Simplified analytical model to describe wind loads and wind-induced tracking deviations of heliostats

Article Energy & Fuels

Full-scale investigation of heliostat aerodynamics through wind and pressure measurements at a pentagonal heliostat

Kristina Blume et al.

Summary: Wind loads on heliostats are often investigated through experimental wind tunnel studies or numerical simulations. However, these approaches cannot consider the full-scale conditions but require a reproduction and simulation of both the heliostat structure and the wind conditions. Complementary full-scale investigations are therefore crucial but are at the same time relatively costly, as it is cumbersome to set up large heliostats with measurement devices. This paper introduces a new pressure measurement system which is easy-to-apply to a real-scale heliostat and enables full-scale investigations with minimized effort. The results of a first field study are presented during which wind and pressure measurements were taken simultaneously over periods of 10 min at a 48.5 m² pentagonal Stellio heliostat. The non-dimensional pressure distributions are investigated and it is shown that the mean cp-values are very consistent amongst the measurement periods and reach values between 2.2 and 2.6. These values, in turn, are found to agree well with results of a wind tunnel study. Moreover, the behavior of the load coefficients with varying angles of attack is studied and the aerodynamic admittance functions are evaluated which give in-depth insight into the generation of aerodynamic loads. The admittance functions are found to start decreasing at a non-dimensional frequency of approximately 0.2. This finding indicates that eddies which are about the size of the heliostat or larger are fully effective in generating aerodynamic loads while the effectiveness of smaller eddies is reduced.

SOLAR ENERGY (2023)

Add to Collection

Proceedings Paper Energy & Fuels

Status Update of the SolarPACES Heliostat Testing Activities

Marc Roeger et al.

Summary: This paper provides an update on the progress of the three guidelines being developed by the SolarPACES task III-heliostat working group, which aim to standardize the performance testing of heliostats and heliostat fields in solar power tower systems. These guidelines are intended to be included in international standards and used by national organizations in the field of solar power.

SOLARPACES 2020 - 26TH INTERNATIONAL CONFERENCE ON CONCENTRATING SOLAR POWER AND CHEMICAL ENERGY SYSTEMS (2022)

Add to Collection

Review Energy & Fuels

A review of static and dynamic heliostat wind loads

Matthew Emes et al.

Summary: Accurate estimation of wind loads on heliostats based on detailed turbulence measurement is crucial for structural integrity and cost reduction. Wind load predictions are not specified due to non-standard shapes and varying wind conditions in the ABL. Increased understanding of aerodynamic effects and wind load predictions would improve field efficiency models and reduce costs.

SOLAR ENERGY (2021)

Add to Collection

Review Energy & Fuels