RON Gasoline Research Articles

Comparative analysis of spark ignition engine performance using RON 95 and RON 100 gasoline fuels

Most of the vehicles used by Malaysians have engines that only require petrol RON 95 to power the engine. However, many people claimed that utilising RON 100 instead of RON 95 for their vehicles will improve engine performance. Furthermore, many people speculate that using oil with a low octane level in an engine with low performance will affect the engine's performance. The goal of this research is to analyse and compare the engine performance and emissions on a spark ignition engine using gasoline RON 95 and RON 100. In this study, a single-cylinder four-stroke engine running with RON 95 and RON 100 has been tested on an engine dynamometer to evaluate the brake power, torque, specific fuel consumption, and exhaust emissions. The emissions from the engines have been determined using a gas emissions analyser. The outcomes of the experiment have been analysed based on engine torque, braking power, and exhaust emissions. Based on the analysis, torque, brake power, and emissions data obtained from the dynamometer engine, RON 100 has a higher and smoother performance than RON 95.

Novel variants conceptional technology to produce eco-friendly sustainable high octane-gasoline biofuel based on renewable gasoline component

The creation of green engine fuels from renewable and sustainable gasoline additives is essential as a consequence of ecological concerns and the energy problem. Bio-alcohols are currently a promising sustainable fuel substitute for gasoline in automotive transportation. In this perspective, the ongoing investigation intends to evaluate the influence of sustainable and renewable petrol additives, like isopropanol, which has outstanding anti-detonation properties and great chemical and physical characteristics on reformable naphtha (HSRN) and light naphtha (LSRN), which possess low chemical and physical characteristics, and low octane rating. Additionally, the second goal is to create biofuel with an eco-octane number of high by blending other gasoline components than those previously indicated. Several gasoline fuels and experimental setups compliant with European standard norms were used to carry out the current work. The results reported that gasoline RON92, RON95, and RON98 were produced based on isopropanol as a renewable and sustainable resource. Moreover, the quantity and quality of light naphtha were maximized. Likewise, the laboratory findings reported that the antiknocking efficiency could be ranked sequentially as isopropanol > reformate > isomerate > fluidized catalytic cracked gasoline (FCC) > PRF-70 > LSRN > HSRN by octane rating. Furthermore, the Reid vapor pressure (RVP) for petrol RON92 was bigger than gasoline RON95 and RON98, unlike the density at 15 °C for gasoline RON 98 was bigger than gasoline RON92 and RON95. Finally, major problems like energy, water scarcity, and the environment affect people all around the world. Two of the earlier environmental and energy-related problems will be resolved by using these sustainable and renewable additions.

EFFECT OF CYLINDER HEAD GASKET ADDITION AND VARYING OCTANE NUMBER GASOLINE TO INTERNAL COMBUSTION ENGINE PERFORMANCE

The aim of this research was to investigate the different impacts of compression pressure on power and torque outputs using gasoline RON 92, RON 95, and RON 100. The study involved experiments using a single-cylinder motorcycle engine with a capacity of 125 cm. The selection of this type of engine is based on the popularity of vehicles in Indonesia that use a single-cylinder engine with a capacity of 125 cm. To modify the compression pressure, variations in the number of gaskets were applied to the cylinder head, with quantities of 1 and 3 gaskets. Dynamometer tests were conducted to measure the engine's performance differences. Throughout the testing, the settings for the main jet, pilot jet, and the number of idle screw rotations on the carburetor remain constant. The findings indicate that the engine with the highest compression pressure of 11.8 Kg/cm, using RON 100 gasoline, produces the highest power output at 7.9 kW, with the highest torque at 10 Nm.

CITRONELLA OIL AS BIOADDITIVES ON SI ENGINE PERFORMANCE CHARACTERISTICS

Current dynamics of world energy supply have driven various innovations by the industry as well as research communities. Fossil fuels, although experiencing a declining interest due to sustainability issues, remain undeniably crucial since they are nearly irreplaceable in some sectors including electricity generation, it is necessary to continuously establish efforts to improve efficiency of those kinds of fuel. In this work, the authors evaluate the potential of locally sourced essential oils, namely citronella, as a fuel additive in a vision of raising the fuel economy of gasoline RON 90. Citronella oil was selected based on a positive hypothesis deduced from its chemical properties, as mentioned in multiple published works. Tests were made on a generator-set powered by gasoline engine using the mixture of RON 90 and citronella oil of various concentrations as the fuels. In addition, a commercial synthetic additive was also tested alongside the essential oil to provide a comparative figure. Meanwhile other investigators suggest a favorable effect of essential oils, our results show that citronella oil additions lead to higher fuel consumption at the same power level. A similar negative effect was also demonstrated by the synthetic additive. The only sector showing positive results is in terms of exhaust temperature where experiments with citronella additives create lower exhaust temperature as compared to pure gasoline and synthetic additives. However, rooms for innovation remain open by exploring other variables such as higher additive concentrations or combining different kinds of essential oils.

Performance of a Single-Cylinder Four-Stroke Engine with High Concentrations of Gasoline-Ethanol-Methanol (GEM)

Several types of alternative fuels have been developed to replace fossil fuels. Alcohols, such as ethanol and methanol, can be blended with gasoline for spark ignition (SI) engines. High octane number and oxygen content in alcohol can increase combustion efficiency. Therefore, our current research investigates the effect of high concentrations of ethanol and methanol mixed in 90 RON gasoline. The mixture was implemented in a 150 cc single-cylinder four-stroke spark ignition (SI) engine without any modifications. Engine testing was carried out with wide-open throttle (WOT) and different engine speeds from 4000 to 10000 rpm. Torque, power, and Air Fuel Ratio (AFR) were measured during experiments on a chassis dynamometer. Our test results found that the higher the methanol fraction in the mixture, the lower the torque generated. To improve engine performance, further research is needed on modified engines so that optimal conditions can be identified.

Application of stable consistency wavelength in optimizing gasoline RON near‐infrared analysis model transfer

AbstractThe purpose of model transfer is to solve the problem that multivariate calibration models cannot be shared among different near‐infrared spectrometers. Taking gasoline as the research object, the transfer analysis of its octane number model was carried out. The gasoline samples collected by two near‐infrared spectrometers of the same type were used as the research object. The screening wavelengths with consistent and stable signals (SWCSS) combined with competitive adaptive reweighted sampling (CARS), uninformative variable elimination (UVE), and successive projections algorithm (SPA) were used to reduce the adverse effects of invalid wavelengths in the SWCSS method; therefore, the analysis ability of the master model to the slave samples was improved. Partial least squares regression (PLSR) models based on SWCSS‐UVE, SWCSS‐CARS, and SWCSS‐SPA algorithms were established, and comparison was made between their analytical capabilities for slave samples and those of SWCSS, direct standardization (DS) algorithm , piecewise direct standardization (PDS) algorithm, and slope/bias (S/B) algorithm. The results shown that the SWCSS‐UVE and SWCSS‐CARS methods can be used to establish models from the 231 and 6 wavelengths selected from the consistent wavelengths, respectively. The root mean square error of prediction (RMSEP) of the gasoline octane number (RON) content of the direct analysis of the spectrum measured by the slave machine was reduced from 5.7490 to 0.3226 and 0.3250, respectively, which was better than the single SWCSS and DS, PDS, and SWCSS‐SPA methods, and was close to the model transfer accuracy of the S/B algorithm. The transfer accuracy of SWCSS‐UVE and SWCSS‐CARS was not much different, but the wavelength variable involved in the model transfer of the latter was much smaller than that of the former, and the AIC value of SWCSS‐CARS was −59.59, which was much smaller than the akaike information criterion (AIC) value of SWCSS‐UVE 398.42.

Low carbon energy technologies envisaged in the context of sustainable energy for producing high-octane gasoline fuel

With increasing issues, concerning the depletion of petroleum fossil fuels and the environment, various researchers have examined an innovative and appropriate surrogated fuel. Various advanced countries maximize alternative fuel to fight against atmospheric alteration. In this perspective, the current research aims to introduce low-carbon energy technologies envisaged in the context of sustainable energy for generating high-octane gasoline fuel. Four gasoline feedstocks were selected for investigation in the present research as materials. Particularly, these components are gasoline additives, such as bioethanol (E), di-isobutylene (DIB), and dimate (D) with baseline motor gasoline stream, like hydrocracked gasoline (HG). To execute the present work, several gasoline fuels and experimental facilities that correspond to European standard regulations were employed. Additionally, the composition of the optimum sample was 50 % of hydrocracked gasoline, 35 % of bioethanol, 10 % of di-isobutylene, as well as 5 % of dimate. Therefore, the optimal gasoline blend provided high-octane gasoline RON 98 with great ecological characteristics. Besides, the experimental results displayed that the antidetonation performance can be varied consecutively as bioethanol > di-isobutylen > dimate > hydrocracked gasoline by octane number. What’s more, the simultaneous incorporation of bioethanol, di-isobutylene, and dimate changed antiknock characteristics, in terms of vapor pressure, the distillation curve, as well as the density in a route that could impact engine operation. Conclusively, the acquired results stated that it might be merits to utilize bioethanol to provide the added value of hydrocracked gasoline, di-isobutylene, and dimate to establish an innovative high gasoline product in RON of 98 considered the restrictions for high olefins content.

Comparative Analysis of Injection of Pyrolysis Oil from Plastics and Gasoline into the Engine Cylinder and Atomization by a Direct High-Pressure Injector

The article discusses the results of experimental studies on the course of pyrolysis oil injection through the high-pressure injector of a direct-injection engine. The pyrolysis oil used for the tests was derived from waste plastics (mainly high-density polyethylene—HDPE). This oil was then distilled. The article also describes the production technology of this pyrolysis oil on a laboratory scale. It presents the results of the chemical composition of the raw pyrolysis oil and the oil after the distillation process using GC-MS analysis. Fuel injection tests were carried out for the distilled pyrolysis oil and a 91 RON gasoline in order to perform a comparative analysis with the tested pyrolysis oil. In this case, the research was focused on the injected spray cloud analysis. The essential tested parameter was the Sauter Mean Diameter (SMD) of fuel droplets measured at the injection pressure of 400 bar. The analysis showed that the oil after distillation contained a significant proportion of light hydrocarbons similar to gasoline, and that the SMDs for distilled pyrolysis oil and gasoline were similar in the 7–9 µm range. In conclusion, it can be considered that distilled pyrolysis oil from HDPE can be used both as an additive for blending with gasoline in a spark-ignition engine or as a single fuel for a gasoline compression-ignition direct injection engine.

Effect of low percentage methanol blends in gasoline RON 90 on fuel volatility characteristics and spark ignition engine performance

Methanol is one of the promising alternative fuel for gasoline that can be made from renewable sources. Methanol has high octane number, which can increase octane number of gasoline. Methanol is also an oxygenate and contain less carbon content than gasoline, so combustion emission can be reduced. Blending methanol with gasoline influences the volatility characteristics of the fuel blend where it could influence engine performance. Fuel used in this study were gasoline RON 90 blended with methanol in percentage of up to 20%. In this study, distillation and Reid vapor pressure were measured, and then engine performance tests were performed using those fuel blends. The obtained result showed that the vapor pressure was increasing with addition of methanol up to 15% with maximum vapor pressure of 74.75 kPa and started to decrease at 20% methanol blends. The distillation curve showed that increasing methanol addition to the fuel blend flattened the distillation curve below the methanol boiling point. Engine performance test results revealed that addition of methanol in fuel blend resulted in decrease of torque, changes in specific fuel consumption, and reduced CO and HC emission.

SMART PRODUCT BLENDING SYSTEM TO MAXIMISE QUALITY

PETRONAS developed a uniquely fast and exact automated fuel blending system that has accelerated the release of quality certification and achieved the perfect gasoline product blend for a Malaysian Refinery. Blending is a critical production process. Up to 13 different hydrocarbon streams from various feedstocks must be precisely blended to produce petroleum products such as Unleaded Gasoline RON 95. The ratio between flow velocities of different blending component streams is of great importance to ultimately achieve the target quality of the product. The ratio is determined based on the individual quality of the blending component. The underlying concept of this innovation is based on the strategy of an online blending with intelligent and fast chemometrics multivariate data analytics to make the necessary adjustment in the ratio of the blending components to meet the product quality. One of the integral parts of chemometrics multivariate data analytics is a spectroscopic analyser equipped with calibration models which enable multivariate prediction. The integration of the spectroscopic analyser and customised blend property control is an authoritarian system whereby it provides real-time data on fuel quality and enables online blending monitoring and control to happen seamlessly. PETRONAS has crafted an automated and integrated online blending system. This innovation has resulted in a more innovative product blending with zero re-blend and minimal quality giveaway in line with Industry 4.0 Best Practice.
 Keywords: Chemometrics multivariate modelling, online blending, spectroscopy

OPTIMASI PARAMETER PROSES PEMBUATAN BIOETANOL SORGUM DAN PENGARUH TERHADAP UNJUK KERJA MOTOR BENSIN

Bioethanol is a renewable fuel that resembles gasoline, bioethanol is produced from fermentation and distillation processes. One of the raw materials that produce bioethanol is Sorghum. Sorghum was chosen because it is superior to other plants. This study aims to analyze fermentation longtime and enzyme composition for the best composition to produce bioethanol from sorghum, and determine the quality of sorghum bioethanol. This research Sorghum bioethanol produced with an alcohol content of 94%. The test and analysis variables used were 31 samples. The results of this study are as follows : The best fermentation time is 4 days, the enzyme and yeast variable for the most volume of alcohol is 7% yeast 5% enzyme, the enzyme and yeast variable for the highest alcohol content is 7% yeast 7% enzyme. Laboratory test results when compared with PERTAMINA's standard regulations, especially Pertalite RON 90, Several parameters have rejected the regulations. Therefore sorghum bioethanol is used as an additive for Gasoline. Sorghum bioethanol is made addictive to gasoline RON 90, namely B10 (bioethanol sorghum 10%) and B20 (bioethanol sorghum 20%). It would cause an increase in the performance of gasoline engines.

Production of high octane gasoline by catalytic cracking of petroleum gasoil with palm’s triglyceride and oleic acid

The use of gasoline with appropriate octane number will affect directly to meet superfine engine performance and avoiding from knocking effect. Improvement of gasoline quality in fluid catalytic cracking process usually is achieved by replacement of new catalyst which needs higher production cost. This research work aimed to describe the alternative method for improving gasoline octane in catalytic cracking by means of feedstock modification using mixture of vacuum gasoil and few of palm’s triglyceride and oleic acid. The experimental work of cracking reaction was performed in a fluid-bed reactor of ACE unit using REY zeolite catalysts at temperature of 530 °C and catalyst-oil ratio of 5.5 g/g. The liquid product was analyzed by a gas chromatograph of simulated distillation to determine yields of gasoline, light cycle oil and bottom product continued by a gas chromatograph of detailed hydrocarbon analysis to obtain hydrocarbon composition and calculated research octane number of gasoline. Analysis of gaseous product was performed using a gas chromatograph of refinery gas analyzer to detect yields of dry gas and LPG, whereas coke deposited on spent catalyst was analyzed using the infra-red method. From the research work, it was found that feedstock prepared from vacuum gasoil added with 5 % refined bleached deodorized palm oil and oleic acid (9:1) had increased gasoline RON from 91.8 to 98.2. The improvement of gasoline octane was contributed by the presence of double-bond fatty acid that triggered promoting effect to aromatisation and hydrogen transfer reactions in the formation of more iso-paraffins, olefins and aromatics in gasoline.

Economic Values and CO2 Simulation on the Application of LPG for Public Fleets in Magelang, Indonesia: Executive Data to Support the Clean City Program

The implementation of the ASEAN Clean Tourist City Standard caused restlessness among public fleet operators and the Department of Transportation of Magelang City. Therefore, this article presents the prediction of economic value and environmental benefits of public fleet in Magelang that will be converted from gasoline to LPG. Investment feasibility parameters, such as Break Event Point (BEP), Net Present Value (NPV), Internal Rate of Return (IRR), and Payback Period (PBP) are presented through three financing scenarios compared with the current gasoline price at the fuel station, RON 88 and RON 90. Simulation results indicate that investment is feasible with the government providing fiscal incentives through the procurement of converter kits. The wages of the public fleet crew under Minimum Wage City will rise by 30 % and 70 % to switch from gasoline RON 88 and gasoline RON 90, respectively. Meanwhile, environmental benefits are also expected to improve, with CO2 emission reduction of 320.46 tons/year or about 11 % of gasoline usage. These two benefits (economics and environmental) are expected to support the clean city program in Magelang City, Indonesia.

Water Injection Benefits in a 3-Cylinder Downsized SI-Engine

<div class="section abstract"><div class="htmlview paragraph">With progressing electrification of automotive powertrains and demands to meet increasingly stringent emission regulations, a combination of an electric motor and downsized turbocharged spark-ignited engine has been recognized as a viable solution. The SI engine must be optimized, and preferentially downsized, to reduce tailpipe CO<sub>2</sub> and other emissions. However, drives to increase BMEP (Brake Mean Effective Pressure) and compression ratio/thermal efficiency increase propensities of knocking (auto-ignition of residual unburnt charge before the propagating flame reaches it) in downsized engines.</div><div class="htmlview paragraph">Currently, knock is mitigated by retarding the ignition timing, but this has several limitations. Another option identified in the last decade (following trials of similar technology in aircraft combustion engines) is water injection, which suppresses knocking largely by reducing local in-cylinder mixture temperatures due to its latent heat of vaporization. Addition of adequate water can lead to stoichiometric air/fuel ratio engine operation, and hence both reduction in fuel consumption and full utilization of a three-way catalytic converter (TWC).</div><div class="htmlview paragraph">Further information about effects of various water injection parameters is required. Thus, in this study, a 4-stroke, 1.5 liter, 3-cylinder turbocharged engine with direct fuel injection and port water injection was operated on 91, 95 and 98 RON gasoline fuel to assess effects of water injection on knock mitigation, combustion phasing, required air:fuel ratios and exhaust gas temperature control. Full- and part-load curves obtained with different fuels and water injection strategies are presented and discussed.</div></div>

Variation Ignition Timing Against Environmentally Friendly Gas Exhaust Emissions on 7K Gasoline Engine and Its Dissemination Using Website

The purpose of this research is to know the exhaust emissions generated due to changes in ignition and type of fuel. And expected to get various advantages, among others, in terms of environmentally friendly and health terms. In this research is to test directly by using tools that have been provided with mancatat data obtained from the test results and make observations. The results that can be in carrying out this research are the results of different exhaust emissions. However, the results of the study of exhaust emissions generated pertamax (Gasoline RON 92) fuel is less than the emissions of gas produced in gasoline RON 88, ranging from 1% - 3%. The results of this research will be disseminated using the website.

EMISSION OF POLYCYCLIC AROMATIC HYDROCARBONS CONTAINED IN COMBUSTION PRODUCTS OF GASOLINE ENGINES

The concentration of 16 polycyclic aromatic hydrocarbons (PAHs) in the gasoline combustion products emitted into the atmosphere by internal combustion engines (ICE) has been measured using the gas chromatography method. The concentrations of PAHs in the exhaust gases sampled behind a catalytic converter has been determined when the ICE operates in five modes: idle mode, high speed mode, load mode, ICE cold start mode (engine warm-up) and transient mode. Using 92 RON, 95 RON and 98 RON gasoline the effect of the octane number of gasoline on the PAHs content in the exhaust gases has been revealed. The concentration of the most carcinogenic component (benzo(α)pyrene) in the exhaust gases behind a catalytic converter significantly exceeds a reference value of benzo(α)pyrene in the atmospheric air established by the WHO and the EU for ICE in the load mode.

Novel method of dual fiber Bragg gratings integrated in fiber ring laser for biochemical sensors

Optical sensors have been shown to be very effective for measuring the toxic content in liquid and air environments. Optical sensors, which operate based on the wavelength shift of the optical signals, require an expensive spectrometer. In this paper, we propose a new configuration of the optical sensor device for measuring wavelength shift without using a spectrometer. This configuration has a large potential for application in biochemical sensing techniques, and comes with a low cost. This configuration uses dual fiber Bragg gratings (FBGs) integrated in a fiber ring laser structure of erbium-doped fiber, in which one FBG is used as a reference to sweep over the applicable spectrum of the etched-Bragg grating. The etched-FBG as a sensing probe is suitable for bio- and/or chemical sensors. The sensitivity and accuracy of the sensor system can be improved by the narrow linewidth of emission spectra from the laser, the best limit of detection of this sensor is 1.5 × 10−4 RIU (RIU: refractive index unit), as achieved by the optical sensor using a high resolution spectrometer. This sensor system has been experimentally investigated to detect different types of organic compounds, gasoline, mixing ratios of organic solvents in gasoline, and nitrate concentration in water samples. The experimental results show that this sensing method could determine different mixing ratios of organic solvents with good repeatability, high accuracy, and rapid response: e.g. for ethanol and/or methanol in gasoline RON 92 (RON: research octane number) of 0%–14% v/v, and nitrate in water samples at a low concentration range of 0–50 ppm. These results suggest that the proposed configuration can construct low-cost and accurate biochemical sensors.

Absorption of gasoline vapors in automobile adsorber with a carbon filter

Modification of the component composition of gasoline, associated with the use of spirits and ethers (oxygenates) in modern fuels, as well as an increased content of combustible aromatic hydrocarbons may influence the dynamic activity of the coal filter. Therefore, the absorption of gasoline vapors with activated carbon (a coal filter) has been studied. The subjects of the study were samples of gasoline RON 95, RON 98, purchased at different times at gas stations in Russia and Spain. To carry out the tests a carbon filter (activated carbon) of the adsorber of the CITROEN C4 was used. Before filling the sorbent in a dynamic tube, it was regenerated, consisted of heating the coal to temperatures of 250 ... 3000С and forcing it to shake through the container with air material. Experiments on the absorption of gasoline vapors were carried out on a plant consisting of a rotameter, a Drexler bottle, a pressure stabilizer, and a dynamic tube. It has been established that, unlike other samples, two fuel samples have certain features that manifest themselves, in particular, in the values of the boiling temperature, in the value of the octane number, in the acidity parameters and in the remainder in the flask. Activated carbon has a higher adsorption and retention capacity with respect to the components of these gasolines. It is shown that this ability is a reflection of the increased content in the fuel of organic compounds with a higher molecular mass. Such substances include aromatic hydrocarbons and series of compounds containing polar substituents, for example methyl tert-butyl ether.

PPC Operation with Low RON Gasoline Fuel. A Study on Load Range on a Euro 6 Light Duty Diesel Engine

Gasoline Partially Premixed Combustion (PPC) is a promising alternative combustion concept that can offer both high indicated efficiency and low exhaust emissions in terms of NOx and soot, compared to conventional diesel combustion (CDC). Previous research has shown that PPC can operate with gasoline-like fuels of varying RON numbers. Some of the most promising results come with the use of gasoline of low octane number, around RON 70. In this study, a commercially available; 2 litre Euro 6 light duty diesel engine is being operated under various load and speed conditions with the use of RON 75 gasoline. The aim is to evaluate the ability of the engine to operate under PPC conditions with the use of as much OEM hardware installed as possible, in this case a double stage turbocharger. High amount of EGR, approximately 30%, is used in order to control NOx production and combustion reaction rates, together with a double injection strategy, which is beneficial at controlling the pressure rise rate and enable high load operation. The engine is operated at three different RPM levels, 1200-1800-2400 and between 2 to 16 bar IMEPg. Results show that combustion instability poses the limit at the low load while low oxygen content restricts the high load operation. Due to the premixed type of combustion, a fast combustion event is possible, giving a higher effective expansion ratio, which improves the indicated efficiency to levels higher than CDC, while indicated emissions are comparable to CDC operation. (Less)

Flash boiling in a multihole G-DI injector – Effects of the fuel distillation curve

The effects of fuel temperature and chamber pressure on the spray of a multi-hole G-DI injector were analyzed in a quiescent test chamber. The analysis was focused on the behavior of the global spray angles both close and far from the injector. Three pure hydrocarbons (n-hexane, n-heptane, and isooctane), three gasolines of known distillation curve and a commercial 95 RON gasoline from a gas station were utilized. The tests were performed at four chamber pressures (atmospheric, 80kPa, 60kPa and 40kPa) and the fuel temperature was varied from 30°C to 110°C.The results for n-hexane and gasolines were very similar, while n-heptane and isooctane showed a different behavior. The ratio between the fuel saturation pressure at the operating temperature and the air pressure (ps/pa) is confirmed as a fundamental parameter for spray angle data reduction. The near field spray angle data for pure hydrocarbon fuels merge to a unique curve when plotted in function of ps/pa. An approximated method to deduce the gasoline saturation pressure curves starting from the distillation curve is presented. Using the calculated saturation pressures for the reduction of near field spray angle data for the gasolines, a unique curve is obtained, coincident with that of the tested pure hydrocarbons. In alternative, from the results obtained for a fuel of known saturation pressure curve, it is possible to obtain a direct correlation between near field spray angle and saturation pressure. From this relationship, an approximated saturation pressure curve from the experimental angle measurements obtained on the same injector for an unknown fuel can be derived.