New Type of Valve for Solar Thermal Storage Tank Stratification

Abstract

This paper describes the working principle and characteristics of a new type of valve with a unique self-actuating principle that actuates based on observed temperature difference, which is intended for use on solar thermal storage tank inlets, where it compares the temperature of the flow coming into the valve with the temperature inside the storage tank, and switches the flow based on the observed temperature difference, in order to achieve maximum thermal stratification inside the storage tank. The novel working principle, based on mass-transfer inside the actuator driven by vapour pressure differences, is explained in detail, and results of tests with the valve are presented, which show that the valve switches very effectively, and is a very useful tool for storage tank stratification.