Emissions - Decreasing Fuel Consumption and Exhaust Gas Emissions in Transportation - page 83

exhaust gas shaft

filler engine air flow exhaust gas

exhaust gas pipe

- stressed wires
- sampling point
- stainless steel gas pipe

measuring unit

Fig. 5.2 Test bench for the control of jet engines emissions

The exhaust gas can be taken via a stainless steel gas pipe behind the engine in
the exhaust gas pipe.
The measurement devices are basically the same for vehicles, airplanes, and
ships.

• Chemo Luminescence Detector (CLD) for NO x , NO, and NO 2 ;
• Flame Ionization Detector (FID) for HC;
• Fourier Transformation Infra Red (FTIR) spectrometers for CO and CO 2 ; and
• Opacimeters, and filter-based or photo acoustic methods for smoke and particle
measurements.

5.2.2 Measurement On-Board

In all means of transportation sensors are used for recording data. Sensors convert
physical or chemical parameters into an electric signal on a miniature scale. The
analog input signals may be steadily linear, steadily nonlinear, or repeatedly
stepped. The output signals are current, tension, amplitude, frequency, etc., which
are analog and can be changed to a binary digital form [ 19 ].
The common mechanical, physical, chemical, electrical, magnetic, and climatic
conditions in vehicles, airplanes, and ships define the placement of sensors. Sen-
sors must:

• Steer, brake, and protect all operational processes if necessary;
• Monitor the engine, transmission, undercarriage, wheels, and tires; and
• Inform the driver or the captain of the performance, the fuel consumption, and
the emissions.