Umicore is one of the world's leading producers of catalysts used in automotive emission systems. The company develops and manufactures high performing catalysts for, among other things, gasoline and diesel engines to transform pollutants into harmless gases, resulting in cleaner air.
Umicore's production location in Suzhou "Umicore Technical Materials" is using Bronkhorst Mass Flow Controllers and Vapor Systems for research and testing of automotive emission catalyst materials. Newly developed catalytically active materials of Umicore consist of oxides and precious metals, such as platinum and palladium, incorporated into a porous structure which allows intimate contact with the exhaust gas.
What Catalyst materials does Umicore Test?
Umicore in Suzhou uses various test benches in which newly developed catalytic materials are tested on performance (read: low output of toxic emissions). "Umicore develops new catalysts directly with top-tier automobile manufacturers in China. We are testing new formulations of materials and shapes of the catalysts on performance" explains Mr. Yang Jinliang
How are the mass flow meters and controllers applied for identical testing and simulation
The Bronkhorst mass flow meters and controllers are used to accurately deliver the right amount of several gases in a mixture that simulates the exhaust of an engine in different circumstances. "To really compare the performance of newly developed formulations, we have to be sure that the operational conditions of our tests are identical." Mr. Yang explains that this requires the use of high performance mass flow controllers to accurately mix the simulated exhaust gas.
"We need flow control equipment which is reliable and has excellent repeatability during our simulation runs. Therefore Umicore developed the test equipment together with the Bronkhorst flow specialists." Umicore runs various simulations. "We simulate exhaust gases of engines under various life cycle simulations and operating conditions. For example, the exhaust gas of the car is different if the engine is still cold or if the engine has a high number of revolutions."
Test Bench for aging simulation
One special test bench of Umicore simulates the aging of the catalyst materials. This has been achieved by heating the ambient temperature of the Catalyst up to 800° celsius for a couple of hours up to 24 hours in a test run while adding the simulated exhaust gas. "Here the bronkhorst instruments prove high stability under the harsh testing conditions" says Mr. Yang.
Exhaust gas simulation recipe
In order to stimulate engine exhaust gas, Umicore mixes multiple gases. In general the following reactions take place in the catalytic converter:
- Reduction of nitrogen oxides to nitrogen and oxygen: 2NOx → xO2 + N2
- Oxidation of carbon monoxide to carbon dioxide: 2CO + O2 → 2CO2
- Oxidation of unburnt hydrocarbons (HC) to carbon dioxide and water: CxH2x+2 + [(3x+1)/2]O2 → xCO2 + (x+1)H2O
To mix these gases, EL-FLOW Select digital mass flow controllers are being used. In order to maintain the gas mixture under the same pressure, an EL-PRESS pressure controller instrument is used to control the pressure simultaneously with the flow.
Exhaust gases of engines also contain evaporated H20. For this purpose the Bronkhorst Controlled Evaporation Mixer (CEM) is used. All digital mass flow controllers, pressure controller and the CEM are connected with a computer that runs a software program to control the instruments.
In the aging simulation test-bench of Umicore, high-temperature mass flow controllers of Bronkhorst are applied. The Bronkhorst
EL-FLOW Select flow controllers have remote electronics to resist gas temperatures as high as 110° Celsius and still control the gases with high accuracy and excellent repeatability.
How do you like the support of Bronkhorst products in China?
When asked about Bronkhorst support and service in China, Mr. Yang is very enthusiastic:
“All Bronkhorst experts in China are very professional and have quick response. Especially during the start-up phase of our project, when we needed it most, my contacts were determined to support us. The system runs smoothly, but it’s comfortable to know that Bronkhorst is having one of its Global Service Offices in Shanghai if we need calibration or service.”
Simulation of exhaust gas to test lambda probe
Each modern car with a combustion engine has a self-controlling way to optimize the engine performance. A lambda probe, a sensor which is positioned in the exhaust section of the car, measures the oxygen content of the car exhaust gases.
This oxygen content, the ‘lambda value’, is a measure for the effectiveness of the combustion process in a car’s engine. The lambda value is transferred to the car engine management system, and - if necessary - the fuel/oxygen ratio to the combustion engine is optimised by adjusting the fuel injection. A research department of a car producer needs to test the performance of these lambda probes with several exhaust gas compositions. To this end, they have built an artificial exhaust line in which they do not use real exhaust gas, but simulate the composition of car exhaust gases. They asked Bronkhorst to deliver mass flow controllers for this purpose
The car producer wants to have the possibility to change the composition from very low content of gases like carbon monoxide (CO) and the nitrogen oxide (NO), to very high contents. Furthermore, they want to change over very quickly to another gas mixture.
- Accurate dosing of exhaust gas constiuents
Initially, Bronkhorst delivered ten mass flow controllers, type EL-FLOW Prestige, for accurately supplying the components of the artificial exhaust gas composition, to stimulate a certain working point. Each specific mass flow controller is meant for a component that may be present in the car exhaust gas (N2, O2, CO, CO2, NO, hydrocarbons, sulfur compounds etc.) These individually generated gas flows enter a mixing chamber, and when the flow is stable it is fed to the lambda probe.
With the EL-FLOW Prestige mass flow controllers it is possible to incorporate small amounts of gas into the artificial exhaust gas mixture. Several ranges were used, and the mass flow controllers were calibrated from 9 milliliters per minute to 20 liters (N2 gas) per minute.
To perform more lambda probe tests in the same amount of time, in a later stage the research department requested Bronkhorst to deliver a second set of ten EL-FLOW Prestige mass flow controllers, to simulate another working point in parallel. At the same time that the Lambda probe was tested using an artificial exhaust gas composition from the first train, the composition of the second train was premixed in the second mixing chamber. In this way, they could changeover from one working point to another, by physically (dis)connecting each of the mixing chambers to (from) the lambda probe, saving time.
This solution was chosen because of high flexibility because of high flexibility, and because of high accuracy. This setup has to be flexible, as the real working points (compositions) do indeed vary. But also to be prepared for different compositions in the future, if compositions or effectiveness may change.
El Flow Prestige FG-201CV
- Min. flow 0, 14... 7 mln/min
- Max. flow 0, 4...20 ln/min
- Pressure rating 64 bar
- 100 select-able gases
- Customized I/O configurations