In engine and vehicle development, the air volume and humidity must be provided under defined conditions. Since the intake air depends significantly on engine size, load condition and ambient conditions, precise and stable humidity control is required. For this purpose, STASTO implemented a finely adjustable valve solution for the exact dosing of air humidity in the test process.
At a glance
- Industry: Engine and vehicle development
- Application: Air conditioning and humidity dosing of the intake air
- Medium / Process: Air / defined humidification in test bench operation
- Challenge: Precise adjustment and reproducibility of humidity under variable operating conditions
- STASTO solution: Combination of slide valve and microvalve in split-range operation
- Result: Very high control accuracy and stable process control
The challenge
In test benches for engines and vehicle components, the intake air must be precisely defined in terms of quantity and humidity. The air humidity influences combustion processes, emission behavior, and performance parameters.
The intake air depends on several factors: engine sizing, load condition, and external ambient conditions. These parameters change dynamically and must nevertheless be adjustable in a reproducible manner.
Standard solutions with only roughly sized valves or simple control concepts reach their limits here. Particularly with low humidity additions, very sensitive dosing is required, while at higher load conditions larger volume flows must be reliably controlled. A solution was therefore required that operates precisely in both the lower and upper control range and enables stable integration into the test bench technology.
The STASTO solution
To achieve the required moisture dosing, a valve combination consisting of a slide valve and a micro valve was used. Both valves were operated in split-range mode so that different control ranges could be specifically covered.
The micro valve is responsible for high-precision dosing in the lower flow range. For larger flow rates, the sliding gate valve is activated. This graduated control strategy made it possible to achieve very fine resolution across the entire operating range.
The valve selection was carried out taking into account the required control characteristic, the dynamic requirements, and the integration into the existing automation concept. The actuation was designed in such a way that a reproducible transfer between the control ranges is ensured.
In close coordination with the machine or test bench manufacturer, the solution was integrated both mechanically and in terms of control technology. Particular attention was paid to safe integration into the existing process environment as well as to good maintenance accessibility of the components.
The result
By combining a slide valve and a micro valve, a very high control accuracy could be achieved. According to the project description, controllability in the range of 1:1000 was feasible.
The solution enables stable and reproducible test conditions in continuous operation. Fluctuations in ambient conditions can be specifically compensated.
In addition, the early technical coordination during the planning phase led to swift implementation. The structured integration process reduced project effort and coordination time.
Added value for machine builders
- Precise humidity control over a wide operating range
- Reproducible test conditions for development and testing processes
- Clear separation between fine and coarse dosing
- Good integrability into existing automation systems
- Maintenance-friendly valve technology
This solution is particularly suitable for
- Engine test benches
- Vehicle test benches
- Climate and environmental test systems
- Development and test facilities
- Applications with high control resolution
Contact
Are you planning a system with precise requirements for your media control and process stability?
Talk to our experts – we will be happy to advise you.