PowerPoint Presentation

Studies on Heat Transfer Augmentation of Phase Change Materials for Building Cooling ApplicationsGuided By: Dr. N Lakshmi Narasimhan

1. Goutham L2. Inti Sandeep3. Dularish K A IntroductionPhase Change materials are used in heat storage systems due to their latent heat storage capacity. At high temperature, PCMs absorb heat equal to their latent heat capacity, they melt into liquid. Whereas at lower temperature, they solidify liberating heat stored. Melting process is also known as charging period and solidifying process is also known as discharging period.Phase Change materials could help us to find a way to store heat energy when its available in excess and utilize it, so that it paves a way for the creation of energy efficient environmental friendly buildings.

ObjectivesTo study on the heat transfer characteristics of Phase Change materials when incorporated in building materials.To build an experimental setup and conduct studies for feasibility of application for a particular climatic condition.MotivationThe rising demand for energy in buildings and increasing environmental consciousness necessitates exploration of energy-efficient methods and effective utilization of energy.Close to 40% of all energies produced get consumed in household buildings, hence they present an opportunity for reducing energy consumption.ChallengesSelection of PCM: There are a wide variety of PCMs ranging from organic paraffin and non paraffin to inorganic PCMs each having distinct advantages and disadvantages. They also vary in their operating temperatures and latent heat storage value so, for a specific climatic condition, PCM has to be selected such that they complete their charge-discharge cycles.Incorporation: Various choices are available such as mixing of micro-encapsulated/ macro-encapsulated PCM which are done during the production of building materials. Alternatively Phase Change Frame Wall can be built, again each method has its own advantages and disadvantages.Numerical Modeling: Due to the presence of phase change phenomenon, its challenging to solve numerically.Summary of Literature SurveyJournalsAuthorsContentEnergy and BuildingsN.Soares, J J Coasta, A.R. Gasper [2013]Review of passive PCM latent heat thermal energy storage systems towards buildings efficiencyEnergy and BuildingsV.V Tyagi, D. Buddhi, Richa Gothari, S. K Tyagi [2012]Phase Change Material based thermal management system for cool energy storage application in building: An experimental studyEnergy and BuildingsRuben Baetens, Bjorn Petter Jelle, Arild Gustavsen [2010]Phase Change materials for building applications : A state of the art reviewRenewable and sustainable energy reviewsAntoni Gil, Marc Medrano , Ingrid Martorell, Ana Lazaro, Pablo Dolado [2010]State of the art on high temperature thermal energy storage for power generation. Concepts, materials and modellizationMethodologyExperimental setup: A rectangular box made up of plywood/gypsum board is to be created within which a wall enhanced by encapsulated PCMs is built. Insulation around the entire cubicle is to be provided with glass wool.Material Used: Encapsulated PCM is mixed with concrete in a determined amounts. The multi-phase mixture is known as PCM-Concrete. In case of difficulty, separate pipe is provided in the walls and encapsulated PCMs are placed inside. This type of wall is known as Phase-Change frame wall (PCFW).Heat Source: A number of electric bulbs are positioned around a side of wall for varying heat flux.Recording: The thermal properties are recorded for varying composition of mixtures using thermocouples.Current statusWe have started to learn Ansys workbench and have attempted a simple problem consisting of a single brick in Transient thermal.However, we would like to study melting and solidification phenomenon which is possible in Ansys Fluent. We are in the learning stages.We are planning to start constructing the cubicle within a week.

Expected Outcome

We are planning to build a cubicle like the one above in the picture and conduct experiments on PCM incorporated building materials placed inside. Material with which it is to be made is not finalized yet but it should necessarily be insulated with materials like glass wool.Thank You