ONO SOKKI -Time-series data analysis software OS-2000 series

Application

Background

In current automobile measurement, partial optimization for each measurement factor is often performed. But from now on, it is becoming an important keyword to perform total optimization of whole vehicle body. Reflecting this keyword, correlation analysis is performed between engine torque calculated from combustion pressure in combustion analysis system and wheel torque measured by wheel torque meter. Figuring out the correlation between engine torque and wheel torque by using this system greatly help improvement of fuel efficiency or reduction of CO² emissions.

System Configuration

	Model name	Product name	Remarks
1	OS-2710 pack for bench	Time series data analysis software	Made by Ono Sokki
2	DS-2184B	Combustion Analyzer	Made by Ono Sokki
3	-	Spark plug with cylinder pressure sensor	Made by Kistler
4	-	Charge amplifier	Made by Kistler
5	DS-3104	Data station	Made by Ono Sokki
6	-	Wheel torque meter	Made by Kistler

Test procedure

1. The measurement test on a chassis

Measurement test is performed on a chassis with both acceleration-deceleration and constant running patterns.
In this test, the correlation of power is analyzed between engine torque calculated from combustion pressure in Combustion Analyzer and wheel torque measured by wheel torque meter.

Figure1. Measurement on a chassis

Running pattern
(1) Acceleration-deceleration test

Accelerate up to 90 km/h in five periods in order (30s/25s/20s/15s/10s, five trapezoid patterns)
at B-range*.

(2) Constant test

Two continuations of 40km/h→60km/h→80km/h→60km/h→40km/h
(Performed at D-range* in the first half, B-range* in the late)

*B-range: shift position of [Brake] D-range: Shift position of [Drive]

2. In-vehicle measurement test

Measurement test is performed using an actual vehicle equipped with measurement instruments. As same as the measurement test on a chassis, the correlation of power is analyzed between engine torque calculated from combustion pressure in Combustion Analyzer and wheel torque measured by wheel torque meter.

Running pattern
(1) Accelerated at full throttle

3. Analysis method

Calculate engine torque from each combustion pressure of four-cylinder using the DS-2184B Combustion Analyzer.
Convert the engine torque into text file of time-based data at every 0.1 ms.
Record three data of wheel torque, engine rotational speed and wheel rotational speed to the DS-3104 Data station.
Import the above four data (underlined items) to the OS-2710 to compare the power of engine and wheel. The power is calculated applying equation1, and analyzed with the 2-data analysis function of the OS-2710.

Power [kW]=Torque [Nm]×Rotational speed [r/min]×2n/60/1000 ···Equation 1

Test results