Prediction methodology for transient thermal response of solar parabolic trough collector under fluctuating solar radiation

Solar parabolic trough collector technology is an effective way to utilize solar thermal energy, which reduces the carbon dioxide emission. Although the weather in Malaysia and other Southeast Asian countries is suited to solar thermal applications for the long daytime that continues all year around. Still, the fluctuation in solar radiation caused by the high humidity must be handled when estimating the thermal performance of the parabolic trough collector application. To perform transient thermal simulation to incorporate the effect from the solar radiation fluctuation, long calculation time and large memory space are required when the existing numerical methods are used. A simple but powerful methodology to predict the time dependent parabolic trough collector tube exit temperature is proposed. In this methodology, the exit working fluid temperature is estimated by superimposing the temperature rise caused by each heat flux pulse that forms the solar radiation. The preliminary results and methodology improvement for more realistic prediction conditions are discussed