Thermal and Geometrical Assessment of Parabolic Trough Collector Mounted Double Evacuated Novel Receiver Tube System

Abstract

This paper particularly aims to highlight the necessity of optimal geometric design considerations of a parabolic trough collector (PTC) mounted novel receiver tube in view of efficient operation and high-end performance. Many investigations, analysis, and validation have been done in this regard as solar energy based PTC now a commercially mature technology acknowledges a variety of role in the form of power generation and other thermal applications. This article identifies the optimal rim angle corresponding to its tube size as required for high exergetic gains. Almost six receiver tubes, distinct in terms of dimensions and number of covers are compared for their best results to be mounted on adequate geometry with different rim angle (40°, 80°, and 120°). A significant variation of flow rate (i.e. 16 to 216 litre/hr) and inlet fluid temperature (i.e. 323 K, 423 K, 523 K, 623 K, and 723 K) has been extensively detailed about high energy and exergy retrieval from the system. The study reports that all the favorable results are found with the receiver tube having a diameter of 0.027 m and a double envelope, compared to other design considerations. Results show that as the flow rate increases energy efficiency also increases up to some extent along with increasing receiver tube temperature. The highest energy and exergy efficiency as reported to be 79.4% and 47% respectively with 80o being the optimal rim angle for a 5.7 m wide parabolic aperture.