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Guideline for the Preparation of ICEE 2003 Paper e ISSN 2582 5208 International Research Journal of Modernization in Engineering Technology and Science Volume 03/Issue 05/May 2021 Impact Factor 5 354[.]
e-ISSN: 2582-5208 International Research Journal of Modernization in Engineering Technology and Science Volume:03/Issue:05/May-2021 Impact Factor- 5.354 www.irjmets.com STUDY OF INTERNAL INJECTION SYSTEM ON SMALL CAPACITY DIRECT INJECTION DIESEL ENGINE Song - Ngo Duy*1, Minh – Tran Anh*2, Thanh – Pham Van*3, Thoi – Le Nam*4 *1,2,3,4Dong Nai Technology University, Dong Nai, Vietnam ABSTRACT This paper shows a study on the monitoring and measuring system for fuel injection pressure in a small diesel engine with direct injection type Injection pressure has a closed relation to injection rate and directly affected to injection characteristics and so engine performance characteristics In this work, a study on designing, manufacturing and preliminary results of measuring system for injection pressure are shown to estimate the effects of injection pressure on the engine performance characteristics The system included two steps: (1) utilization of an analog card to record the magnetic signal from the sensor installed in the high-pressure pipe and (2) connection of PIC16F877A and PC based LabVIEW software to monitor the change of injection pressure The obtained results will be used for the investigation of the effects of injection pressure change on engine performance characteristics in the next steps Keywords: Pressure Sensor, PIC16F877A, Measuring Systemfor Injection System, Diesel DI Engine I INTRODUSION To evaluate and study the influence of fuel injection pressure on the power and emission characteristics of a single-cylinder, direct-injected diesel engine with small capacity, the fuel injection pressures are varied in a wide range To detect the instantaneous change in injection pressure over time during engine operation, a system to monitor the pressure variation on the high-pressure hose is designed and manufactured The injection pressure monitoring system consists of separate parts: (1) pressure sensor (2) communication and signal conversion card (3) background control software Computer communication has many applications in science and technology including measurement, monitoring, automatic control… RS232 is a convenient serial communication interface standard that allows easy data sending and receiving With the RS232 interface, the authors establish a connection between the microcontroller and the computer to read the value of the electrical signal (analog signal) from the pressure sensor to display the instantaneous fuel injection characteristic curve for the diesel engine Sprayed directly over time, the oil pressure sensor has the characteristics shown in Table Table 1- Parameter table of Sensys, Nozzles Pressure range ~ 250 bar Way out 1-5V Operating temperature 40~125℃ Vibration resistant 20G, 20~200Hz Solvent Water, oil, gas Origin Korea II METHOD AND EQUIPMENT USED In the test step, the monitoring system is performed on the Vikyno 12.5 HP engine and on the power engine test bench The output of the high-pressure pump and the high-pressure oil pipe is improved to include a pressure sensor to take the signal of pressure variation as shown in Figure 2.1 www.irjmets.com @International Research Journal of Modernization in Engineering, Technology and Science [3326] e-ISSN: 2582-5208 International Research Journal of Modernization in Engineering Technology and Science Volume:03/Issue:05/May-2021 Impact Factor- 5.354 www.irjmets.com Figure 2.1 - Location of fuel pressure sensor in direct injection 1-cylinder diesel engine Hardware design includes: Sensor input and power block, RS232 communication standard, ADC converter block, PIC16F877A microcontroller block The power block is designed separately to prevent interference between the sensor source and the PIC16F877A microcontroller source Figure 2.2 - Power block and sensor input Standard RS232 communication block Standard RS232 is connected to a jack (called COM port) When in use, you can use or all of the pins (pins) of this port Only transmitting and receiving signals should only use signal wires (pin Transmit Data TxD), receive signal (pin Receive Data RxD) and a ground wire (GND - ground, or ground) Figure 2.3 - RS232 Communication standard The ADC converter block uses a 12-bit microchip MCP3202 Convert Analog signal from 1- 5V fuel injection pressure sensor into Digital signal 819-4095 and communicate with PIC16F877A microcontroller via SPI protocol Figure 2.4 - ADC Converter block Control Pic 16F877A www.irjmets.com @International Research Journal of Modernization in Engineering, Technology and Science [3327] e-ISSN: 2582-5208 International Research Journal of Modernization in Engineering Technology and Science Volume:03/Issue:05/May-2021 Impact Factor- 5.354 www.irjmets.com Figure 2.5 - PIC16F877A Microprocessor block III DESIGN OF SIGNAL ACQUISITION SOFTWARE Set up algorithm flow chart to read and display pressure signal as shown in Figure 2.6 Algorithm and algorithm diagram on LabVIEW software and presented in Figure 2.7 and Figure 2.8 Figure 2.6 - Algorithm flowchart setup The received data will be transmitted via the RS232 serial port which is done asynchronously Therefore, only one bit can be transmitted at a time (1 character) The transmitter sends a start bit to notify the receiver of a character to be sent in the next bit transmission This bit always starts with 0… Followed by data bits (bits) sent as ASCII code (wit can be 5,6,7 or data bits) Then a Parity bit (Checks for even, odd or not) and finally a stop bit - the stop bit can be 1, 1.5 or stop bits Figure 2.7 - RS232 Port communication parameters www.irjmets.com @International Research Journal of Modernization in Engineering, Technology and Science [3328] e-ISSN: 2582-5208 International Research Journal of Modernization in Engineering Technology and Science Volume:03/Issue:05/May-2021 Impact Factor- 5.354 www.irjmets.com IV RESULT ANS DISCUSSION Some results of design, manufacture and testing of injection pressure measurement system have been obtained and presented from Figure 3.1 to Figure 3.6 Figure 2.8 - Algorithm displayed on LABVIEW The complete hardware (signal conversion circuit) is shown in Figure 3.1 Which includes: power supply, signal connection port from pressure sensor, microcontroller PIC16F877A, converted signal port to PC via RS232 connection Figure 3.1 - Complete hardware Figure 3.2- Dashboard in LabVIEW When the necessary software and hardware are available, connect to the PC through the interface with LabVIEW (Figure 3.2) Select the COM port according to the path shown in Figure 3.3 Make a direct connection Run a check of the motor before conducting the test Run the LabVIEW interface program and directly export the fuel injection characteristic curve over time in Figure 3.4 www.irjmets.com @International Research Journal of Modernization in Engineering, Technology and Science [3329] e-ISSN: 2582-5208 International Research Journal of Modernization in Engineering Technology and Science Volume:03/Issue:05/May-2021 Impact Factor- 5.354 www.irjmets.com Figure 3.3: Checking the COM with connection port Figure 3.4- Variation of fuel injection pressure over time at 1200 rpm Figure 3.5- Variation of fuel injection pressure signal over time at 2400 rpm Experimental results (Figure 3.4 and Figure 3.5) at various engine speeds show the stability of the measured and displayed values of the change in injection pressure with time (crankshaft rotation) (b) Result measured by oscilloscope FLKUE (a) Results from the system Figure 3.6 The results of the oscilloscope from FLUKE Comparison of measurement results of research system (a) and FLUKE oscilloscope (b) The results obtained from the signal receiving circuit are compared with the measurement results of the oscilloscope from FLUKE (USA) and are presented in Figure 3.6 The comparison on Figure shows the consistency of experimental results because of the two devices Therefore, the results obtained from the measurement system have high reliability V CONCLUSION The fuel injection pressure variation monitoring system is designed, manufactured and tested on the engine power test bench Preliminary results show the stability of the measurement results at different speed ranges and the reliability of the measurement results and comparison with the calibrated instrument This is the basis www.irjmets.com @International Research Journal of Modernization in Engineering, Technology and Science [3330] e-ISSN: 2582-5208 International Research Journal of Modernization in Engineering Technology and Science Volume:03/Issue:05/May-2021 Impact Factor- 5.354 www.irjmets.com for the application of equipment in the process of monitoring the change of fuel injection pressure during operation and evaluating engine technical features VI REFERENCES [1] Cory L Clark, LabVIEW Digital Signal Processing and Digital Communications Copyright © 2005 by the McGraw-Hill Companies, Inc [2] Nguyen Ba Hai, "LabVIEW Programming", National University Publishing House, Ho Chi Minh City, 2012 [3] Pic16f87a data sheet Microchip Technology Inc., DS39582B-page 2, 2003 [4] Mcp3202 Data Sheet, Microchip Technology Inc., Ds21034d-page 1, 2006 [5] Nguyen Tat Tien, "Principles of internal combustion engines", Education Publishing House, 2000 www.irjmets.com @International Research Journal of Modernization in Engineering, Technology and Science [3331] ... Figure 3.3: Checking the COM with connection port Figure 3.4- Variation of fuel injection pressure over time at 1200 rpm Figure 3.5- Variation of fuel injection pressure signal over time at 2400... obtained from the measurement system have high reliability V CONCLUSION The fuel injection pressure variation monitoring system is designed, manufactured and tested on the engine power test bench Preliminary... 5.354 www.irjmets.com for the application of equipment in the process of monitoring the change of fuel injection pressure during operation and evaluating engine technical features VI REFERENCES