Cordierite Ceramics Prepared from Poor Quality Kaolin for Electric Heater Supports: Sintering Process, Phase Transformation, Microstructure Evolution and Properties

To efficiently utilize the kaolin, an economical way of preparing cordierite ceramic with high performance for electric heater supports was put forward. In this study, sintering process, phase transformation, microstructure evolutions were systematically studied by heating microscope, X-ray diffraction, scanning electronic microscope and thermal analysis. Properties（physical properties, electrical properties and coefficient of thermal expansion（CTE）） were tested for comprehensive performance evaluation. The results showed that the utilization of poor quality kaolin broadened the firing range of cordierite ceramic which was from 1 200 to 1 380 ℃. Microstructure becomes loose with increasing of the pore size, which had significant influence on bending strength and electrical properties. High content of K2 O in poor quality kaolin was the reason for liquid phase generation in sintering process, which further leads to microstructural changes. The cordierite ceramic sintered at 1 320 ℃ had the properties as follows： CTE of 1.98×10^（-6） ℃^（-1）（500 ℃）, bending strength of 90 MPa, apparent porosity of 15.1%, dielectric constant of 7.5（100 Hz）, and volume resistivity of 1.05×109 Ω·cm（100 Hz）. The comprehensive properties are very suitable for use as electric heater supports.

Optimisation of Electrical Distribution System by Using Solar Thermal Powered Systems and Its Impact on Electrical Distribution Feeders

In this research, the performance of the solar thermal powered systems (STPS) is analyzed with different models (without inserts, with inserts and with Nano fluids with different concentrations) and its impact on the Electric load in a residential/Institutional Electrical Distribution system. For this purpose, the electrical and solar thermal water heater is tested and validated. Solar thermal powered systems and its impact on the Institutional electrical distribution feeders are tested and compared with the energy efficiency (EE) and cost optimization. The goal of this paper is to analyze the impact of solar thermal energy on electrical energy consumption in the electrical distribution feeder level. The electrical system cost and energy consumptions are tabulated and observed that there is a considerable savings.

MPC-based interval number optimization for electric water heater scheduling in uncertain environments

In this paper,interval number optimization and model predictive control are proposed to handle the uncertain-but-bounded parameters in electric water heater load scheduling.First of all,interval numbers are used to describe uncertain parameters including hot water demand,ambient temperature,and real-time price of electricity.Moreover,the traditional thermal dynamic model of electric water heater is transformed into an interval number model,based on which,the day-ahead load scheduling problem with uncertain parameters is formulated,and solved by interval number optimization.Different tolerance degrees for constraint violation and temperature preferences are also discussed for giving consumers more choices.Furthermore,the model predictive control which incorporates both forecasts and newly updated information is utilized to make and execute electric water heater load schedules on a rolling basis throughout the day.Simulation results demonstrate that interval number optimization either in day-ahead optimization or model predictive control format is robust to the uncertain hot water demand,ambient temperature,and real-time price of electricity,enabling customers to flexibly adjust electric water heater control strategy.