Testing heat supply networks for heat losses

Abstract

The scope of operations of the branch where the survey was carried out is: transmission and distribution of heat and heating medium to consumers through heat supply networks, maintaining the proper quality and amount of thermal power and heating medium supplied, ensuring contractual activities with heat consumers, as well as control of compliance with the consumption regimes stipulated by contracts, ensuring payments from consumers for supplied heat and heating medium, development and implementation of measures ensuring maximum efficiency of heat supply activities. The purpose of the work performed is to determine the actual heat losses through the thermal insulation of the surveyed heating networks and to compare them with normative values. The article presents an analysis of materials on the heat supply system; test findings for actual heat losses in a heat supply pipeline; calculation of actual heat losses for each section and their adjustment to average annual operating conditions of the given heat supply network; comparison of calculation results with normative characteristics. The test findings are used in developing the output performance for the «Heat Loss» indicator and in setting of norms for operating heat losses. The heat supply source for the heat pipeline is the CHP-plant. The pipelines are routed above ground on high and low supports, as well as in crawl ways. The thermal insulation of the pipelines is mainly made of 50 mm blankets of mineral wool and is typical for heat supply networks. In overhauls of heat supply networks, polyurethane foam is partly used as thermal insulation.

Experimental Assessment of the Thermal Conductivity of Basalt Fibres at High Temperatures

“…The behaviour of insulating materials for high-temperature supply systems, such as district heating networks, has received increasing interest [3]. Field tests found that the actual heat losses exceed the standard values by 1.21-1.35 times in heat networks [3].…”

“…The behaviour of insulating materials for high-temperature supply systems, such as district heating networks, has received increasing interest [3]. Field tests found that the actual heat losses exceed the standard values by 1.21-1.35 times in heat networks [3]. These results emphasise the need to develop durable materials with a stable behaviour even at temperatures of several hundred Celsius degrees.…”