Energy analysis of the thermal comfort

A thermal comfort designer is especially concerned with creating an environment to improvethe physical, mental and psychical health of human beings. The general thermal state of thebody both in comfort and in heat or cold stress is dependent on an analysis of the heat balancefor the human body. Traditional methods of thermal analysis are based on the first law ofthermodynamics. By contrast, the second law of thermodynamics introduces the usefulconcept of exergy in the analysis.

Ventilation, Humidity Control and Energy : A Tightrope of Challenges and Opportunities

This paper is a keynote address presented at Ventilation, Humidity Control and Energy 24th AIVC Conference.It is a warning for HVAC professionals that are however walking a tightrope. How provide sufficient ventilation for IAQ that yet maintain an appropriate moisture balance without using excessive energy ?Mold is having a severe impact upon us; excessive ventilation and reducing the energy to control the humidity are oftentimes being blamed. Claims have skyrocketed for mold , mildew and humidity-related problems cases.

Summing-up of the 24th AIVC conference

This is a personal set of comments giving the author's impressions of the papers presented at the conference. A great concern of him is the difference between building scientists and health scientists as indoor air quality issues are investigated.

Two-objective online optimization of supervisory control strategy

The set points of supervisory control strategy are optimized with respect to energy use and thermal comfort for existing HVAC systems. The set point values of zone temperatures, supply duct static pressure, and supply air temperature are the problem variables, while energy use and thermal comfort are the objective functions. The HVAC system model includes all the individual component models developed and validated against the monitored data of an existing VAV system.

Technical and economical interest of sustainable refurbishment technologies in France, Italy and Finland

The aim of the European SSHORT (Sustainable Social Housing Refurbishment Technologies) project is to increase and promote rational and efficient use of energy in the retrofitting of social housing buildings. In this scope, one step was to evaluate with simulation studies the technical and economical interest of selected sustainable technologies on standard collective social housings in participating countries.

Combined thermal measurement and simulation for the detailed analysis of four occupied low-energy buildings

This paper describes four simulation models, which reproduce energy and temperature measurements of occupied buildings very well. These buildings represent small to medium size residential low-energy buildings of different construction type, which are typical for mid-Europe. For the simulation, the software TRNSYS is used. The reproduction of measured energy and temperatures in time steps of 15 minutes is well suited for precise predictions on heating energy demand and comfort of the buildings and modifications of them.

Indoor air quality and energy issues of refrigerant modulating air-conditioning systems in the tropics

Due to its simplicity in installation and maintenance on the one hand, and to its potential to conserve energy on the other hand, the refrigerant modulating air-conditioning system has become very popular. This paper presents the results of an IAQ energy audit of two buildings in Singapore that use that kind of system. The results are compared to those obtained from conventional air-conditioning systems.

System interactions in forced-air heating and cooling systems. Part 2 : continuous fan operation

The purpose of continuous fan operation is to bring in fresh outdoor air to the conditioned space in order to maintain acceptable indoor air quality. Ventilation not only uses more energy, but it also impacts air distribution system efficiency.This is partially due to various system interactions. The objective of this paper is to quantify the impact of continuous fan operation on energy use and distribution efficiency by introducingtwo new parameters: energy use ratio (EUR) and distribution efficiency ratio (DER).

Infiltration and natural ventilation model for whole building energy simulation of residential buildings

The infiltration term in the building energy balance equation is one of the least understood and most difficult to model. For many residential buildings, which have an energy performance dominated by the envelope, it can be one of the most important terms. There are numerous airflow models;
however, these are not combined with whole building energy simulation programs that are in common use in North America. This paper describes a simple multizone nodal airflow model

Integration of airflow and energy simulation using CONTAM and TRNSYS

The impact of infiltration and ventilation flows on energy use in commercial buildings has received limited attention. One of the reasons for this lack of study is that the commonly used programs for estimating the energy use of buildings do not incorporate the interzonal airflow modeling techniques
required to adequately account for the effect of these factors on energy usage. To address this issue and provide insight into the impact of these flows, the CONTAM airflow modeling tool