Maximum Engine Power Research Articles

Investigation of the effects of camelina sativa biodiesel and eurodiesel blends on vehicle performance and emissions

Studies have been conducted on improving engine performance, reducing environmental pollution caused by vehicles, and using alternative fuels. In the study, tests are carried out in a laboratory environment to check whether the engine has reached the intended use. Testing of internal combustion engines is crucial to research and teaching, trade and environmental pollution. Depending on the purpose of the test, the type and duration of vehicle tests will vary. Automobile manufacturing companies and research units will conduct a series of scientific and long-term tests in the vehicle development process. Thanks to engine and vehicle tests under different operating conditions, the measured values such as economy, power, moment, emission are compared with performance curves. In this study, biodiesel was obtained from crude camelina sativa oil using the transesterification method. Camelina sativa biodiesel was mixed with Eurodiesel at the rate of 7% (B7), 20% (B20) and 50% (B50). Vehicle performance measurements of biodiesel-Eurodiesel blends were made on a vehicle with four-stroke, four-cylinder, Common-rail fuel system, turbocharged and water-cooled engine using a chassis dynamometer. Vehicle performance and exhaust emissions were measured at different speeds during the vehicle chassis dynamometer test. While the highest moment value was obtained at 80 km/h in B7 fuel, the maximum engine power was obtained in B7 fuel at 160 km/h. Average engine power and maximum engine torque of B100 fuel decreased by 3,28% and 10,21% compared to Eurodiesel fuel. As the rate of biodiesel increased, specific fuel consumption increased. The highest specific fuel consumption was obtained with 91,6 g/kWh in B100 fuel at 160 km/h. The average specific fuel consumption of B100 fuel increased 38,5% compared to Eurodiesel fuel.When we look at the results of exhaust emission measurements, it is seen that camelina sativa biodiesel and fuel mixture decreased CO, CO2 and HC values compared to Eurodiesel fuel, but increased NOx values.

Effect of performance generator set 1.5 PK 4 stroke with variations in load and type of spark plugs

Energy is one of the most important needs for humans, and electricity is one of the energy needs needed to support various human activities both day and night. One source of electrical energy is obtained by using a generator as a power plant. The generator set is used as a backup when the electricity supply from PLN is cut off.Efforts to get a good performance generator set are made by improving the combustion quality to increase efficiency. Tests carried out on a four-stroke one cylinder generator capacity of 1.5 PK with variations in load and type of spark plugs are standard, platinum, and iridium, which at 3000 rpm engine speed with a load of 350, 700 and 1050 Watt pertalite fuel with a volume of 10 ml. The value of Torque and power has increased along with the increased engine load. The optimum generator performance is obtained at a load of 700 watts when using this type of platinum spark plug. The maximum engine power generated is 1,092 HP. Torque of 2.59 Nm and the lowest fuel consumption (SFC) of 0.484 kg/hp.hour.

Покращення тягового-швидкісних властивостей вдосконаленням методів вибору параметрів моторно-трансмісійної установки автомобіля

Aerodynamic characteristics have a major impact on the energy efficiency and traction and speed properties of the vehicle. In this article, based on previous studies of the aerodynamic characteristics of various car models, we propose an improved method for selecting engine and transmission parameters at the design stage. The aim of the study is to improve the dynamic properties of the car by improving the method of selecting the main parameters of the engine-transmission unit by refining the calculation of aerodynamic drag. To achieve it, the following tasks must be solved: to specify the method of selecting the maximum effective engine power; to specify a technique of definition of the maximum constructive speed of the car; to develop a technique for selecting gear ratios. The aerodynamic resistance to the movement of the vehicle is determined by the frontal coefficient of the specified resistance, the density of the air, the area of the frontal resistance and the speed of the vehicle. It is known from classical works on the aerodynamics of a car that in the range of vehicle speeds from 20 m / s to 80 m / s, taking the law of squares when assessing the force of air resistance, it is necessary to change the coefficient of frontal aerodynamic drag depending on the speed of the car. However, when carrying out calculations, this coefficient is taken constant, which leads to obtaining large values of the air resistance force at high speeds and lower at low speeds. There are two possible ways to improve the dynamic properties and energy efficiency of the car during its modernization (increasing the maximum design speed of the car by reducing the gear ratio in higher gear; reducing the maximum efficiency of the engine while maintaining the previous gear ratio in higher gear). As a result of the study, the method of selection (maximum effective engine power; maximum design speed of the car; gear ratios) at the design stage of the parameters of the motor-transmission unit of the car has been improved.

Coating of diesel engine with new generation ceramic material to improve combustion and performance

In this study, piston and valve surfaces of a Diesel engine to improve exhaust emis?sion and engine performance values, NiCr with bond coat and without bond coat with Cr2O3, Al2O3+13%TiO2, Cr2O3+25%Al2O3 coatings were coated using plasma spray method. By examining the micro-structures of the coating materials, it was observed that a good coating bond is formed. In this study, unlike other coating applications, two different and proportions of specific ceramic powders were coated on the combustion chamber elements, mounted on a Diesel engine, and their effects on engine performance and emissions were tested on the engine dynamometer. For this purpose, the internal combustion engine was operated at 1400, 1700, 2000, 2300, 2600, 2900, and 3200 rpm engine speeds and engine power, engine torque, in-cylinder pressure changes and heat release rate values were recorded. In this study, the that results were obtained by comparing thermal barrier coated engine with standard engine. An increase of 14.92% in maximum engine power, 12.35% in engine torque, 13% in-cylinder pressure, heat release rate by 4.5%, and brake thermal efficiency by 10.17% was detected, while brake specific fuel consumption decreased by 14.96%.

Experimental evaluation of piston motion modification to improve the thermodynamic power output of a low temperature gamma Stirling engine

Stirling engines are a variety of heat engines which are capable of using heat from various sources including low temperature renewables. This work examines performance of a lab scale low temperature gamma type Stirling engine with a drive train modified with oval elliptical gears. The gears were added to dwell the engine piston motion to attempt to improve the thermodynamic performance of the engine by better replicating the ideal Stirling cycle. A variety of dwelling piston configurations were tested on both the displacer and power piston. It was observed that that the piston dwelling had the anticipated effect of changing the engine indicator diagrams to more closely resemble the ideal cycle, however there were no substantial improvements to maximum engine power. It was observed that dwelling the displacer piston caused substantial reductions to engine running speeds and resulted in maximum power being reduced. In the case of power piston dwelling the indicator diagram was enlarged and there were slight increases to maximum power production. Overall the added complexity of dwelled piston motion systems is not likely an advantageous method of increasing the power output of low temperature difference Stirling engines.

Investigation of energy losses in hydraulic shock absorbers of the BTR-4 armored personnel carrier suspension and assessment of the feasibility of using its recovery system

Investigations of energy losses in hydraulic shock absorbers (HSA) of the BTR-4 armored personnel carrier while driving along three sections of unpaved roads and rough terrain, which met light, moderate and heavy road conditions, are presented. The speed range that was considered (20...64 km/h) covered the pre-resonant, resonant and non-resonant modes of motion. The studies were carried out by a numerical experiment using an experimentally verified mathematical model of the motion of a military wheeled vehicle along roughnesses, which was implemented in the DELPHI environment. The power was calculated, the HSA of the suspension of each wheel were absorbed, the instantaneous maximum values of these powers and the maximum vertical accelerations at the driver's seat and at the center, indicating the efficiency of the HSA and the level of ensuring the necessary smoothness. The total maximum power absorbed by the HSA of all suspensions, depending on the speed and road conditions, amounted to 2,1...19,5 kW or 0,57 ... 5,3 % of the maximum engine power, which indicates significant losses energy in the suspension vehicle BTR-4 and the feasibility of using its recovery system. HSAs of 1 suspension, which absorbed power from 1,2 kW (light road conditions, pre-resonance mode), 7,6 kW (heavy road conditions, resonance mode) and up to 6,8 kW (heavy road conditions, out-of-resonance mode), were the most loaded in all road conditions and driving modes, which amounted to 57,14 %, 42,22 % and 34,87 % of the total power, which was absorbed by the HSA of all suspensions. Thus, the energy recovery system can be used only on 1 suspension, since it is on them that on average accounts for half the energy that is absorbed by all HSAs. This will reduce the cost of this system, its weight and increase the reliability and performance of the suspension as a whole. Even taking into account the efficiency, such a recovery system will allow producing an amount of energy comparable to the energy of a regular brand 6301.3701 generator with a rated power of 4,2 kW. Studies have shown that the required smoothness of travel (maximum vertical accelerations at the driver’s place and, in particular, less than 3 g) in the entire speed range is provided only when driving in light road conditions, and, with the exception of the resonance mode (37,2...46,7 km/h) when driving in moderate traffic conditions. When driving in difficult road conditions, the required ride smoothness is not provided in the entire speed range, which indicates the need for a significant improvement of the BTR-4 suspension, including a significant, several-fold increase in the power absorbed by the HSA. In this case, the efficiency of the recovery system will also significantly increase, which, in turn, will solve another acute problem, namely, overheating and failure of the HSA. As a result of the studies carried out using the BTR-4 armored personnel carrier as an example, the feasibility of developing and using an energy recovery system of one type or another in the suspension of a military wheeled vehicle is substantiated, which, provided the suspension is comprehensively improved, can return up to 15...20 % of maximum power for future use engine. This will significantly improve such indicators of mobility as dynamism, smoothness and autonomy (power reserve), which is especially important in the case of using a hybrid power plant and electric transmission.

Mechanical Devices for Mass Distribution Adjustment: Are They Really Convenient?

Since the introduction of four-wheel drive (4WD) and especially front wheel assist (FWA), many studies have been conducted on the optimal weight distribution between tractor front and rear axles because this influences traction efficiency. The aim of this paper is to evaluate the traction and efficiency advantages in the adoption of mechanical ballast position adjustment devices. The tested device is an extendable ballast holder mounted on the front three-point hitch of the tractor, able to displace the ballast up to 1 m away from its original position. An estimation of the fuel consumption during ploughing with the extendable ballast holder in different configurations was performed. Tractive performance was evaluated through drawbar tests, performed on loam soil with a 4WD tractor having a maximum engine power of 191 kW and a ballasted mass of 9590 kg. Results show that changing the tractor weight distribution over the range allowed by the extendable ballast holder produces limited effects in terms of tractive performance and fuel saving. The adoption of such devices is thus ineffective if other fundamental factors such as tyre pressure, choice of the front-to-rear wheel combination and lead of the front wheels are not considered during tractor setup.

Thermodynamic analysis of a gamma-type stirling engine driven by Scotch Yoke mechanism

ABSTRACT In this study, thermodynamic analysis of a gamma-type Stirling engine driven by Scotch Yoke mechanism was conducted. The advantages of Scotch Yoke mechanism over classical crank mechanism were discussed in detail. In the analysis hydrogen was used as working gas. Working space was divided into 16 nodal volumes. Solution of conservation of mass and energy equation were obtained for each nodal volume. Wall temperatures of nodal volumes were assumed to be constant and temperature variations in nodal volumes were calculated by means of the first law of the thermodynamics. Maximum engine power was obtained as 1105 W at 800 rpm engine speed and gas mass of 0.3 g for 1200 W/m2K heat transfer coefficient. The optimum phase angle, which was not affected significantly by hot end temperature, gas mass, and heat transfer coefficient variations, was determined as 90° degrees at engine speed of 600 rpm. However, it was determined that engine speed has a great impact on optimum phase angle and a variable phase angle mechanism may be useful to obtain maximum specific power from the engine at different engine speeds. At engine speed of 600 rpm, the maximum specific power of the engine was 695 W/l for 1.65 compression ratio and 90° degrees phase angle.

Efficiency at Maximum Power of the Low-Dissipation Hybrid Electrochemical–Otto Cycle

A novel analytical method was developed for analysis of efficiency at maximum power of a hybrid cycle combining electrochemical and Otto engines. The analysis is based on the low-dissipation model, which relates energy dissipation with energy transfer rate. Efficiency at maximum power of a hybrid engine operating between two reservoirs of chemical potentials is evaluated. The engine is composed of an electrochemical device that transforms chemical potential to electrical work of an Otto engine that uses the heat generated in the electrochemical device and its exhaust effluent for mechanical work production. The results show that efficiency at maximum power of the hybrid cycle is identical to the efficiency at maximum power of an electrochemical engine alone; however, the power is the product of the electrochemical engine power and the compression ratio of the Otto engine. Partial mass transition by the electrochemical device from the high to the low chemical potential is also examined. In the latter case, heat is generated both in the electrochemical device and the Otto engine, and the efficiency at maximum power is a function of the compression ratio. An analysis performed using the developed method shows, for the first time, that, in terms of a maximal power, at some conditions, Otto cycle can provide better performance that the hybrid cycle. On the other hand, an efficiency comparison at maximum power with the separate Otto-cycle and chemical engine results in some advantages of the hybrid cycle.

The effect of hydrogen addition to Cynara biodiesel on engine performance and emissions in diesel engine

ABSTRACT This paper aims at studying, the effects of biodiesel-diesel, biodiesel-hydrogen, and diesel-hydrogen fuel blends on engine performance, emissions, and combustion characteristics were investigated in a modified 4-cylinder, turbocharged, common rail direct injection, and compression ignition (CI) engine. Biodiesel was produced from through transesterification of Cynara cardunculus seed oil according to EN 14214 standards with a short-chain alcohol in the presence of a catalyst. The addition of hydrogen as a combustion enhancer used to counteract the increase in emissions and further improve engine performance. Hydrogen was injected in small quantities in the air intake manifold, while diesel-biodiesel blends were injected directly inside the cylinder. Diesel (D), biodiesel (B100), and biodiesel-diesel-hydrogen (B7+H2.5), biodiesel-hydrogen (B100+H2.5), and diesel-hydrogen (D+H2.5) fuel blends were used. Experimental results showed that while maximum engine power and maximum engine torque were obtained with B7+H2.5, the highest thermal efficiency was achieved with B100+H2.5. The lowest specific fuel consumption was obtained as 217 g/kWh at 2000 rpm with diesel. Maximum cylinder pressure and heat release rates were measured as 100.48 bar and 576.12 kJ/m3 deg with diesel fuel at 3000 rpm. The minimum CO emissions were obtained as 0.04% with B100 and B100+H2.5 fuels. CO2 and HC emissions reduced significantly whereas NOx increased, compared to diesel fuel.

Experimental Analysis of a Laboratory-Scale Diesel Engine Exhaust Heat-Driven Absorption Refrigeration System as a Model for Naval Surface Ship Applications

Decreasing industrial energy sources and major environmental problems caused by uncontrolled energy consumption have led to studies on alternative energy sources. This study presents a design and experimental analysis of an exhaust gas-driven absorption refrigeration system for the purpose of air conditioning by using the exhaust heat of a diesel engine, which is installed in the Naval Academy Mechanics Laboratory. The diesel engine is loaded with a dynamometer, and water and ammonia are used as an absorbent and refrigerant, respectively. At various diesel engine loads, cooling capacity and coefficient of performance (COP) of the absorption refrigeration system are calculated. Experimental results have indicated the cooling capacity as 1.098 kW at a maximum engine power of 4.9 HP. The highest COP value in the designed system has been calculated to be .3022 for the generator temperature of 160 C. Although the COP of refrigeration is low, the absorption refrigeration system can be provided a great cooling load from the exhaust heat of diesel engines and can be used in naval surface ships. In addition to energy efficiency of naval surface ships, infrared and acoustic signature can be minimized and a ships susceptibility can be dramatically reduced.

Determination of the required power for bus hybrid engine

This article presents a methodology for determining the required engine power of hybrid city buses. The vehicle’s driving cycle and its main technical characteristics were used as the initial data. The calculated change in power on the driving wheels is an intermediate result and is used to analyze the chains of energy transfer from gasoline engine to driving wheels. In this approach, a sequential type of circuit in a hybrid drive is used. A bus weighing 4 tons was considered as an example, and the calculations showed that the maximum power of the internal combustion engine should be 15.2 kW.

ОЦІНЮВАННЯ СТІЙКОСТІ РОБОТИ АВТОМОБІЛЬНОГО ДВИГУНА ЗА УМОВИ ПОСТІЙНОЇ КУТОВОЇ ШВИДКОСТІ КОЛІНЧАСТОГО ВАЛА

The operation of the automobile engine at a constant angular speed of the crankshaft at an unsteady mode of movement of the car allows increasing its energy and fuel efficiency. It is necessary to use a continuously variable transmission, which allows you to change the speed of the vehicle with infinitely variable gear ratio change transmission without acceleration of the rotating masses of the engine. With a continuously variable automatic change gear ratio of the transmission, it is possible to realize engine operating modes that provide maximum effective engine power, maximum effective engine torque, and also minimum effective specific fuel consumption. It should be noted, that even with perfect management continuously variable transmission fails to obtain the constant value of the angular velocity of the crankshaft, as the internal combustion engine generates oscillations of the indicator torque. As a result of the study, an assessment of the possibility of maintaining a constant angular velocity of the crankshaft at steady and unsteady vehicle motion modes was made. The possibility of transmission operation in the pre-resonance and non-resonance frequency regions has been taken into account. A method has been developed for assessing the stability of an automobile engine with uneven effective torque of an internal combustion engine and a continuously variable transmission. The calculated dependencies are obtained, taking into account the elastic-inertial properties of the transmission and the coefficient of unevenness of the engine's torque, allowing determining the maximum deviations of the angular velocity of the crankshaft in the considered vehicle motion modes. It is shown, that the operation of the transmission in the near- resonance zone not only leads to additional cyclic loads on the parts and components of the transmission itself, but also reduces the energy efficiency of the vehicle power plant. Recommendations to improve the performance of motor-transmission units are formulated.

Predictive Cylinder Deactivation Control for Large Displacement Automotive Engines

This paper presents a self-learning strategy to control the deactivation of cylinders in large displacement automotive engines. Cylinder deactivation is a useful strategy to reduce emissions and improve fuel consumption without limiting the maximum engine power. A cylinder deactivation algorithm has to balance the target of reducing emissions with drivability concerns. Changing the cylinder configuration at the wrong time or too often negatively affects drivability and fuel efficiency. The paper proposes a self-learning algorithm inspired by the Markov Chain formalism. The proposed algorithm predicts the future fuel consumption and determines the best cylinder configuration based on that prediction. The prediction algorithm is learnt online using past inputs and thus adapts to the specific driver and conditions. Two versions of the algorithm are proposed that use two different inputs. The approaches are validated in simulation on an engine test-bed, showing that the self-learning algorithm yields fuel savings up to 10% without affecting drivability in the New European Driving Cycle.

An updated methodology to analyse the idling of agricultural tractors

Idling is a status of tractors in which the engine is not subjected to any substantial load and the vehicle is stationary. Idling is detrimental for the environment and health of people and it is a frequent status for agricultural tractors. Indeed, agricultural tractors may idle from 10 to 43% of their entire operating time. Only in some conditions idling is necessary (e.g. implement hitching), otherwise it is a condition which wastes fuel. The aim of this paper is to report on an updated methodology to analyse the idling practice of agricultural tractors. Idling was monitored through a dash-cam and a CAN-Bus data logger installed on a tractor with a maximum engine power of 191 kW. The tractor ran on idle for 17% of its entire operating time with the most frequent stops occurring for the adjustment of the implement when the soil engaging tools become clogged by crop residuals. Moreover, during 67% of the idling duration, no tractor subsystem was used, so most of the idling was not caused by a real need. This idling was responsible for a waste of 1.6% of the fuel used. Considering that in Italy 8.3% of the tractors belong to the same class (in terms of mass) of that used in this study, 43 million of litres of fuel are supposed to be wasted per year. The results of this study could be used for developing anti-idling devices on agricultural tractors.

Influence of varying altitudes on matching characteristics of the Twin-VGT system with a diesel engine and performance based on analysis of available exhaust energy

A variable geometry turbocharger in series with a variable geometry turbocharger (Twin-VGT) system was designed to improve engine power at high altitudes. The influence of altitudes on the performance of the Twin-VGT system was investigated in the perspective of available exhaust energy. The interaction between exhaust flow characteristics of Twin-VGT and openings of Twin-VGT vanes was theoretically analyzed at different altitudes. Meanwhile, a model of a diesel engine matched with the Twin-VGT system was built to study the matching performance of the Twin-VGT system with engine at different altitudes. The optimal opening maps of both high-pressure and low-pressure VGT vanes at high altitudes were obtained to achieve the maximum engine power. The results showed that the optimal openings of high-pressure and low-pressure VGT vanes decreased with increase in altitudes. The operating points of the two-stage compressors located at the high efficiency region and the compressor efficiency region both exceeded 62% at different altitudes. The global expansion ratio increased with increase in altitudes and reached 4.9 at 5500 m. Compared with the VGT in series with a fixed geometry turbocharger on testing bed, exhaust energy of Twin-VGT turbines at low speeds was utilized reasonably and global pressure ratio increased by 0.69–0.94, while brake-specific fuel consumption decreased by 11.24–33.62% under low speeds above altitudes of 2500 m.

Effect of nano-additives blended diesel-biodiesel on performance and emissions of CI engine in the presence of magnetic field

ABSTRACTIn the present study, biodiesel produced from waste cooking oil was added to the diesel fuel at various volume percentages. Nanoparticles of cobalt oxide and cerium oxide were also used as additive to diesel-biodiesel blends. The fuel was magnetized by two neodymium magnets with grade of 42. The effect of six parameters including the magnetic field, biodiesel percent, nano-additives concentration, nano-additives ratio (CeO2 to Co3O4), engine speed, and engine load were evaluated using the Box-Behnken experiment design and RSM method. Optimization of performance parameters and engine emissions showed that the best conditions involved the magnetic field of 1,561.66 Gauss, nano-additives concentration of 12.26 ppm, nano-additives ratio of 56.37%, biodiesel volume fraction of 4.98 vol%, engine speed of 1,962 rpm and engine load of 66.14%. Under these conditions, the engine performance and emissions were as follows: maximum engine torque of 14.67 ± 0.73 Nm, maximum engine power of 3.36 ± 0.14 kW, minimum brake special fuel consumption (BSFC) of 272.50 ± 140.77 gr/kW.h, minimum carbon monoxide (CO) emission of 0.136 ± 0.086 vol%, minimum carbon dioxide (CO2) emission of 0.027 ± 0.28 vol%, minimum-unburned hydrocarbons (UHC) of 0.032 ± 48.12 ppm and minimum nitrogen oxide (NOx) of 4 ± 13.78 ppm with the desirability of 0.89.

Investigation of factors affecting the gaseous and particulate matter emissions from diesel vehicles

This study presents a detailed investigation of diesel vehicle emissions utilizing chassis dynamometer testing. The recruited vehicle fleet consists of 15 in-use diesel vehicles, spanning a wide range of emission standards, engine sizes, weight, model year, etc. The real-time emission concentrations of nitrogen oxides (NOx), total hydrocarbons (THC), carbon monoxide (CO) and carbon dioxide (CO2), and the mass of particulate matter (PM) collected on filters are measured and used to calculate the vehicle emission factors (EFs) under various driving conditions. Results show that in general EFs of NOx, CO, THC, and PM of the recruited fleet span a wide range of values (NOx 0.80 ± 0.34 to 60.28 ± 2.94 g kg−1; THC 0.10 ± 0.04 to 5.28 ± 1.28 g kg−1; CO below detection limits to 24.01 ± 8.48 g kg−1; PM below detection limits to 2.47 ± 1.22 g kg−1). Further data analysis shows that the implementation of a higher emission standard has a significant effect on reducing the emission of pollutants, except for NOx. Driving conditions are also important factors affecting the EFs. Besides, statistical analysis shows a significant correlation between EFs of NOx with the testing weight and the maximum engine power of the vehicle. Further investigation is recommended to explore the effect of maintenance of the vehicles to the vehicular emission.

Experimental studies on the biodiesel production parameters optimization of sunflower and soybean oil mixture and DI engine combustion, performance, and emission analysis fueled with diesel/biodiesel blends

The influence of diesel/biodiesel blends on engine combustion, performance, and exhaust gas emissions have carried out experimentally at different engine loads and constant speed of 1400 rpm. Volumetric percentage of diesel/biodiesel blends: D70B30 (70% diesel−30% biodiesel), D50B50 (50% diesel−50% biodiesel) and D30B70 (30% diesel−70% biodiesel) were prepared to power a single cylinder diesel engine. The engine results as compared to diesel fuel, show a reduction in the rate of change of CO by 33.8% for D50B50. The slight decrease in maximum cylinder pressure for higher percentage of biodiesel blends due to low calorific value of biodiesel and lower ignition delay. The reduction in HRR for biodiesel blends as compared to diesel fuel. HRR was about 31.7, 52.4 and 63.5 (J/deg) for 10%, 30% and 60% of maximum engine power. The highest reduction in HC emissions concerning diesel fuel was about 4.18% for D30B70. NOx emissions of biodiesel blends were higher than diesel. Exhaust oxygen (EO) emissions for D30B70 was about 0.98% higher than diesel. Exhaust gas temperature (EGT) has observed for all biodiesel blends. Brake specific fuel consumption (BSFC) is increased until it reaches 11.43% for D30B70. A consequent reduction in brake thermal efficiency (BTE) and brake specific energy consumption (BSEC) is observed for all biodiesel blends.

Development of offers on application of additional jet impact on the fixed pitch propeller for the purpose of rational use of the power of the main engine

The choice of the design operational points of the main engine to achieve the design speed of the ship determines the efficiency of the propulsion plant. At the same time, the limits recommended by the engine manufacturer for selecting the design operational points do not fully take into account current trends and can be changed. The problem of the rational use of the nominal power and specified maximum continuous rating power of the main engine operating on a fixed pitch propeller is relevant.