NUEVO MÉTODO CONSERVATIVO PARA LA SIMULACIÓN DE LA TRANSFERENCIA DE CALOR EN MUROS MULTICAPA BASADO EN PERFILES DE TEMPERATURA PARABÓLICOS Y FACTORES DE RESPUESTA

[EN] The most popular programs building energy simulation and more used are based on the method of response factors (REF) (Mitalas & Stephenson, 1967) to assess the thermal energy demand of buildings. It is sampled with a certain fixed frequency temperature on both sides of an enclosure and between different sampling instants supposed evolution was linear. This interpolation is known as forming element (EF) or holder of the sampled signal of order 1. For the temperature on each side is needed to take stock of thermal power on both surfaces of the enclosure. This leads to the balance of power is true in the sampling instants but not outside of them and therefore no calculation scheme conserves energy. The stated objective is to obtain a method of fast and accurate simulation. The scheme should retain the power to allow the making jumps when internal loads or other excitations and the action of air conditioning systems. HVAC dynamics is rarely considered and its response time is faster than the building, so the sampling time of one hour is maintained. The proposed methodology demonstrates how to apply the method of response factors using a second order polynomial. All under a scheme that conserves energy within the sampling points. The parabolic profile can fulfill this condition between sampling points. To check the validity of the method results from the linear function and the proposal function with the same sample rate and comparing different. As discussed, it is concluded that there is greater precision in temperature and the energy transferred to the air. This thesis proposes to replace it, the trainer of order 1 with another element of order 2. To shape the evolution of temperatures on each side of the enclosure, in addition to the balance of powers balance of power is required so the scheme calculation is conservative. The proposed method gives a similar increase the sampling frequency with a lower precision computation time. Therefore, it is intended through this thesis lay the theoretical and methodological basis of a new model for calculating heat transfer in walls to meet the current needs of accuracy and speed in the process of designing both buildings but especially new and existing renovation strategies.[ES] Los programas de simulación energética de edificios más conocidos y empleados utilizan el método de los factores de respuesta (REF) (Mitalas & Stephenson, 1967) para evaluar la demanda de energía térmica de los edificios. Se muestrea con cierta frecuencia fija la temperatura a ambos lados de un cerramiento y entre instantes de muestreo distintos se supone que su evolución fue lineal. Esa interpolación se conoce como elemento formador (EF) o sostenedor de la señal muestreada de orden 1. Para obtener la temperatura a cada lado se necesita hacer un balance de potencias térmicas en ambas superficies del cerramiento. Esto lleva a que el balance de potencia sea cierto en los instantes de muestreo pero no fuera de ellos y por lo tanto el esquema de cálculo no conserva la energía. El objetivo planteado es obtener un método de simulación más rápido y preciso. El esquema debe conservar la energía para permitir la toma de saltos por hora de las cargas internas u otras excitaciones y la acción de los sistemas de climatización. La dinámica de HVAC es rara vez considerada y su tiempo de respuesta es más rápido que el edificio, por ello se mantiene el tiempo de frecuencia de muestreo de una hora. La metodología propuesta demuestra cómo aplicar el método de los factores de respuesta mediante un polinomio de segundo orden. Todo ello bajo un esquema que conserva la energía dentro de los puntos de muestreo. El perfil parabólico permite cumplir esta condición entre los puntos de muestreo. Para comprobar la validez del método se comparan resultados entre la función lineal y la parabólica propuesta con la misma frecuencia de muestreo y distinta. Como se expondrá, se concluye que existe una mayor precisión en la temperatura y la energía transferida al aire. La presente tesis propone substituir pues, el elemento formador de orden 1 por otro de orden 2. Para dar forma a la evolución de temperaturas a cada lado del cerramiento, además del balance de potencias se requiere el balance de energía por lo que el esquema de cálculo es conservativo. El método propuesto permitirá una precisión similar a aumentar la frecuencia de muestreo con un tiempo inferior de cálculo. Por tanto, se pretende a través de la presente tesis sentar la base teórica y metodológica de un nuevo modelo para el cálculo de la transferencia de calor en muros para dar respuesta a las necesidades actuales de exactitud y rapidez en el proceso de diseño tanto de edificios nuevos pero especialmente de los existentes y sus estrategias de rehabilitación.[CA] Els programes de simulació energètica d'edificis més coneguts i empleats utilitzen el mètode dels factors de resposta (REF) (Mitalas & Stephenson, 1967) per avaluar la demanda d'energia tèrmica dels edificis. Es mostreja amb certa freqüència fixa la temperatura a banda i banda d'un tancament i entre instants de mostreig diferents se suposa que la seva evolució va ser lineal. Aquesta interpolació es coneix com a element formador (EF) o sostenedor del senyal muestreada d'ordre 1. Per obtenir la temperatura a cada costat es necessita fer un balanç de potències tèrmiques en amb dues superfícies del tancament. Això porta al fet que el balanç de potència sigui cert en els instants de mostreig però no fora d'ells i per tant l'esquema de càlcul no conserva l'energia. L'objectiu plantejat és obtenir un mètode de simulació més ràpid i precís. L'esquema ha de conservar l'energia per permetre la presa de salts per hora de les càrregues internes o altres excitacions i l'acció dels sistemes de climatització. La dinàmica de HVAC és rares vegades considerada i el seu temps de resposta és més ràpid que l'edifici, per això es manté el temps de freqüència de mostreig d'una hora. La metodologia proposada demostra com aplicar el mètode dels factors de resposta mitjançant un polinomi de segon ordre. Tot això sota un esquema que conserva l'energia dins dels punts de mostreig. El perfil parabòlic permet complir aquesta condició entre els punts de mostreig. Per comprovar la validesa del mètode es comparen resultats entre la funció lineal i la parabòlica proposta amb la mateixa freqüència de mostreig i diferent. Com s'exposarà, es conclou que existeix una major precisió en la temperatura i l'energia transferida a l'aire. La present tesi proposa substituir doncs, l'element formador d'ordre 1 per un altre d'ordre 2. Per donar forma a l'evolució de temperatures a cada costat del tancament, a més del balanç de potències es requereix el balanç d'energia pel que l'esquema de càlcul és conservatiu. El mètode proposat permetrà una precisió similar a augmentar la freqüència de mostreig amb un temps inferior de càlcul. Per tant, es pretén a través de la present tesi asseure la base teòrica i metodològica d'un nou model per al càlcul de la transferència de calor en murs per donar resposta a les necessitats actuals d'exactitud i rapidesa en el procés de disseny tant d'edificis nous però especialment dels existents i les seves estratègies de rehabilitació.Soto Francés, L. (2016). NUEVO MÉTODO CONSERVATIVO PARA LA SIMULACIÓN DE LA TRANSFERENCIA DE CALOR EN MUROS MULTICAPA BASADO EN PERFILES DE TEMPERATURA PARABÓLICOS Y FACTORES DE RESPUESTA [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/60924TESI

Strategy for the energy renovation of the housing stock in Comunitat Valenciana (Spain)

[EN] The Spanish residential building stock built between 1940 and 1980 period presents a high energy saving potential as it represents a significant percentage of the total housing stock and it was built without any regulation regarding energy efficiency. Accordingly, the first aim of this paper was to quantify the energy saving potential and the related reduction in CO2 emissions of the housing stock in those years. The work focuses on the Mediterranean climate of the Comunitat Valenciana Region, therefore the energy efficiency strategies proposed are passive and deal with the envelope of buildings. On the basis of the results obtained, several scenarios with intervention periods of 10, 20 and 30 years were calculated. The conclusion was that with the current rate of annual building renovation, it will be nearly impossible to reach the goals established by the EPBD. Only a deep transformation of the building fabric within this sector could help in achieving them. Finally, it should be noted that the proposed methodology can be applied to other areas with different climates, particularly in Spain. (C) 2016 Elsevier B.V. All rights reserved.This research has been supported by the Valencia Government - Conselleria of Housing, Public Works And Territorial Structure, by the research institute Valencia Institute of Building (IVE) and by the Intelligent Energy Europe Programme of the European Union through EPISCOPE project.Serrano Lanzarote, AB.; Ortega Madrigal, L.; Garcia-Prieto Ruiz, A.; Soto-Francés, L.; Soto Francés, VM. (2016). Strategy for the energy renovation of the housing stock in Comunitat Valenciana (Spain). Energy and Buildings. 132:117-129. doi:10.1016/j.enbuild.2016.06.087S11712913

Método mejorado para el cálculo de la transferencia de calor en muro multicapa. Aplicación en rehabilitación

A popular method to obtain the 1-D conduction heat transfer of multilayered plane geometries is attributed to Stephenson and Mitalas (1971) and Mitalas (1968). It is applied in different forms known as; CTF (Conduction Transfer Functions) or RT (Response factors). Roughly his idea consists in sampling the temperature at each side of a wall at a certain fixed time step (usually one hour). Between sampling points, due to the lack of information, a linear profile for the evolution of those temperatures is imposed. A triangleshaping function is used to get such a piecewise linear profile. The paper proposes an improvement by extending the idea of a shaping function. Instead of assuming a linear evolution, a specially designed second order (parabolic) evolution is enforced.This paper describes the use of the methodology of transient 1D heat transfer in multi-layered walls with a hold element of 2nd order, and applies it to a specific situation with the most common constructive solutions used in Spain in the energy refurbishment field .The methodology is applied to several constructive refurbished solutions that include insulation as improvement. The results obtained are compared with traditional methods and the greater accuracy of the present method is shown. Finally it shows how the traditional 1st order holder presents worst approximations to reality when the enclosure has more inertia and the insulation is placed at the face where the disturbance is caused.Los programas de simulación energética de edificios más conocidos y empleados utilizan el método de los factores de respuesta (REF) (Mitalas & Stephenson, 1967) para evaluar la demanda de energía térmica de los edificios. Se muestrea con cierta frecuencia fija la temperatura a ambos lados de un cerramiento y entre instantes de muestreo distintos se supone que su evolución fue lineal. Esa interpolación se conoce como elemento formador (EF) o sostenedor de la señal muestreada de orden 1..Este artículo propone substituir el elemento formador de orden 1 por otro de orden 2. El presente artículo expone la utilización de la metodología de transferencia de calor en un cerramiento multicapa con un elemento formador de 2º orden, y aplicarlo a una situación concreta con los cerramientos más frecuentes utilizados en España en el campo de la rehabilitación energética. Igualmente se analiza la aplicación a dichos cerramientos una vez rehabilitados con diferentes posibilidades de incluir aislamiento en dichos cerramientos. Se comparan los resultados obtenidos y se demuestra la mayor precisión que se obtiene con esta nueva metodología. Finalmente se demuestra que un elemento formador de 1º orden presenta peores aproximaciones a la realidad cuando el cerramiento tiene mayor inercia y cuando el aislamiento se realiza en la cara donde se provoca la perturbació

MedZEB: a new holistic approach for the deep energy retrofitting of residential buildings

The MedZEB (Mediterranean Zero Energy Building) approach aims at stimulating the market uptake of energy deep and beyond retrofitting of existing buildings of the Mediterranean. Its holistic nature implies the evaluation and integration of a range of relevant factors and the effective support to the retrofitting supply chain, also with the help of an ICT platform. Main concern of the approach are residential buildings within a framework dealing with High TRL levels and with already on the market technologies to be combined to create Med-specific cost-optimal Packages of technical Solutions, linked to a Voluntary Certification Scheme. The triggered creation of trust and information exchange will pave the way to new investments and strengthen the Med deep and beyond retrofitting network

Scenario Analyses Concerning Energy Efficiency and Climate Protection in Regional and National Residential Building Stocks. Examples from Nine European Countries. - EPISCOPE Synthesis Report No. 3

This report documents methodological aspects and selected results of the scenario analyses to assess refurbishment as well as energy saving processes and project future energy consumption.. It covers scenario calculations conducted for regional residential building stocks in Salzburg/Austria, the Comunidat Valenciana/Spain, the Piedmont Region/Italy, the national non-profit housing stock in the Netherlands as well as the national residential building stocks in Germany, England, Greece, Norway, and Slovenia. Thereby, the objective of the scenario analysis is not a prediction of future energy demand in the respective building stock. Rather, the objective is to show the potential future impact of predefined assumptions. This may help respective key actors and policy makers to decide on strategies and policies for transforming building stocks towards carbon dioxide neutrality

Tracking of Energy Performance Indicators in Residential Building Stocks – Different Approaches and Common Results - EPISCOPE Synthesis Report No. 4

A central task of IEE EPISCOPE project was to carry out energy balance calculations and scenario analysis for national, regional or local residential building stocks against the background of energy saving and climate protection targets. The EPISCOPE Synthesis Report No. 4 documents the individual approaches of collecting information for the investigated residential building stocks as a foundation for building stock models and scenario calculations. Issues related to the availability of data and data quality are discussed, and concepts for a continuous monitoring (a regular data collection) are presented as a basis for a future tracking of energy performance in the observed building stocks

Adelante / Endavant

Séptimo desafío por la erradicación de la violencia contra las mujeres del Institut Universitari d’Estudis Feministes i de Gènere "Purificación Escribano" de la Universitat Jaume

Thermal response factors to a 2nd order shaping function for the calculation of the 1D heat conduction in a multi-layered slab

[EN] A popular method to obtain the 1-D conduction heat transfer of multi-layered plane geometries is attrib- uted to Stephenson and Mitalas (1971) and Mitalas (1968). It is applied in different forms known as; CTF (Conduction Transfer Functions) or RT (Response factors). Roughly his idea consists in sampling the tem- perature at each side of a wall at a certain fixed time step (usually one hour). Between sampling points, due to the lack of information, a linear profile for the evolution of those temperatures is imposed. A tri- angle shaping function is used to get such a piecewise linear profile. The method although is powerful, has passed through the years without questioning. The paper proposes an improvement by extending the idea of a shaping function. Instead of assuming a linear evolution, a specially designed second order (parabolic) evolution is enforced. Now, two parameters must be determined to define the temperature shape between sampling points at both sides of the wall; on one side, the new values of the temperatures and on the other, their acceleration within the time step. Contrary to Mitalas, now two equations are needed at each side to determine these new shapes; the heat power flux balance at both surfaces at the new sampling point (like in Mitalas method) plus the thermal energy balance along the period of time between sampling points. This turns the scheme into an energy conservative one. Finally it is shown that the accuracy obtained by the parabolic case at one hour of sampling rate is similar to the linear case with a sampling rate of five minutes.S5795908

MedZEB: a new holistic approach for the deep energy retrofitting of residential buildings

<p class="Corpo">The MedZEB (Mediterranean Zero Energy Building) approach aims at stimulating the market uptake of energy deep and beyond retrofitting of existing buildings of the Mediterranean. Its holistic nature implies the evaluation and integration of a range of relevant factors and the effective support to the retrofitting supply chain, also with the help of an ICT platform. Main concern of the approach are residential buildings within a framework dealing with High TRL levels and with already on the market technologies to be combined to create Med-specific cost-optimal Packages of technical Solutions, linked to a Voluntary Certification Scheme. The triggered creation of trust and information exchange will pave the way to new investments and strengthen the Med deep and beyond retrofitting network.</p