Thermal Method for Non-Destructive Control of Actual Coolant Mass Flow through a Heating Device

Denis Karpov,Anton Sinitsyn,J Smyatskaya

doi:10.1051/e3sconf/202016101041

Abstract

The studies show that expenses for heating buildings and structures account for more than 60% of total utility costs in the Russian Federation. Therefore, the issues on energy and resource conservation and improving the energy efficiency of construction projects for various purposes are relevant and priority. Infrared thermography is actively used during examination of thermomechanical equipment, building structures, external and internal engineering systems and their elements. Heat monitoring makes it possible to avoid significant costs for dismantling of controlled objects and to localize the thermal defects found during the inspection stage, thereby reducing costs of repair works. The article considers and analyzes the existing options for the quantitative analysis of thermograms. The authors propose a new method for quantitative processing of thermograms, aimed at assessing the operation of heating devices in heating systems of buildings and structures. The essence of thermal non-destructive testing technique is to determine the actual mass flow rate of coolant through the heating device.

Highlights

Quantitative analysis of thermograms is based on calculation of local relative (with respect to the basic section) heat transfer resistances [1]
Where τbi and τbe are the temperatures of internal and external surfaces of the building envelope in the reference zone, respectively, °C; q is the heat flux density, W/m2
Calculation of thermal resistance to heat transfer of the required section of building envelope Rreq is carried out according to the analytical expression: Rreq = Ravb(τbe - te)/(τreqe - te), m2·K/W, (4)

Summary

Introduction

Quantitative analysis of thermograms is based on calculation of local relative (with respect to the basic (reference) section) heat transfer resistances [1]. The relative heat transfer resistance R(х, у) at a selected point on a building envelope surface is calculated for internal (1) and external (2) inspections: R(х, у) = 1 + (θ(х, у)/(ti - τbi - θ(х, у))), (1)

Results

Conclusion