Field Test of Superheater Pipes Vibration Caused by Sound Energy in the 235 MWe Circulating Fluidized Bed Boiler

This paper presents the results of measurements of vibrations of the pipes of the steam superheater installed in the convection pass of the 235 MWe Circulating Fluidized Bed boiler (CFB) induced using sonic soot blowers of the Nirafon NI-100 type. The measurements were made using two ICP Triaxial 356A16 accelerometers allowing the analysis of accelerations in the maximum range of ±490 m/s2. Simultaneously with vibration measurements, the sound pressure level was recorded using the G.R.A.S. 40BH high-pressure microphone. The measurements and spectral analysis of the recorded signals showed that the acoustic wave of 148 dB is safe for the steam superheater pipes causing vibrations of maximum amplitude not exceeding 1 mm. The field tests confirmed the supposition that the dominant mechanism for cleaning the surfaces of the superheater’s heating pipes are not pipe vibrations, but the breakage of cohesion forces between dust particles.

Diagnostic Protocol for Thermal Performance of District Heating Pipes in Operation. Part 2: Estimation of Present Thermal Conductivity in Aged Pipe Insulation

Buried and operating district heating (DH) pipes are exposed to thermal degradation of their polyurethane (PUR) insulation over time, and their status is hard to assess without excavation. By using DH pipe valves in manholes as measurement points during a shutdown with an ensuing cooling period, non-destructive assessments can be performed. This study compares new improved field measurements with numerical simulations of the temperature decline in drainage valves and shutdown valves. The drainage valve measurements were used to thermally assess part of a buried DH network. Results indicate that by using the drainage valves as measurement points in a cooling method, the thermal conductivity of the buried DH network could be predicted with an accuracy of >95%. In addition, a general diagnostic protocol has been established for assessing the thermal status of a DH network, ready for network owners to use.

Diagnostic Protocol for Thermal Performance of District Heating Pipes in Operation. Part 1: Estimation of Supply Pipe Temperature by Measuring Temperature at Valves after Shutdown

This study evaluates temperatures measured at district heating (DH) valves in manholes and their usability for non-destructively assessing the thermal performance of buried DH pipes. The study was conducted as a field test in which part of a DH network was shut down and the temperature decline in the valves was analysed in terms of absolute temperature and thermal response time from the DH pipe to the top of the valve. The calculated and measured supply pipe temperatures by the drainage valves were in good agreement, with 1% deviation. The valve measurement analysis from this study shows that the drainage valve has good potential to serve as a measurement point for assessing the thermal status of a DH network. However, the shutdown valve measurements were greatly affected by the manhole environment.

Rancang Bangun Rangka dan Pipa Pemanas Pada Mesin Pengering Padi

The climate change in Indonesia results in disruption of the rice drying process which only relies on sunlight for the drying process of rice grains so that during the rainy season farmers having problems on the process of drying rice grains. Thus, a new technology is needed in the process of drying rice grains. This technology is using a rice dryer. In the process of making a rice drying machine, there are several important components that must be designed properly, namely the frame and heating pipes which are the main components of a rice drying machine. The aim of this research was to design the frame and heating pipe for rice drying machines. From the design process, the testing phase is carried out, both machine testing and rice drying testing. The test results show that all machine components run well and the drying results show that the rice has decreased in weight after being put into the rice dryer with decrease is 5 kg to 4,9 kg or about 0,1%.

Optimization of the Geometric Parameters of the Thermal Insulation of the Heating System by Using Multi-Pipe Circular Thermal Insulation

The publication presents a design solution for circular multi-pipe thermal insulation and an example of an existing heating installation consisting of six individual heating pipes in the building of the Bialystok University of Technology. In the paper, the arrangement of six heating system pipes in circular thermal insulation was designed in such a way that one heating pipe is centrally located in the circular thermal insulation, the other five heating pipes are located at the vertices of a regular pentagon inside the circular thermal insulation. Heat loss calculations were made using the Boundary Elements Method (BEM) with the actual boundary conditions in the room where the existing heating installation is located. Additionally, the ecological effect was determined in the form of reduction of pollutants emitted into the atmosphere resulting from heat losses for the developed multi-pipe thermal insulation. The calculation results showed a significant reduction in heat losses as a result of the use of multi-pipe thermal insulation in relation to the existing single heating installation. The use of multi-pipe insulation undoubtedly follows the trend of energy-saving heat transport and is an alternative to the commonly used single pipes.