Tightness monitoring camera for critical parts of rural technological and scientific equipment

There are a lot of devices, including rural equipment with a high level of tightness. Nowadays, a wide range of methods are used for investigation and testing: capillary, radiographic, radio wave, mass spectrometric, eddy current, surface-active substances, etc. These methods require special equipment and do not allow continuous monitoring during operation. The traditional soap solution coating can continuously monitor the tightness until drying. Thus, there is a problem in creating an easy and robust method of monitoring the tightness of the critical equipment parts during the operation. In this work, a new method for the tightness control is proposed. It is based on the principle of distributing flows in parallel piping. If the camera around a critical part is sealed, its leaks will have high aerodynamic resistance. Therefore, if a small hole (0.1-1 mm) is made in such a camera, its aerodynamic resistance will be some order smaller. Since the distribution of flows is inversely proportional to the square of the specific characteristic of aerodynamic resistance, the main outflow or inflow due to leakages in the critical part inside the camera will occur almost through this hole, which is easy to register. This camera has been used in the Laboratory of Heat-Mass Exchange in Green Structures to test gas exchange in plants. For testing the method, the fan in the test stand before final sealing is slowly accelerated until the signal appears. After that, the flow rate has been estimated using a collector. The results show a very high sensitivity. In the collector, the anemometer showed only 0.02 m·s-1. The confidence interval of the flow is 0-0.019 m3·h-1. However, the anemometer reading near the hole is 0.43, which is a very clear signal. The signal will be clear at the leakage of 0.0086 m3·h-1. The soap coating of all junctures and smoke visualisation did not show a leakage place. This allows recommending the camera for the most critical equipment parts.