Heat Transfer Model for Blade Twist Actuator System

Abstract

DOI: 10.2514/1.23120 A lumped mass heat transfer model is developed for a blade twist actuator system that uses thermally activated shape memory alloys to alter the shape of a wing. These alloys are coupled with thermoelectric modules that supply the heat necessary to activate the shape alteration characteristics of the material. The model predicts the unsteady temperatures in different portions of the actuator system, and comparisons between experimental data and the heat transfer model are made. Furthermore, parametric studies are made of system variables to optimize the numerical model, and the effect of each variable on the comparison is examined. Differences between the numerical and experimental models are discussed, and efforts are made to minimize this difference through variations in the numerical variables. The potential for using this technology to increase range and payload of aircraft is discussed. Nomenclature cp = specific heat, J=kg K h = convective heat transfer coefficient, W=K I = electrical current, A N = number of thermoelectric modules in row n = number of time steps q = heat flow, W R = electrical resistance, � T = temperature of thermal zone or atmosphere, C t = time, s � = Peltier coefficient, V=K � t = time step, s � = thermal conductivity, W=K