Assessment of the performances of a heat exchanger in a light helicopter

Abstract

This study has the aim to develop a numerical design regarding the position and the inner performances of a heat exchanger in a light helicopter. the problem was to find first of all the best position of the heat exchanger inside the engine vane in order to maximize the air flow rate capable to pass through the heat exchanger section. It is to be said that the only air contribution in the vane comes from the opening present in the roof under the main rotor. The design has been performed by means of the commercial code Fluent and using the well known grid generator ICEM CFD. Different positions are first investigated so to establish the best one. Subsequently, different areas of the opening on the roof have been considered in order to maximize even more the flow rate in the heat exchanger that was not sufficient based on the first guess of velocity, as aforementioned. At the end interesting design results are presented and discussed by contours of fields and values.

Heat Exchangers in the Aviation Engineering

“…• StarCCM+, They include packages able to simulate the flow fields inside the tubes and also specific numerical models capable of simulating special fluids like nanofluids or special structures like porous media [23][24][25][26].…”

“…The relationship between the mass flow rate _ m and pressure drop ∆p in the cooler can be put in a similar shape, see the values shown in Table 2 where Δn is the HE total length in the flow direction, ρ is the air density, and μ is the air dynamic viscosity, see papers [23][24][25][26]. By using the aforementioned values, one can simulate the external and internal flow fields with respect to the cooling ducts and find the numerical air flow rate passing through the heat exchanger.…”

“…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 number of certification tests and the related cost, see also paper [25]. Table 2.…”

Experimental and Numerical Investigation of Convection Heat Transfer in an Enclosure With a Vertical Heated Block and Baffles

“…They reported that natural convection and flow field are significantly affected by (Ra) and fin thickness. Carozza [18] developed a numerical model to simulate air flow through a heat exchanger inside the engine vane of a helicopter. The best place of heat exchanger is found to be near the lower exit on the rear to increase the air flow rate.…”