A 2D transient heat transfer model to predict the electrical power output of a TEG system on a car. This would model the waste heat recovery potential of a Heat Pipe assisted TEG system.
It employs Eigen, a C++ template library for linear algebra: matrices, vectors, numerical solvers, and related algorithms. Check their website: http://eigen.tuxfamily.org/index.php?title=Main_Page The Eigen::BiCGSTAB<Eigen::SparseMatrix > method was used to solve the equations.
In the input_data folder there are all the variables that are relevant for the simulation. In the cycle folder there's the driving cycle used for this simulation, a WLTP template is provided. The engine conditions necessary to fulfil the driving cycle are predicted using a steady-state engine model map, from which the exhaust mass flow and temperature are extracted. The file cycle.csv is an example of the thermal output of a driving cycle.
In the file: app_root_dir; should be the path to where the code is in your machine. In the folder input_data\controlVars there are the main variables the can be modified.
A finned cooler was simulated m_cooler - Water cooler mass flow [kg/s] Nc - Number of flow channels in the cooler channel_widt - Channel widt [m] fin_widt - fin widt [m] fin_heigt fin heigt [m] channel_length - channel_length [m] lateral_length - transversal length [m] Metal_tick - cooler thickness from the base of the fins to the TEG module [m] number_of_coolers - number of coolers [m] Twater_in - inlet water temperature [K]
An offset fin Heat exchanger was simulated in this example. s - fin spacing [m] h - fin height [m] tick - fin thickness [m] l - offset length [m] number_of_channels - number of channels [m] number_of_offsets - number of offsets [m] L_HP - Heat Pipe length [m] T_TEG_MAX - Maximum TEG temperature [K]
selectTEG 1 k_HE k_HP cp_HP density_HP density_HE k_cool cp_cool density_cool Tamb rhoDense_leg_TEG Tau_P Tau_N alfa_connector_TEG k_connector_TEG cp_connector_TEG density_connector_TEG rho_connector_TEG k_cer_TEG cp_cer_TEG density_cer_TEG
dx - x discretization [m] dy - y discretization [m] dt - time discretization [s] delta_x - TEG discretization [m] write_increment - time step to write results [s] initTemperatureField - initial temperature of the system [K] error_tol - maximum error allowed max_iter - maximmum number of iterations
n_leg - number of TEG legs leg_side_N - N type TEG side length leg_side_P P type TEG side length leg_length - leg length L_Al_connector connector thickness Lcer ceramic thickness voidPercentage_TEG - empty space percentage between modules