cooling

This paper describes the unsteady terminal and presents its characteristics gained fromexperiment. The experimental results showed that the fan-coil unit tested in the experimentwas able to provide fluctuating airflow and the velocity curve of supply airflow wasconsistent with the control signal very well. The spectrum of supply airflow is similar to thespectrum of natural wind if the control signal simulating natural wind provided. The supplyair temperature is changed when the airflow is changed.

The influence of uniformly distributed cooling load is investigated on the air velocity in theoccupied zone. The experiments have been carried out in a scaled test room of 6 6 2 mwith a scale factor 1:1.5. The room is equipped with nine vortex inlets. The inlets areuniformly distributed; every inlet supplies a cubical volume to remove the maximum possiblecooling load with a minimum airflow rate. The air supply rates based on floor area are set to30 m/(h m2). The cooling load generated by mannequins is uniformly distributed and variesbetween 0 and 180 W/m2.

A spot cooling system using the convective cooling effect of an air stream is known to beeffective by its smothering intensive hot environment, supplying comfort sense and utilizingenergy efficiently. However, its study on the interaction with human body or product itself isuncommon, showing that the spot cooling system intrinsically contains the possibility ofdraught because of its short emitting distance from the object, low air temperature, high airstream velocity and its direct local contact to human body.

The aim of that study was to demonstrate the potential to design buildings that can simultaneously improve indoor environmental quality along with a reduction of energy. In that order 4 energy-efficient relocatable classrooms were designed and constructed, each equipped with two different HVAC systems (heat-pump air-conditioning system and an energy-efficient indirect/direct evaporative cooler). Results are presented.

The objective of the annex 34 was to develop HVAC fault detection and diagnosis tools, which are closed to commercial products. The approach was to design a number of different computer based demonstration systems that could be interfaced to HVAC processes in buildings. By monitoring the operation of these demonstration systems, researchers were able to test a variety of fault detection and diagnosis methods and technique in a real environment, find possible shortcomings and obtain new ideas for further development.

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.

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).

Dedicated outdoor air systems (DOAS) integrated with ceiling radiant cooling panels as a parallel sensible cooling system are being considered as an alternative to conventional variable air volume (VAV) systems for commercial buildings because of their energy conservation, first and operating costs, and indoor air quality advantages. A pilot DOAS/radiant panel cooling system is being constructed on a university campus to investigate its advantages over alternative cooling systems in

This paper provides a summary of the methods and results of performance testing for a coupled Indoor/Outdoor Environmental Simulator (C-I/O-ES). The simulator consists of an IEQ chamber, a climate chamber, and a replaceable separation/test wall assembly. Both chambers have stainless steel interior surfaces and are equipped with independent heating, ventilating, and air-conditioning (HVAC) systems for simulating indoor and outdoor thermal and air quality conditions, respectively.

The interior zone and exterior zone air-handling units (AHU) can be connected through their return air ducts to become a new air-handling unit system, named OAHU system, which allows optimal choice of outside air intake and decouples sensible and latent cooling in a zone with lower sensible