Exploitable results
The main objective of Econox II project was to develop a gas sensor prototype for automotive applications, as close as possible to an industrial device. This objective has been reached concerning the sensing element part (substrate + heating element + sensing layer + electrodes + protective film). Effectively, at the end of the project, the prototypes were entirely produced by screen-printing technology in industrial conditions by Microtel. Their reproducibility is quite well controlled and their stability has been widely improved compared to initial prototypes.
Finally, the key point is the potentiality of the sensor to be used for automotive applications.
Tests performed by CR Fiat, Renault and Volvo lead to the following conclusions:
- Econox sensor is widely sensitive to CO and HC (hydrocarbons) and is able to diagnose the oxidation catalyst.
- The use of Econox sensor for NOx trap application is possible but difficult due to the detection of NO2 only (not NO).
- A potential application for HD Diesel engine with SCR system (Selective Catalytic Reduction) using urea is NH3 detection.
- The preliminary durability tests show a sufficient stability of the sensor performances.
The main results of ECONOX II project can be summarised in three parts:
1) The knowledge and experience to develop simple and low cost gas sensors for detection in harsh conditions.
The first point concerns mainly Armines, Politechnico and Microtel, respectively with regard to sensor principle, material for sensors and sensor manufacture by screen-printing technology.
The innovative points and benefits are:
- The simple principle, which is used for the detection: measurement of the electrical potential created by the difference of the kinetics of reactions of gases on two different electrodes.
- Robust technology: thick film technology on ceramic substrates and sintering process with the low cost production by a SME and the stability of materials.
- The possibility of selective detection using the temperature of the sensors: low temperature (400°C) for NOx, medium temperature (500°C) for HC and high temperature for CO (600°C).
The potential market is the instrumentation market, which needs gas sensors with specific performances to develop gas detection applications with medium prices (not ultra-low cost as the consumer market). The advantages for environmental controls are related to the possibility to develop network of sensors for pollution control. However, the performances are very dependent on the working conditions. Consequently, it will be necessary to have R&D actions (6 months to 2 years) between some of the partners of Econox's consortium and end-users in order to define the optimum conditions to use the sensors according to the type of application.
2) The development of particular device (ECONOX II prototypes) for the control of CO / HC / NOx in car exhausts.
The second part, concerning Econox II prototype, one of its main advantages is the simple planar structure, which allows one to obtain uncomplicated and unsophisticated devices. Moreover, as the specific performances depend on the accurate control of the sensor temperature, special casings and ECU (Electronic Control Unit) have been designed to have a good thermal regulation of the sensing element. The resulting advantage is the possibility to use the sensors directly in car exhausts. Except the oxygen sensors or the new NOx Japanese sensors, only few sensors are able to work in exhausts. The potential end-users are the car manufacturers for various exhausts controls: OBD, DeNOx or NOxTrap, or motor control. For such applications, the producers will be car suppliers. The market size depends on the future legislation and on the price of the devices. In regards of the few sensors available on the market, the advantages of the present device are its relatively low price linked to its simple principle.
However, selectivity may be insufficient for some applications. The sensing device can be improved by new R&D actions on the sensing material. The actual prototypes thus constituted a basis for further research on sensor improvement (research partners) and for investigation of exploitation strategies for car application (industrial partners).
3) The exploitation strategies concerning the use of the sensor for car applications: pollution equipment control.
The last point deals with car applications. According to the results of experiments on motor benches achieved by the car manufacturers, some special conditions of use have been demonstrated. The same sensor could provide different information according to the working conditions; position of sensor, flows, temperature, casing. For example, the selectivity versus gases is very dependent on these conditions. Hence, the main interest is related to the possibility to use a similar sensing device, including sensor, casing and the Electronic Control Unit, for several applications. The device is able to control CO or HC or NOx for special exhaust applications. Consequently, the size of the market could be large. The suppliers, who will decide to produce the sensing devices, must be able to offer a generic solution to different applications in the car industry. This is a high advantage for the car industry, which needs low cost devices. However, the counterpart is that a generic device often requires a specific R&D action for target applications.
Buscando datos de OpenAIRE...
Se ha producido un error en la búsqueda de datos de OpenAIRE
No hay resultados disponibles