Open-Roof Greenhouse

A Subambient Open Roof Surface under the Mid‐Summer Sun

A novel material open to warm air stays below ambient temperature under maximum solar intensities of mid-summer. It is found to be 11 °C cooler than a commercial white cool roof nearby. A combination of specially chosen polymers and a silver thin film yields values near 100% for both solar reflectance, and thermal emittance at infrared wavelengths from 7.9 to 13 μm.

Heat Pump Cooling and Greenhouse Microclimates in Open and Confined Greenhouse Systems

The purpose of this study was to determine and compare the performances of conventional and heat pump systems for cooling open and closed loop (confined) greenhouse systems. A dynamic simulation model was developed and validated to predict energy and mass exchanges in a greenhouse as a function of dynamic environmental factors. The model has options to evaluate the effects of location, time of ...

Roof Rats

Effect of the open roof on low frequency acoustic propagation in street canyons

This paper presents an experimental, numerical and analytical study of the effect of open roof on acoustic propagation along a 3D urban canyon. The experimental study is led by means of a street scale model. The numerical results are performed with a 2D Finite Difference in Time Domain approach adapted to take into account the acoustic radiation losses due to the street open roof. An analytical...

Retractable roof structures

j This paper presents a new concept for retractable roof structures. The new structures consist of a foldable lattice of beams connected by cylindrical joints, to which covering panels or membranes are attached. These structures fold towards their perimeter and there is practically no limit to their shape. Solutions to the key problems that have to be solved in the course of the kinematic desig...