Optimal air distribution design in enclosed spaces using an adjoint method

2 Wei Liu, Qingyan Chen* 3 4 a School of Mechanical Engineering, Purdue University, West Lafayette, IN 47907, USA; 5 b School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, 6 China 7 8 This investigation studied an adjoint method to achieve the optimal design of ventilation in 9 an enclosed environment and validated it with two, two-dimensional cases. A part of the 10 flow field and/or temperature field was defined as the design objective, and the thermo-fluid 11 boundary conditions were determined as the design variables. By using the adjoint method 12 together with a steepest descent method that was implemented in OpenFOAM, this 13 investigation found the optimal air supply parameters. With the determined air supply 14 parameters, this study used CFD to calculate the flow and/or temperature fields, which are in 15 a good agreement with the design objective. However, as the adjoint method could only find 16 the local optima, the calculations with different initial inlet air conditions may lead to 17 multiple optimal solutions. This is common with the gradient-based method. 18 19