687results about "Internal-combustion engine testing" patented technology

The invention relates to the technical field of fault detection, and discloses a diesel generating set fault detection method and system based on deep learning, and the method comprises the steps: obtaining first vibration signal data, and carrying out the time-frequency decomposition, and obtaining a dynamic change feature; de-noising processing is carried out on the dynamic change features to obtain a time-frequency feature sequence; extracting a peak energy distribution data set, and calculating each frequency band entropy value to obtain a frequency band entropy value sequence; classifying the frequency band entropy sequence, determining a random fluctuation reference mode, and separating to obtain an abnormal frequency component; calculating a spectral line spacing and amplitude ratio, obtaining a spectral line feature data set, classifying the spectral line feature data set, and determining a fault classification result; obtaining current second vibration signal data, performing similarity calculation on the current second vibration signal data and a pre-established normal mode library, and outputting a fault feature vector; and verifying the fault feature vector to obtain a final fault detection result. According to the method, closed-loop diagnosis from signal acquisition to fault classification can be realized, and the fault detection precision of the diesel generating set is improved.

The invention discloses a digital twin intelligent test run system based on a marine medium-speed diesel engine and a monitoring method, relates to the technical field of monitoring, and is used for solving the problems of degeneration identification lag and low emission early warning precision of an oil injector. The system comprises a multi-source heterogeneous data preprocessing module and a running state intelligent diagnosis module. The multi-dimensional data acquisition module is used for acquiring in-cylinder pressure, crankshaft torsional vibration and transient air-fuel ratio signals to construct multi-dimensional data vectors, and the multi-dimensional data acquisition module is used for analyzing combustion fluctuation characteristics based on an attention mechanism LSTM (Long Short Term Memory) network, identifying early deterioration of an oil injector and outputting an oil injection consistency coefficient and a fault type identifier. The method comprises the steps that according to an oil injection consistency coefficient, electromagnetic valve response delay and combustion parameter correlation are tracked, a degradation trend is predicted, and emission early warning is generated; and according to prediction and early warning results, fuel injection compensation parameters are dynamically adjusted in the digital twinborn model, a recursive least square method is adopted to identify combustion parameters and feed the combustion parameters back to an electric control unit, and self-adaptive optimization and closed-loop control in the test run stage are achieved.

The invention discloses an engine fault diagnosis method, device and equipment and a storage medium, and relates to the technical field of fault diagnosis. The method comprises the following steps: synchronously acquiring a sound signal and a vibration signal of an engine in a normal operation state, and performing feature extraction on the sound signal and the vibration signal to obtain corresponding target features; the target features comprise time domain features, frequency domain features and time-frequency domain features; determining a statistical index of each target feature through statistical characteristic analysis, and performing feature fusion on all the target features according to a target fusion mode based on the statistical indexes to obtain a fusion index; and an early warning threshold value is determined according to the data statistical characteristics of the fusion index, so that fault monitoring is carried out on the engine by using the early warning threshold value. Fault diagnosis is carried out according to the early warning threshold value determined according to the sound vibration data of the engine in the normal operation state, high dependence on fault samples is avoided, and the comprehensiveness of fault analysis is improved.

Disclosed are an apparatus for a simulation test of diesel engine fuel spray in an alpine environment and a test method, the apparatus comprising a fuel storage and pretreatment device, a fuel injection system, an optical visualization system, an environment chamber, and a spray pretreatment system. In alpine environmental conditions, the apparatus can achieve high-pressure injection of liquid, separate injected atomized mist into fine droplets and impinge same on a wall surface by means of a multi-droplet generation apparatus and a wall surface apparatus, and observe and record the whole process by means of an optical visualization path. According to the present invention, the problem of difficulty in distinguishing droplets due to the coalescence of spray into a sheet is avoided, the costs of a traditional spray and droplet test solution can be significantly reduced, and the problem of a high level of dependence on a control program in a constant volume vessel solution is solved. According to the present invention, simulation of spray test in an alpine environment is possible, and the test apparatus has a simple structure. Moreover, it is possible to conduct regular research on free spray, multi-droplet wall impingement, spray wall impingement, and development characteristics thereof under conditions such as different altitudes and different temperatures.

An ignition diagnostic system and method for evaluating and optimizing the ignition performance of internal combustion engines (ICEs), such as those that burn hydrogen (H2) and / or other fuels. According to one example, the ignition diagnostic system and method use an artificial intelligence (AI) model with one or more machine learning (ML) algorithm(s) to identify, predict and / or otherwise evaluate abnormal combustion events, and to provide such information to an electronic control unit (ECU) in real-time. The ECU, in turn, can make combustion-related modifications to one or more components of the ignition system to optimize performance. By integrating the AI model into the ignition diagnostic system and method, a fast and simplified solution is provided that can be implemented across a wide variety of ICEs, including those that burn alternative fuels, where detecting abnormal combustion events and monitoring combustion-related parameters can be important.

The invention discloses a service life prediction method of an automobile shock absorber, and relates to the technical field of service life evaluation. The method comprises the steps that the engine speed, the torsional amplitude value, the engine oil temperature and the load torque are collected, and an engine parameter set is formed after preprocessing; standard parameters of engines of the same model are collected, a frequency spectrum peak value is obtained by processing torsional amplitude values in a parameter set, and the resonance frequency of the engines is calculated by combining the standard parameters; constructing a damper operation state threshold model based on an STL time sequence decomposition method, inputting engine oil temperature and load torque to obtain a threshold, comparing resonant frequency with the threshold, and determining a damper damping state; the torsional vibration change rate is calculated and compared with standard parameters of the same model to obtain the working state of the shock absorber; and constructing a shock absorber life prediction model based on an accumulative damage theory, inputting a damping state, a working state and an engine parameter set, and outputting residual life. According to the method, the multi-dimensional real-time working condition parameters are considered, so that the residual life of the automobile shock absorber is predicted more accurately.

The invention discloses a single-sensing double-blade tip timing vibration speed measurement method, system, medium and equipment, and the method comprises the steps: only installing a blade tip timing sensor in the circumferential direction of a rotor blade case, and obtaining a blade arrival time sequence generated when rotor blades sequentially pass through the blade tip timing sensor; calculating the instantaneous rotating speed of the rotor based on the arrival time intervals of all adjacent rotor blades; the blade tip linear velocity between the two rotor blades is extracted by combining the circumferential included angle and the measuring point radius of any two rotor blades in the blade disc; removing a trend term related to the rotating speed from the blade tip linear velocity to obtain a velocity quantity reflecting the real vibration characteristics of any two rotor blades; a two-degree-of-freedom dynamic model is constructed by combining prior information of a blade Campbell diagram, and double-blade vibration parameter identification is realized by adopting a nonlinear least square fitting method.

The application discloses an outboard motor testing system, which comprises a water tank, a supporting device for supporting the outboard motor above the water tank, two height adjusting mechanisms installed on the supporting frame, a turnover mechanism installed on the height adjusting mechanisms, a crossbeam installed between the two turnover mechanisms, a clamping device arranged in the water tank for clamping and fixing the testing end of the outboard motor, and a dynamometer arranged outside the water tank and connected with the propeller shaft of the outboard motor through a transmission shaft mechanism. The outboard motor testing system can improve the testing precision and efficiency.

The invention provides an engine cylinder cover thermal fatigue virtual test verification method and system, and relates to the technical field of virtual simulation modeling, and the method comprises the steps: obtaining the micro-macro parameter characteristics of an engine cylinder cover; constructing a parameterized model of micro-macro coupling; performing reverse solution on the control parameters of the physical rack based on a target temperature circulation curve set by a user to obtain a boundary condition parameter set required by a virtual test; generating a virtual-real homologous file according to the parameterized model and the boundary condition parameter set; actual measurement temperature data after the physical rack executes the control instruction file and simulation temperature data after the finite element analysis software executes the simulation input file are collected; according to the two-dimensional topological structure of the fire power surface, virtual thermocouple measuring point coordinates are generated; establishing data channel mapping according to the measuring point coordinates of the virtual thermocouple; calculating temperature errors of the plurality of measuring points; when the temperature error exceeds a threshold value, a correction prompt for the measuring point is output; and verifying the parameterized model according to the correction prompt.

The present invention solves the problems associated with a conventional method for determining the deterioration tendency of a rotating machine, namely, intersecting adjustments, low accuracy, reduced speed, and the inability to meet the requirement for a predictive lead value. According to the invention, a method for determining the deterioration tendency of a motor is provided based on failure genes. Based on the failure gene technique, the fundamental causes and characteristics of potential failures are evaluated, and a method for predicting the tendency is deeply integrated with failure models to provide a reference basis for more in-depth prediction of the tendency.According to the invention, two groups of signal processing methods are used to comprehensively capture information about the features in the failure signals in order to improve the ability to detect and evaluate different failure modes. The invention proposes a set of rules for detecting a trend model, comprising a standardized procedure for data collection and processing, a system of key figures for model evaluation and verification, and a strategy for model updating and optimization. This enables more efficient detection and adaptation of the trend model by the system and significantly increases the efficiency and reliability of establishing the trend model.

The application provides a multi-head fan-shaped combustion chamber test piece with a sound-absorbing cavity and a sound-absorbing adjusting method. The test piece comprises a bearing casing between an air inlet pipe and an air outlet pipe; an air inlet assembly arranged in the bearing casing, wherein the air inlet assembly comprises a flow regulation pipe and a diffuser pipe, the flow regulation pipe comprises an inlet baffle and a flow regulation pipe, the diffuser pipe comprises a fixed plate, a flow guide pipe, a flow expansion pipe and a conical wall, the upper and lower ends and the left and right ends of the flow regulation pipe and the diffuser pipe are connected with the bearing casing, a plurality of first acoustic damping holes are formed in the flow regulation pipe, and a plurality of second acoustic damping holes are formed in the conical wall; and a flame tube assembly arranged at an air outlet of the air inlet assembly. The frequency of a first Helmoltz resonator formed by the flow regulation pipe and the bearing casing is the same as the disturbance frequency of the airflow in the air inlet pipe; and the frequency of a second Helmoltz resonator formed by the diffuser pipe and the bearing casing is the same as the combustion oscillation frequency in the flame tube assembly. The application can effectively suppress combustion oscillation, maintain stable airflow and reduce noise.

The invention discloses a three-dimensional pressure field measurement method for spray flame measurement in an optical engine, and belongs to the technical field of optical imaging applied to spray flame measurement in the optical engine. The implementation method comprises the following steps of: establishing a Cartesian coordinate system in the transparent cylinder of the optical engine, and applying a tomographic particle image velocity measurement method to the diagnosis of a spray flow field or a flame combustion process in the transparent cylinder of the optical engine; and calculating first-order derivatives of the three-dimensional velocity field distribution in time and three space directions. And substituting the first-order derivatives of time and space into a Navier Stokes equation to calculate and obtain pressure gradient field distribution in three space directions. And calculating the three-dimensional pressure relative distribution of the whole space to be measured relative to the pressure reference point through a direct integration method. A real pressure value at the pressure reference point is determined through a cylinder pressure sensor in the optical engine, and then three-dimensional pressure field distribution of the whole space to be measured is obtained.

The invention belongs to the technical field of hydrogen-fired aero-engine outfield tests, and provides a hydrogen energy engine mobile test system and method, and the method comprises the steps: carrying out the replacement through employing replacement gas and hydrogen in sequence before starting; carrying out first unsealing by using replacement gas and carrying out second unsealing by using hydrogen, providing hydrogen for the detected hydrogen energy engine to carry out false start detection, and carrying out false start inspection; starting performance debugging is divided into a plurality of debugging sections, the hydrogen supply amount of each debugging section is adjusted, and the tested hydrogen energy engine is subjected to running-in operation from a slow state until the maximum rotating speed is reached; steady-state performance debugging and acceleration and deceleration performance debugging are carried out under the designed working condition, and shutdown is carried out. According to the system and the method, the reliability and the safety of a hydrogen-fired aero-engine debugging test based on the mobile test bed can be guaranteed, and compared with a traditional aero-engine test system, the system and the method have more pertinence on safety protection and method flow design of hydrogen fuel.

The application discloses a kind of automobile engine dynamic prediction monitoring systems, comprising: data acquisition module, data preprocessing module, prediction module, monitoring module;Data acquisition module is used to obtain historical data, running standard data, running measured data;Data preprocessing module is used to process the data collected, is divided into different data sets, and corresponding database is constructed;Prediction module is used to predict whether failure is possible according to convolutional neural network and the data collected.The monitoring module judges whether the engine operation is normal;Display module is used to display the engine operating data, and the data judged as abnormal is marked.The application divides the running standard data and the running measured data obtained according to the engine working condition, and constructs the corresponding comparison database, which only needs to be compared with the data under the corresponding working condition to quickly judge whether a failure occurs and the corresponding fault type.

The invention relates to the technical field of motor vehicle tail gas detection, in particular to a method for detecting tail gas quality through rotating speed detection of a motor vehicle, which comprises the following steps: S1, preparing detection equipment and environmental parameter configuration; s2, instrument self-inspection and gas path cleaning before measurement are carried out; and S3, initializing docking measurement conditions of the exhaust system. Accurate rotating speed monitoring and pollutant concentration determination jointly ensure authenticity and representativeness of tail gas emission data, the pollutant concentration is effectively corrected through subsequent data processing means such as dilution factor and humidity correction, the accuracy of a test result is further improved, and based on comprehensive analysis of flow and pollutant concentration data, the accuracy of the test result is improved. According to the method, the emission quality and the specific emission amount in unit time can be accurately calculated, clear quantitative indexes are provided for whether the vehicle reaches the standard or not, the functions are used in cooperation, the high efficiency, the accuracy and the traceability of tail gas detection are guaranteed, and the method has remarkable practical value for improving environment monitoring and pollutant control.

The application provides a PEMS testing method and system for a sweeper engine, the method comprising: obtaining an engine model corresponding to a target sweeper, and building an engine test bench according to the engine model, and installing and debugging a PEMS device on the engine test bench; obtaining all operation modes related to the target sweeper, and testing the engine test bench according to a test condition corresponding to each operation mode; monitoring rotational speed data and emission data of the engine test bench in each test process, and evaluating a PEMS emission result of the sweeper according to the rotational speed data and the emission data. The PEMS testing method for the sweeper engine can greatly shorten a non-road emission test time of the sweeper by simulating actual road operation conditions of the sweeper.

The embodiment of the application discloses a kind of diagnostic process abnormality monitoring method, device, medium, OBD module and vehicle;Based on abnormality monitoring method, the leakage failure that can occur in fault diagnosis process is included in the main object of monitoring, by the signal monitoring of the object to be monitored, especially the signal monitoring of the evaporation system of fuel vehicle, on the basis of analyzing signal characteristics, with existing hardware structure, the abnormality monitoring of fault diagnosis system is realized;In addition, the related scheme is also applicable to the development of computer storage medium, OBD module and intelligent vehicle, and the upgrading of original system can be conveniently realized by the upgrading of control software.

Provided is a drive sound determination device capable of determining whether or not the drive sound of a diesel engine is caused by resonance sound. A drive sound determination device is provided with: a measurement unit that measures the drive sound of a diesel engine; a first calculation unit that calculates a driving sound frequency, which is the frequency of the driving sound; a second calculation unit that calculates a resonance frequency, which is the frequency of a resonance sound caused by combustion pressure in a cylinder of the diesel engine, on the basis of information relating to the type of the diesel engine and information relating to the operating state of the diesel engine; and a determination unit that determines whether or not the driving sound is caused by the resonance sound on the basis of the driving sound frequency and the resonance frequency.

A method for attenuating interference in the measurement of an angle of sideways tilt of a motorized two-wheeled vehicle including an electronic control unit configured to compute an angle of sideways tilt of the vehicle from the measurements of a tilt sensor. The method includes: reception of the value of the speed of the vehicle measured by the speed-measuring module; reception of the number of revolutions per minute of the engine; computation of the ratio between the received speed value and the received number of revolutions per minute; comparison of the ratio between the received speed value and the number of revolutions per minute with an attenuation interval; if the ratio is outside the attenuation interval, computation of the tilt angle without attenuation; if the ratio is within the attenuation interval, computation of the tilt angle with attenuation.

The application discloses a knock detection method, a knock detection device, computer equipment and a computer storage medium, wherein the knock detection method comprises the following steps: acquiring a pressure signal in an engine combustion chamber; acquiring a resonance frequency of engine knock; decomposing the pressure signal into a high-frequency component signal and a low-frequency component signal according to an empirical mode decomposition method; obtaining a center frequency of the high-frequency component signal according to the high-frequency component signal; in response to the center frequency being located in a range of the resonance frequency, calculating a knock factor according to the low-frequency component signal and the high-frequency component signal; comparing the knock factor with a knock threshold value of the engine, and in response to the knock factor being greater than or equal to the knock threshold value, judging that the engine knocks; and in response to the center frequency being located outside the range of the resonance frequency, or in response to the knock factor being less than the knock threshold value, judging that the engine does not knock. The knock detection method can detect whether the engine knocks.

This application provides a method for determining the flywheel dynamics of an engine's half-order vibration. Three displacement sensors are arranged on the flywheel housing facing the flywheel, and the displacement signal of each sensor is collected. The displacement signal represents the change in the vertical distance between each sensor and the flywheel. Based on the displacement signal and the coordinate values ​​of the displacement sensors, a disturbance signal of the flywheel is calculated. The frequency and time of the half-order vibration are determined. Based on the disturbance signal and the frequency and time of the half-order vibration, the flywheel dynamics when the engine experiences half-order vibration are determined. According to the method provided in this application, by collecting displacement signals of the vertical distance between at least three displacement sensors and the flywheel, a disturbance signal on the flywheel plane is calculated; then, by obtaining the frequency and time of the half-order vibration, the flywheel dynamics when the half-order vibration occurs are determined.

The application belongs to the technical field of engine detection devices, and specifically discloses an engine piston running state detection device, which comprises a conveying belt mechanism, a visual detection mechanism and a vibration detection mechanism; support vertical poles are installed on the front and back sides of the conveying belt mechanism; the two support vertical poles are the same in structure and are arranged in a staggered mode; the visual detection mechanism and the vibration detection mechanism are respectively installed on the two support vertical poles; the visual detection mechanism is located on the left side of the vibration detection mechanism; the visual detection mechanism comprises a mounting frame, a sliding machine box, a machine box driving motor and a visual sensor; the detection device has good universality, can meet the detection work of engines of different specifications, and is very flexible; the expandability of the hydraulic clamp in the vibration detection mechanism can adapt to engines of different sizes; the flexible movement of the multiple vibration detection heads on the track rod can detect pistons at different positions, and the comprehensiveness and accuracy of the detection are improved.

A misfire diagnosis device that diagnoses presence or absence of a misfire in an engine having a plurality of cylinders, includes: a setting unit configured to set a calculation interval to a period during which at least all cylinders make one cycle of ignition; a recording unit configured to record a crank angular acceleration from one cylinder ignition to next cylinder ignition for each cylinder; a calculation unit configured to calculate a difference between a maximum value and a minimum value of the crank angular acceleration in the calculation interval for each cylinder; and a diagnosis unit configured to diagnose, for each cylinder, a cylinder for which the difference in the crank angular acceleration is equal to or greater than a threshold value as a misfiring cylinder.

The application discloses a multi-station diesel engine test running system, which is applied to the technical field of diesel engine test running and comprises a test running production line and a test running system. The test running production line comprises a conveying belt, a first station, a plurality of second stations, a controller, a first detection mechanism, a second detection mechanism and a diesel engine. The test running system is arranged in the controller. The first detection mechanism comprises a dynamometer, a plurality of vibration sensors, a plurality of noise sensors and a plurality of cylinder three. The dynamometer drives the diesel engine to idle without combustion in the cold running-in stage. The vibration sensors are used for acquiring vibration amplitudes at different positions of the diesel engine during test running. The noise sensors are used for acquiring sound decibel values at different positions of the diesel engine during test running. The test running system comprises an acquisition module, an analysis module and a warning module. The acquisition module is electrically connected with the first detection mechanism and the second detection mechanism. The application can improve the test running efficiency of the diesel engine.

The invention discloses an excavator emission degradation test method and device, a terminal and a storage medium, and the method comprises the steps: sending an operation instruction, and enabling an excavator bucket to execute unmanned no-load excavation operation; corresponding first remote monitoring information, second remote monitoring information and third remote monitoring information under different working durations of the excavator are obtained, the first remote monitoring information comprises test information which is output by the PEMS and represents the discharge level of the excavator, and the second remote monitoring information comprises excavator power system monitoring information; the third remote monitoring information comprises monitoring information of the SCR post-processing system of the excavator; and according to the first remote monitoring information, the second remote monitoring information and the third remote monitoring information, establishing a fitting relationship between the excavator emission level and the excavator power system monitoring information and the excavator SCR post-processing system monitoring information, thereby obtaining an excavator emission degradation test result. According to the invention, the accuracy of the emission degradation test result can be greatly improved.

The invention relates to a method for controlling a hybrid powertrain of a vehicle and a hybrid powertrain with a drive unit comprising an internal combustion engine with a crankshaft and a first electric machine with a first rotor shaft, wherein the crankshaft and first rotor shaft are connected to each other by means of a rotary connection, a second electric machine with a second rotor shaft, wherein rotational characteristics of the rotor shafts and the crankshaft are detected by means of sensors and the rotor shafts can be connected to each other by means of a clutch switched by a hydraulic actuator depending on the rotational characteristics.In order to maintain the operational readiness of the hybrid powertrain even in the event of a sensor failure and to avoid vehicle breakdowns in this regard, substituted rotational parameters are generated based on rotational parameters of the crankshaft or the first rotor shaft, taking into account a translation of the rotary connection, in the event of a sensor failure of the first rotor shaft or the crankshaft.

A diagnostic system for an engine system comprising a plurality of engine cylinders (30) and an air intake manifold (44) for receiving an intake of air during an intake phase of an engine cycle, the diagnostic system comprising; a plurality of fuel injectors (46), each for delivering fuel to an associated one of the engine cylinders (30) via the air intake manifold (44), wherein each of the plurality of fuel injectors (46) has an injector-open state when the fuel injector (46) is delivering fuel during the air intake phase of the associated engine cylinder (30) and an injector-closed state when the fuel injector (46) is not delivering fuel; and a sensor configured to measure the air pressure in the air intake manifold. The diagnostic system further comprises a controller (18) configured to determine an occurrence of a backfire event in the air intake manifold (44) on the basis of the measured air pressure; measure the number of backfire events in the air intake manifold which are associated with one of the fuel injectors (46); compare the number of backfire events with a predetermined count threshold, and, if the measured number of backfire events is greater than the predetermined count threshold, output a warning signal.

The present disclosure provides a method and system for diagnosing wear of a fuel system of a diesel engine. The method comprises: acquiring injection parameter data of the fuel system in an injection combustion process, and pressure signal data in an oil pipe; collecting particulate matters in exhaust gas in the injection combustion process by using an electrostatic deposition sampler, and shooting images of the particulate matters by using a microscopic camera device to extract morphology data of the particulate matters from the images; emitting pulsed laser to the particulate matters by using a laser-induced breakdown spectrometer to excite plasma emission characteristic spectrum in the particulate matters to obtain composition data of the particulate matters according to the characteristic spectrum; extracting features of the injection parameter data, the morphology data of the particulate matters and the composition data of the particulate matters respectively to obtain injection features, morphology features of the particulate matters and composition features; performing time-frequency analysis on the pressure signal data to obtain pressure features; and inputting the injection features, the pressure features, the morphology features and the composition features into a wear diagnosis model to obtain a wear diagnosis result.

The application discloses a methanol injection method of a methanol engine, relates to the methanol engine, and transmits methanol fuel sprayed from a methanol nozzle in a spiral transmission mode to separate atomized methanol fuel from methanol droplets, wherein the atomized methanol fuel is transported into a combustion chamber, and the methanol droplets are transported to a methanol nozzle injection side to be heated and evaporated. The application further discloses a methanol injection device and a calibration method of the methanol engine. The application fully utilizes the energy of air to evaporate the methanol droplets, guarantees the evaporation effect of methanol particles, and improves the atomization efficiency of the suspended droplet particles.

The invention discloses a fuel supply device and a mixed fuel engine test bench, the fuel supply device comprises a raw material supply module, a fuel mixing module, a first conveying pipeline, a second conveying pipeline and a third conveying pipeline, the raw material supply module comprises a first fuel module and a second fuel module; the fuel mixing module comprises a mixed fuel storage tank and a weighing device, the weighing device is used for obtaining the mass change of the mixed fuel storage tank, the first conveying pipeline is connected between the first fuel module and the mixed fuel storage tank, and the second conveying pipeline is connected between the second fuel module and the mixed fuel storage tank. According to the invention, the weighing device is used for weighing the mixed fuel storage tank, so that the mixed fuel with an accurate proportion can be obtained in a test room, the waiting time cost in the test process is reduced, and the test efficiency is improved. The problem that the transportation cost and the transportation risk of the mixed fuel needed by the test are high is solved.