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Aiming at the problem that salt mist seriously affects the reading performance of radio frequency identification (R FID) tags, the salt mist effects on the performance of RFID tags are researched through simulation and measurement. The reading range of RFID tags in the salt mist environment is reduced because the boundary conditions of the test chamber reduce the antenna efficiency and gain. As the concentration of the salt mist in the test chamber increases, the environmental conductivity in the test chamber increases, and the RFID reading distance of the tag decreases. In this paper, a theoretical formula is proposed for calculating RFID reading distance in salt mist environment. Besides, RFID dynamic identification based on the salt mist environment platform is designed. Corresponding functions are obtained by fitting the experimental data. This function establishes the relationship between salt mist concentration and the RFID reading distance. The experiment shows this theoretical formula is feasible, and the system has high practicability. At the same time, the system shows that the reading distance decreases as long as the concentration of the salt mist increases.

The ASTM G134 standard, Standard Test Method for Erosion of Solid Materials by Cavitating Liquid Jet, provides specifications for assessing the material resistance to the cavitation erosion caused by submerged cavitating jet. Nevertheless, the influence of test chamber dimensions on cavitation erosion is not considered in such an international standard. To fill in the gap, nine test chambers with different chamber lengths and diameters were devised to facilitate a comparative investigation of the cavitation aggressive intensity. The cavitation number was fixed at 0.014. Aluminum (JIS A1070) and stainless steel (JIS SUS316L) specimens were used in the experiment. The results show that at the distance of 19 mm between the nozzle outlet section and the specimen surface, the most severe erosion is accomplished, which is shared by the nine test chambers. Both the mass loss and the erosion rate vary with the test chamber length and diameter. A long test chamber is associated with a low erosion rate. The coefficient of variation on the cumulative erosion rate is 12 %. As the chamber length equals the chamber diameter, the coefficient of variation is 3 %. At the test chamber length of 30 mm and diameter of 40 mm, the maximum erosion rate is higher than its counterparts. The present study provides important data for the ASTM G134 standard to decide the operation parameters and test chamber dimensions.

A wind generator is used for producing a wind stream equivalent to the required wind velocity pressure for dynamic water penetration tests for curtain walls. A two-phase experimental program was carried out. In the first stage, the calibration of the wind generator was conducted following AAMA 501.1-05 procedures. In the second stage, the dynamic pressure distribution on the surface of the test chamber for curtain walls was studied. Discussions of the experimental results are presented, as well as new design aids for curtain wall design. Some of the experimental results and conclusions could be useful in the future for comparisons between laboratories having similar electric-fan-based test systems.

A round-robin study of two coupon cleaning methods as implemented by five different laboratories has been completed. The results show that measuring the change in mass of copper coupons is an effective and practical technique for quantifying the reactivity of test chamber environments. Since the coupon cleaning and preparation method appears to affect the gravimetric data, a well defined and consistent method is required to obtain useful results.

A method for evaluating the performance of air barrier systems for building enclosures is described. It is proposed that two identical enclosure elements be placed back-to-back and, for airtightness purposes, be joined to each other by the same techniques which join the element to the structure itself. This way, by taking advantage of symmetry, virtually all joints not found in actual applications can be eliminated, barring easy-to-seal joints associated with air supply or exhaust and pressure tap lines. Three applications of the approach with associated test results are presented. It is suggested that the proposed test procedure has the following advantages over single-specimen tests in conjunction with a test chamber: specimen size and shape are not restricted, samples can be saved for future testing after suitable aging procedures, specimens can be tested outdoors or in a controlled environment chamber, and virtually all extraneous joints can be eliminated. A disadvantage is that two specimens may have to be prepared.

Fracture mechanics tests were conducted on a 2¼Cr-1Mo steel in an environment containing 6% hydrogen sulfide and 94% hydrogen at temperatures up to 727 K (850°F) and pressures to 24.1 MPa (3500 psi). A test chamber and accompanying system were designed to test under monotonically rising, sustained, and cyclic loads. This paper contains a description of the design and operation of the system developed to conduct these tests, along with a brief discussion of testing experience and types of results.