2.1.2. Measurement Devices

Piezo resistive pressure sensors and K-type thermocouples were used for measuring pressure and temperature of the gas along the exhaust system (see Figure 2). The exhaust mass flow rate was calculated from the addition of fuel and air mass flow rates. Skin temperatures used in calculations were provided by the IR camera Gobi-384 GigE.

**Figure 2.** Sketch of the exhaust with measurement points involved in the development of the model. The exhaust system is 4 m long and pipe has a diameter of 5 cm (figure not to scale).

Pollutants are measured using an ENVIRONNEMENT manufacturer equipment. A TOPAZE 32M model was used as NOx analyser, based on the chemiluminescence effect from NO oxidation by ozone (O3). The GRAPHITE 52M gas analyser measures total hydrocarbons (THCs) by flame ionization detection while a MIR 2R gas analyser measures CO and CO2 species, detecting the molecules absorption in the infrared spectrum. Other species compositions are estimated via chemical balances from fuel and air consumption.
