## 6 Experimental Research  
To validate the precision and dependability of the finite element and analytical techniques proposed in this research for modeling a porous aerostatic rectangular thrust bearing, an experimental investigation was conducted. The purpose of this investigation was to identify the optimal structural configuration and to select a suitable manufacturing technique for producing porous gas static-pressure rectangular thrust bearings that adhere to experimental standards. The bearing's static performance was assessed through rigorous experimentation, and the outcomes were evaluated against the simulations. Consistency between the bearing capacities identified through finite element and analytical methodologies with those observed in experimental settings under identical operational conditions would confirm the effectiveness of the methods introduced in this study. The apparatus for measuring the carrying capacity of aerostatic thrust bearings is depicted in Figure 20. An air pump delivers adjustable and consistent high-pressure air to both the bearing and the loading cylinder, allowing the bearing's working surface to hover between the platforms. The rod of the loading cylinder is linked to a tension pressure sensor, ensuring that steady force is exerted on the bearing, which is quantified by this sensor. Concurrently, the gap of the bearing's gas film is determined using an inductance micrometer. Due to the many factors that can affect the measurement results, including auxiliary part machining errors, sensor installation errors, environmental vibrations, and fluctuations in the gas supply, each parameter was measured five times, and the value of each parameter was compared with the theoretical analysis results. Load capacity experiments were conducted on a rectangular bearing characterized by 0.2 mm diameter throttle holes and a length of 40 mm. Four distinct supply pressures, 0.3, 0.4, 0.5, and 0.6 \(\,\)Mpa, served as the baseline for assessing variations in load-bearing ability relative to the thickness of the gas film. Experimental findings were subsequently  
Figure 19: Influence of the length \(a\) of the rectangular orifice array on the stiffness. Figure 18: Influence of the gas supply pressure on stiffness. juxtaposed with outcomes derived from finite element and analytical predictive techniques, all of which are documented in the graph in Figure 21.  
The results of the study revealed a correlation between theoretical analysis and experimental data. It was observed that under varying pressures, the outcomes from the experimental groups aligned with trends predicted by both finite element methods and analytical approaches. Analytical approaches demonstrated closer congruence to finite element methods with minimal discrepancies. The differences observed could be attributed to the adoption of a turbulence model in finite element analysis, predicated on the vortex viscosity assumption. Conversely, discrepancies with experimental observations were due to simplifications made in the model by both finite element and analytical methods, leading to certain inaccuracies. Across the four sets of supply pressures, it was noticed that discrepancies were minimal at smaller gaps between experimental data, finite element outcomes, and analytical results. However, as the thickness of the gas film increased, the  
Figure 21: Comparison of the bearing capacity results of a porous aerostatic rectangular thrust bearing: (**a**) 0.3\(\,\)Mpa; (**b**) 0.4\(\,\)Mpa; (**c**) 0.5\(\,\)Mpa; and (**d**) 0.6\(\,\)Mpa. Figure 20: Experimental apparatus. divergence between experimental measurements and predictions from finite element and analytical methods gradually widened. This variance could likely stem from experimental procedures that obtained gas film thickness by altering load conditions in contrast to the approaches of finite element and analytical methods. The largest discrepancies under the four supply pressures, both for finite element and experimental methods, were noted for the 18 \(\upmu\)m gap.