fuel viscosity by adding Ethylene Vinyl-acetate Copolymer. We investigate the relation between the regression rates and viscosities of some melt fuels experimentally and observe the burning surface of fuels with the visualized chamber to reveal the high regression rate mechanism of paraffin-based fuels .

Physical–chemical properties of waste cooking oil biodiesel and castor oil biodiesel blends

This work presents the physical–chemical properties of fuel blends of waste cooking oil biodiesel or castor oil biodiesel with diesel oil. The properties evaluated were fuel density, kinematic viscosity, cetane index, distillation temperatures, and sulfur content, measured according to standard test methods. The results were analyzed based on present specifications for biodiesel fuel in Brazil, Europe, and USA. Fuel density and viscosity were increased with increasing biodiesel concentration, while fuel sulfur content was reduced. Cetane index is decreased with high biodiesel content in diesel oil. The biodiesel blends distillation temperatures T10 and T50 are higher than those of diesel oil, while the distillation temperature T90 is lower. A brief discussion on the possible effects of fuel property variation with biodiesel concentration on engine performance and exhaust emissions is presented. The maximum biodiesel concentration in diesel oil that meets the required characteristics for internal combustion engine application is evaluated, based on the results obtained.

Estimating the Viscosity of Vegetable Oil and Biodiesel Fuels

Among the various alternative fuels, vegetable-oil-based fuels have been attracting greater attention as a promising alternative to fossil diesel fuel in compression ignition (CI) engines. Fuel viscosity has a definite effect on fuel injection, spray development, and combustion processes of CI engines; hence, the viscosity estimation of new candidate fuels is significant. This paper discusses the methodologies used to estimate the viscosities of vegetable oil and biodiesel fuels, based on their fatty acid composition. While the methyl ester composition of biodiesel is directly related to the fatty acid composition of the oil, a basis for determining the triglyceride composition to estimate the straight vegetable oil viscosity is elucidated in the paper. The proposed methodologies are validated over a wide range of available viscosity data for vegetable oils and biodiesel fuels of varying composition and for varying temperatures. A comparison of the estimated viscosities with the measured values for 13 veg...

Electrorheology improves engine efficiency

Improving engine efficiency and reducing pollutant emissions are extremely important. Here, we present our fuel injection technology based on physics principle that application of electrorheology can reduce the viscosity of petroleum fuels. A small device is introduced just before the fuel injection, producing a strong electric field to reduce the fuel viscosity, resulting in much smaller fuel droplets in atomization. As combustion starts at the droplet surface, smaller fuel droplets lead to cleaner and more efficient combustion. Both lab and road tests confirm that this technology improves fuel mileage significantly.

Electrorheology Leads to Efficient Combustion

Improving engine efficiency and reducing pollutant emissions are extremely important. Here, we report our fuel injection technology based on the new physics principle that proper application of electrorheology can reduce the viscosity of petroleum fuels. A small device is thus introduced just before the fuel injection for the engine, producing a strong electric field to reduce the fuel viscosity, resulting in much smaller fuel droplets in atomization. Because combustion starts at the droplet surface, smaller droplets lead to cleaner and more efficient combustion. Both laboratory tests and road tests confirm our theory and indicate that such a device improves fuel mileage significantly. The technology is expected to have broad applications, applicable to current internal combustion engines and future engines as well.