Contribution to Active Thermal Protection Research—Part 1 Analysis of Energy Functions by Parametric Study

Abstract

The thermal energy consumption for heating objects is one of the main parameters deciding their technical and structural solution. Reducing energy consumption is realized in various ways. The most used method is passive thermal protection, that is, increasing the thermal insulation parameters of the envelope constructions and optimizing the operation of the technical equipment of the buildings. There are also methods of active thermal protection to reduce heat leakage through non-transparent parts of the building envelope. Active thermal protection (ATP) is a dynamic process that applies primarily to building structures with integrated energetically active elements that fulfill one or more functions in mutually exclusive operating modes of energy systems and heat sources, such as thermal barriers (TB), large-scale heating/cooling, long-term heat/cool storage, capturing solar energy, and energy from the surroundings or even recovering heat in the cold season or cold in the warm season and other combinations. The research area focuses on analyzing active thermal protection’s energy potential. The methodology is based on a parametric study of dynamic thermal resistance (DTR), and heat flows to the interior and exterior from ATP for the investigated envelope of the experimental house EB2020 made of aerated concrete blocks. Such constructions generally show a consistently high DTR of 11.8 to 30.8 ((m2·K)/W) at a low mean heat transfer temperature of 10 to 16 °C, corresponding to the thermal insulation of 300 to 1000 mm. In the case of ATP storage heating with an average temperature of the heat-carrying substance of 30 °C, the heat flow into the interior of the investigated structure would be only 2.31 W/m2. Therefore, they are only suitable for a thermal barrier and heat/cold accumulation. Based on the synthesis and induction of analogical forms of the results of previous research into recommendations for the design of individual energy functions of ATP for perimeter structures of buildings, we present heat flows to the interior/exterior when changing the material of the layers towards the interior from ATP and describe possible variants of the development of building structures with integrated energetically active elements.

Keywords

• parametric study
• integrated energy-active elements (IEAE)
• dynamic thermal resistance (DTR)
• active thermal protection (ATP)
• thermal barrier (TB)
• wall heating/cooling