Development and performance evaluation of a novel cost-effective multifunctional fluid tunnel: from coastal atmospheric boundary layer simulation to coupled wind-wave experiments

Recently, a well-designed, cost-effective, multifunctional fluid tunnel (BRJL-MFT) has been constructed, under the support of Belt and Road Joint Laboratory (BRJL), to serve various types of fluid experiments related to environment and engineering in coastal and ocean regions. One of its features is that it contains an expanded test section compared to the overall tunnel dimensions. The aerodynamic characteristics in the empty tunnel confirmed that its performance meets the benchmarks of other classical fluid tunnels. Subsequently, a full-depth atmospheric boundary layer (ABL) of the coastal region was further reproduced using triangular spires and cubic roughness elements. Test results presented as mean velocity, turbulence intensity, integral length scale of turbulence and power spectral density of velocity fluctuations were compared with the expected theoretical models. Moreover, a coupled wind-wave experimental facility was developed by integrating a wave generator and a wave absorber. Preliminary experimental evaluations have demonstrated that the developed facility is capable of effectively producing wind-wave environment, enabling both fundamental studies of wind–wave interaction and scaled model experiments in ocean engineering applications. In summary, the cost-effective and compact design of the BRJL-MFT makes it a highly adaptable and broadly applicable solution for environmental and engineering research in coastal and ocean regions.