AVL PLU131 Flow Measurement Systems - Fuel mass flow

AVL PLU131 Flow Measurement Systems

AVL PLU131 Flow Measurement Systems are high-precision flow meters and flow measurement systems for injector, pump or control valve characterization in production, R&D and engine application.

AVL Approach

AVL provides a large spectrum of flow sensors and system solutions for these tasks with either continuous flow rate metering or injection quantity measurement.

R&D
R&D applications focus on component characterization and validation under a wide range of operation conditions.
Injection quantity measurement and injection rate analysis on component and system test benches. The most prominent group of test objects is fuel injectors (CR, GDI, Port Fuel Injectors, Unit Injectors, SCR Injectors etc.; solenoid and piezo) and fuel injection systems.

Injector testing includes injection quantity characterization versus parameters as energizing time, pressure or temperature (Q(ti,p,T). But it also comprises analysis of needle movement and timing (open and closing) as well as injection rate shaping etc.

Injection system testing investigates multiple injector interaction in a complete engine injection system. Pressure wave compensation, for instance, investigates mutual influence on flow characteristics depending on pressure and engine speed.

Production
Component manufacturing requires quality control, adjustment or calibration of mass products like injectors, pumps, control valves etc. Sample checking or 100% control of flow characteristics is mostly realized via continuous flow measurement where short measurement time and high reliability are the most important features.

Benefits at a Glance

Test time reduction: higher accuracy reduces averaging time
Process acceleration in R&D : reliable characterization and fast verification of progress
Cost reduction in application: engine map pre-calibration reduces engine test bed time
High reliability: robust sensors and extreme long-term stability of the calibration due to PLU measurement principle

Market Requirements

Production testing for diesel and gasoline fuel injectors includes a variety of integrated measurement solutions ranging from random inspection on semi-automated test benches to 100% control on fully automated production lines. Similar manufacturing test requirements apply to fuel pumps and control valves. R&D and engine applications add further tasks as flow characteristic verification, injector timing map calibration or combustion development.

Technical Data

AVL PLU 131 Flow Sensor Specifications

	STS PLU 131 Fuel	STS PLU 131 Urea	PLU 131F	PLU 131S
Sensor type	Injection rate and quantity measurement sensor including high-speed data acquisition system		Average flow rate
Typical applications	High pressure direct fuel injection component and system testing in R&D, production, engine application, racing, etc.	SCR injector and dosing system testing in R&D and production	Low pressure fuel injector and fuel pump production testing; high-precision fuel flow- measurement in R&D	High temperature or high pressure fuel injector and fuel pump production testing
Standard configuration	Downstream or Upstream		Upstream
Measurement parameters	Flow rate, injection rate and quantity with up to 12 partial injections, injector current, injector opening and closing delays, pressure, temperature		Momentary flow rate, total consumption and statistical data in combination with data acquisition system
Measurement range
Flow rate	0.01 ... 10 l/h	0.01 ... 10 l/h	0.05 ... 10 l/h	0.05 -10 l/h
	0.02 ... 20 l/h	0.02 ... 20 l/h	0.05 ... 20 l/h	0.05 - 20 l/h
	0.04 ... 40 l/h	0.04 ... 40 l/h	0.1 ... 40 l/h	0.1 - 40 l/h
			0.15 ... 75 l/h	0.2 - 80 l/h
			0.3 ... 150 l/h	0.3 - 150 l/h
			0.8 ... 300 l/h	0.8 - 300 l/h
Injection quantity	0.1 ... 600 mm³	0.1 ... 600 mm³
Measurement uncertainty
Flow rate*)	0.1 %	0.1 %	0.1 %	0.1 %
Total measure- ment uncertainty**)	1 % at > 2 mm³ shot volume	1 % at > 10 mm³ shot volume and 4 Hz cycle rate
Cycle rate	10 ... 180 Hz	1 ... 10 Hz
Dynamic response time acc. DIN 19226			<100 ms	<100 ms
Media	Common gasoline and Diesel fuels and compatible test media; alcoholic additives up to 100 %	Aqueous urea solution according to ISO22241 2008/9 (AdBlue®) *), De-ionized water with 1 % Prevox or 50% ethylene glycol **)	Common gasoline and Diesel fuels and compatible test media; alcoholic additives up to 100 %	Common gasoline and Diesel fuels and compatible test media; alcoholic additives up to 100 %
Density	0.69 ... 0.85 g/cm³	0.99 ... 1.19 g/cm³	0.69 ... 0.85 g/cm³	0.69 ... 0.85 g/cm³
	Further media densities upon request
Operating temperature
Media	-30 - +70 °C	+10 - +60 °C	-20 - +70 °C	-30 - +70 °C
Environment	-30 - +60 °C	+10 - +60 °C	-20 - +60 °C	-30 - +60 °C
	Up to 150 °C with optional cooling flange			Up to 150 °C with optional cooling flange
Operating pressure	0.01 - 200 bar	0.01 - 10 bar	0.1 - 10 bar	0.01 - 200 bar
Differential pressure	ΔP=0 (PLU measurement principle)
Back pressure	No minimum back pressure required
Interfaces	Frequency (max. 150 kHz)	Frequency (max. 150 kHz)	Frequency (max. 70 kHz)	Frequency (max.150 kHz)
Power supply	100 - 240 V AC 50/60 Hz (STS Control Unit)	100 - 240 V AC 50/60 Hz (STS Control Unit)	24 V - 40 V DC	24 V - 40 V DC
Power consumption	Max. 50 W	Max. 50 W	Max. 40 Watt	Max. 40 Watt
Sensor dimensions (W x H x D)	335 x 216 x 140mm (W x D x H ) 363 x 216 x 140mm (W x D x H ) including cooling flange	335 x 216 x 140mm (W x D x H )	340 x 216 x 133 mm	335 x 216 x 140mm (W x D x H ) 363 x 216 x 140mm (W x D x H ) including cooling flange
Sensor weight	16 kg	15 kg	10 kg	14 kg
Protection			Ex II 2G EEx d IIB T6	Ex II 2 G EEx d IIB T6 acc. EN 50 018:1994, EN 50 014:1997
Safety	CE	CE	CE	CE
Calibration	Traceable back to German national standard (PTB)

*) Measurement uncertainty of flow meter calibration factors under repeatable conditions with medium HAKU at 20 °C and 1 bar
**) Total measuring uncertainty acc. GUM ( Guide to the Expression of Uncertainty in Measurement ) for an optimized injection system
***) AdBlue® is a trademark of the VDA for the official name Urea AUS 32 according to ISO 22241 2008/9
****) De-ionized water solution with 1% P3-Prevox 7400 (99/1 vol%) or with 50% ethylene glycol (50/50 vol%)

System Scope

Continuous Fuel Flow Measurement
Fuel pumps, control valves and diesel and gasoline low pressure injectors are typically tested in operation as a final step in the production process. Average fuel flow quantity examination over a characteristic flow range is used as performance check for the devices.

For this purpose AVL offers the PLU131 flow sensor family with the following features:

High-accuracy continuous fuel flow meters for a wide temperature and pressure range
Large measuring range up to 1:500 at high resolution provide for short measurement time
Extreme sensor robustness and long-term stability of calibration

Fuel Injection Quantity Measurement
High pressure systems for direct fuel injection like common rail diesel or GDI require cycle-resolved shot quantity measurement for performance examination as well as for production quality check, featuring:

Shortest measurement time for flow characteristic verification in end-of-line testing

R&D applications include further tasks in injector and system characterization, such as:

Crank-angle resolved injection rate analysis for combustion development
Precise shot measurement of multiple injections for injection system pressure wave compensation and injection timing map calibration

With the Shot-to-Shot™, PLU131 AVL provides a state-of-the-art shot measurement system compliant with the most extreme requirements of OEMs and component suppliers.

Aqueous media (AdBlue®) and extremely low flow rate
Low pressure injection systems are used for diesel engine exhaust aftertreatment in SCR systems for NOx reduction and HC dosers for DPF regeneration. Extremely low flow rates and small dosing quantities are particular challenges for characterization and performance testing of these dosing systems. AVL offers system solutions that are well adapted to these special requirements.

System Integration Service
AVL provides integration support to system integrators as well as end users for the full range of flow sensors and system solutions and for a variety of measurement tasks.

Measuring Principle

PLU Measurement Principle
AVL PLU sensors combine the most suitable measurement technology for these specific applications with high reliability and extreme long-term stability of the calibration.

The PLU measurement principle offers a number of advantages:

Extremely large measuring range of up to 1:1000
High accuracy even at very low flow rates <10g/h
No pressure drop (Δp=0) and consequently no influence on the dosing system
No leakage over the gear counter due to (Δp=0)

The PLU measurement principle, with two independent positive displacement sensors, combines the highly dynamic sensitivity of a piston sensor with the extremely robust accuracy of a servo-controlled gear meter. It prevents any interference of the flow meter with the hydraulic system to be measured. The sensor cancels out the pressure difference (ΔP=0) between inlet and outlet, avoiding leakage alongside the gears.