Isaac Guedi Capeluto

Thermal mass and night ventilation as passive cooling design strategy

We calculated the influence of thermal mass and night ventilation on the maximum indoor temperature in summer. The results for different locations in the hot humid climate of Israel are presented and analyzed. The maximum indoor temperature depends linearly on the temperature difference between day and night at the site. The fit can be applied as a tool to predict from the temperature swing of the location the maximum indoor temperature decrease due to the thermal mass and night ventilation. Consequently, the fit can be implemented as a simple design tool to present the reduction in indoor temperature due to the amount of the thermal mass and the rate of night ventilation, without using an hourly simulation model. Moreover, this design tool is able to provide for the designer in the early design stages the conditions when night ventilation and thermal mass are effective as passive cooling design strategy.

The influence of the urban environment on the availability of daylighting in office buildings in Israel

Abstract The main goals of the present work are to investigate the influences of the built environment on the potential use of daylighting in office buildings in Israel, and to offer a simple design method for architects during initial design stages to assess the daylighting potential of the building site. A typical office building under different surrounding built layouts has been modeled and simulated using Sustarc and Radiance. Parametric simulations have been performed to estimate the influence of different obstruction patterns on the daylighting performance of the office. The availability of daylighting has been shown to be approximately proportional to the sky solid angle (SSA) subtended from the center of the window. The proposed methodology can help designers evaluate and understand the possibilities of using natural lighting from the early conceptual design stages when different design alternatives are being considered as well as adapt the building design for the existing surrounding conditions.

On the use of ‘solar volume’ for determining the urban fabric

Abstract An exhaustive analysis for the determination of the urban fabric is carried out by implementing a computerized model SustArc. The model evaluates the maximum allowed ‘solar volume’ to be built without preventing solar access from each building and from the open spaces during a predefined period of the year. For every urban configuration, the model calculates the obtained urban density. The results show that it is possible to achieve high density urban quarters without violating any solar rights. Optimized urban fabric solutions are presented.

Climatic aspects in urban design—a case study

We present a case study of a design of a new business district in Tel Aviv city. In this work climatic aspects were taken into consideration in the very early design stages. For that purpose, two models SustArc (Proceedings of the ISES 1997 Solar World Congress, Taejon, Korea, 1997, p. 148) and FLUENT 5.0.2 (Fluents Users Guide, Fluent Inc., NH, USA, 1999) were applied in order to achieve solar and wind rights. The new business district was designed as a high-density urban area and is located near an old low-rise residential quarter. SustArc was used as a design tool to create the solar envelope that shows the maximum available volume in which it is possible to build without violating the solar rights of existing residential neighborhood, the main avenues and the pedestrian sidewalks. FLUENT, on the other hand, was implemented as an evaluative tool, in a trial and error method, until a design solution could be achieved, in which the wind rights of the residential neighborhood were preserved, while ensuring tolerable winds inside the business district. The paper presents the process of sun and wind controlled planning, as well as the recommendations.

Simulations and knowledge-based computer-aided architectural design (CAAD) systems for passive and low energy architecture

Abstract This paper describes a methodology for supporting computationally all phases of an energy-conscious design and evaluation process, by combining procedural simulation and knowledge-based heuristic methods in one integrated system. Based on this methodology knowledge-based computer-aided architectural design systems for the design and evaluation of solar and low-energy buildings are presented. The knowledge-base contains the heuristic rules for the design of passive solar buildings. Whenever possible, the knowledge-base guides the designer through the decision-making process. Yet, if the rules of thumb are not acceptable for the particular design problem, the knowledge-based system guides the architect by using procedural simulation models.

What are the required conditions for heavy structure buildings to be thermally effective in a hot humid climate

We calculate the influence of thermal mass and night ventilation on the reduction of the maximum indoor temperature in summer in residential buildings without using air-conditioning. The results are given for different locations in the hot-humid Mediterranean climate of Israel. We found that the maximum obtained indoor temperature reduction depends linearly on the temperature difference between day and night at the site. The results obtained show that one can predict the indoor temperature decrease, due to the thermal mass and night ventilation, from the simple and available data of the long term average temperature swing of the site, which is a common available data. The conclusion is that in the hot-humid climate of the Mediterranean coast, high thermal mass with night ventilation is effective for residential buildings with no air-conditioning provided the temperature swing is above 5°C, which is in general the case in this climate.

Non-Linear Architectural Design Process

The introduction of the computer to the architectural design process have facilitated the possibility to examine a large number of design alternatives by allowing continuous variation between pre defined constraints. However, for the most part, evaluation and comparison of the alternatives is still handled manually in a linear fashion by the designer. This paper introduces a different approach to the architectural design process, which calls for a multithreaded or a non-linear design process. In a non-linear design process design directions and alternatives are generated, presented and evaluated simultaneously, and in real time. As an example for a non-linear design process the Generative Performance Oriented Design model and software tool (GenPOD) are presented and discussed. Moving towards non-linear modes of design arguably increases design creativity by allowing generating and evaluating a greater number and variation of design alternatives.

Computer-Based Form Generation in Architectural Design - a Critical Review

The idea of using computers for form generation and evaluation in the architectural design process has been put forward already in the early days of computers. However, as opposed to computer aided drafting, the generation of form, its optimization and manufacturing has not been widely accepted and implemented by practitioners. The paper critically reviews the research and state of the practice experiments that has been done in this field and develops an argument regarding the possibilities and limitations of computer-based form generation in the architectural design process.

A method for the generation of climate-based, context-dependent parametric solar envelopes

ABSTRACT This paper proposes a method and a tool for determining maximum building heights in an urban setting while maximizing solar access. Expanding upon previously conducted ‘solar envelopes’ research, a flexible and advanced filtering mechanism based on weather data, site geometry and mixed programmatic requirements is introduced and the concept of parametric solar envelopes is presented. In order to make the proposed method widely accessible, it is released as an open-source tool as part of the Ladybug analysis tools suite in Rhino/Grasshopper. As a case study, a comparison of simulated solar envelopes based on varying requirements in an urban context is presented and the qualitative and quantitative advantages compared to existing methods are discussed. It is expected that this method and its practical implementation will inform the early design stages and provide meaningful feedback which will contribute to environmentally conscious design and healthier, more sustainable environments.

External shading in buildings: comparative analysis of daylighting performance in static and kinetic operation scenarios

ABSTRACT The paper presents a new enumerative method and tool to quantify and compare the potential contribution of kinetic and static external shading elements in buildings, in terms of dynamic measurement of daylighting. The suggested method and tool may help designers to examine the impact of various louver design and operation alternatives in the early stages of the design process. It also allows comparing the potential contribution of different dynamic louver movement scenarios to internal illuminance. This can help designers to better evaluate and compare different dynamic systems, which can be more cost effective. The method and tool are tested on a case study of an office building in a Mediterranean climate, by calculating and comparing the values of useful daylight internal illuminances in static, seasonally adjusted and dynamic louver setup scenarios in comparison to those without louvers. The results of the case study illustrate the contribution of the suggested method and tool to designing for high useful daylight levels. The case study’s illuminance evaluation shows an increase of −1.82% to 7.99%, −1.4% to 11.67% and 10.86% to 33.6% in level of the adapted useful daylight illuminances in static, seasonally adjusted and dynamic external shadings scenarios correspondingly in comparison to the no external shading scenario.