Nomenclature

3.2. Compact heat exchangers choice for a light helicopter

Table 2. Characteristic values of the heat exchanger taken into consideration.

162 Heat Exchangers– Advanced Features and Applications

number of certification tests and the related cost, see also paper [25].

Figure 6. Light helicopter side view with heat exchanger locations.

grid generator.

Often the choice of the heat exchanger positioning can be crucial in a life of a helicopter. In the following, a number of simulations are presented tailored to the best cooler location for a light helicopter. The flow equations are solved by means of a finite volume code and a structured

Mass flow rate m\_ [kg/s] Pressure drop Δp [Pa] Heat eject Q\_ [kW]

0.1 220 200 0.2 356 300 0.3 520 450 0.4 720 550 0.5 860 650

Three positions for the heat exchanger location have been investigated by a thermal point of view as shown in Figure 6. Each position is characterized by a specific value of air flow rate. In order to maximize the flow rate and taking into account also maintenance problems, the manufacturer chooses to locate the cooler near the opening after the engine because the cooler is crossed by a mass flow rate able to cool the engine and can be inspected by the maintenance team. Using the same methodology of the previous paragraph, the designer, in a simplified manner, and without knowing the constructive details of the heat exchanger, can so take preliminary decisions about the size and the positioning of the heat exchanger reducing the


