Investigation of thermohydraulic dispatcher properties and peculiarities

Abstract

Application of thermohydraulic dispatcher (THD) for district heating systems is, to some extent, limited due to insufficient information about its properties and features. At the same time this device has a potential to solve the problem of mutual dependence of heat consumers and to decrease electricity consumption in heat supply systems. This paper deals with experimental research and numerical simulation of THD with the aim of increasing the range of knowledge about its properties. Presented results describe already known properties such as near-to-zero differential pressure at THD and flow rates independence which were checked. Some new properties and peculiarities of THD were obtained during the investigation as well. Among them is differential pressure "variability", hydrodynamic separation under higher velocity, similarity of thermohydraulic processes inside THD under similar velocities in manifolds of THD, absence of thermal stratification in mixing regime, dependence of secondary circuits supply temperature from the height level and secondary circuits return temperature.

Hydraulic and thermal characterization of a family of thermo-hydraulic separators

“…Thermal stratification is often claimed to be a positive, yet qualitative, feature for a thermal-hydraulic separator device [25,19]. The proposed stratification index SI, Eq.…”

“…A recent experimental and numerical study by Romanov and Yavorovsky [19] compares the temperature drop from HS to HC for both the in-line and the staggered connection of the manifolds.…”