| Water leakage of a wall may cause a building's structure failure and loss of energy efficiency, and may also lead to unhealthy indoor living environment. With the walls'weight lightening reform, the rain leakage problem begins to be bothersome for the light-weighted walls. The pressure equalized rain-screen (PER) walls were exactly proposed in this context. The PER walls' water-tightness performance is more reliable, compared to the single-line barrier walls, the drained cavity walls, and the simple rain-screen walls. Based on the inner layer's air tightness and the outer layer's intentional openings, a PER wall's cavity will be divided into several compartments to achieve a more percentage of pressure equalization across its outer layer.Considing the problems and shortages on the study of the PER walls'pressure equalization, such as:the frequency-domain solution of the pressure transfer and its precision, the law of the parameters' influence, the impact of the wind pressure's spatial correlation, the scaling similarity criterion of modeling in the wind tunnel test, this study carried out as follows:Firstly, the frequency-domain solution of pressure transfer for the PER walls with flexible non-leaky air barrier was deduced based on linearation. And the accuracy of the frequency-domain solutions for the PER walls above-mentioned and the PER walls respectively with rigid leaky air barrier or rigid non-leaky air barrier was tested at conventional conditions by solving typical examples. Case calculations verified that the frequency-domain solution of pressure transfer for those three kinds of the PER walls is applicable, and the precision of those solutions meets the project requirements well.Secondly, to understand the law of the parameters' influence on the PER walls'pressure equalization under wind excitation more in-depth and comprehensively, analysis was carried out in a semi-theoretical semi-empirical way based on the symbolic derivative of the pressure transfer function of the frequency-domain solution and combined with some nesessiry checking by case calculations. Base on that, the PER walls' water-tight design can be guided more effectively.Thirdly, in order to simulate the influence of the wind pressure's spatial correlation on the PER walls'pressure equalization more truly, continuous calculation models for four kinds of pressure drop, such as:the pressure drop at the opening, the space average pressure drop across the rain-screen, the pressure drop at some point on the rain-screen, and the pressure drop across compartment seal, were deduced. Meanwhile, discrete calculation models and their simplied algorithms were derived based on continuous calculation models to achieve fast algorithms. Those models can simultaneously consider the dynamic characteristics of the PER walls and the wind correlation. Besides that, the calculation models under the quasi-static approximation of the PER walls' pressure transfer were also deduced. Moreover, by case calculations, the accuracy of the simplied algorithms and the effectiveness of the models under the quasi-static approximation of the pressure transfer were examined; the formation mechanism and the change law of those four pressure drops were analyzed.Fourthly, based on some related control equations, the scaling similarity criterion for the PER walls' modeling in the wind tunnel tests was derived. The applicability of the Helmholtz resonator model in the study of the PER walls' pressure equalization was analyzed. And the control equations for the pressure transfer were normalized by introducing a characteristic length and a characteristic velocity. Then the similarity parameters were obtained, and the similarity factors of relevant parameters were determined. Besides that, the realizability of the similarity criterion for the PER walls' modeling in actual wind tunnel tests was investigated. And the impact of some modeling error to the test results was inspected by numerical solution based on control equations.
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