Gene A Giacomelli

Abstract:

Aqueous foam was developed to serve as a barrier to conductive, convective, and radiative heat transfer. Through the use of a bulking agent, the physical properties of gelatin-based foam were more stable, adhesive, biodegradable, and long lasting. The phytotoxicity, possible environmental hazard and removal of the foam were also considered. Resistance to freezing-thawing, heating-evaporation, and wind were evaluated. Studies to determine the foam's long-term stability under field weather conditions were completed. The handling and performance characteristics of the foam necessary for development of this application were determined. Factors that affect the physical properties and the utilization of the foam were quantified. These included the proportions of the foam components, the mixing temperature of the prefoam solution, the application temperature, and the rate of foam generation. The newly developed foam might be ideal for freeze and frost protection in agriculture.

Abstract:

The energy-balance equation was used to estimate evapotranspiration in a greenhouse, and an instrument was developed to collect data for this purpose. The values estimated by this method were in good agreement with the measured data. It was shown that the net solar radiation term was the largest and cannot be neglected, and that long-wave radiation exchange had a relatively small effect. As usual, soil heat flux can be neglected but the sensible heat transfer term cannot be neglected since the maximum of the possible range of values is large and significant. It was concluded that the method used was simple and suitable for irrigation control in greenhouses. It was also concluded that normal radiation sensor measurements on a horizontal surface are not adequate for measuring radiation received by a plant canopy in a single-span greenhouse. © 2009 IAgrE.

Abstract:

During the period July 2001 to March 2002, the performance of a water-jacketed high intensity discharge lamp of advanced design was evaluated within a lamp test stand at The University of Arizona (UA), Controlled Environment Agriculture Center (CEAC) in Tucson, Arizona. The lamps and test stand system were developed by Mr. Phil Sadler of Sadler Machine Company, Tempe, Arizona, and supported by a Space Act Agreement between NASA-Johnson Space Center (JSC) and UA. The purpose was for long term testing of the prototype lamp and demonstration of an improved procedure for use of water-jacketed lamps for plant production within the close confines of controlled environment facilities envisioned by NASA within Bioregenerative Life Support Systems. The lamp test stand consisted of six, 400 watt water-cooled, high pressure sodium HID lamps, mounted within a framework. A nutrient delivery system consisting of nutrient film technique re-circulation troughs and a storage tank was also included, but plants grown in the system were not evaluated in this time period. The performance of the lamps was quantified in terms of photosynthetic photon flux (PPF), and spectral irradiance during the 9-month testing period. In addition, an energy balance and a series of short term tests were completed on the lamp system. The lamps were operated on a 16 hour 'on' and 8 hour 'off' duty cycle each day. The total operation time for the lamps during the test period was 4208 hour. The following report describes a series of tests performed on the water-cooled high pressure sodium (HPS) lamp system. Copyright © 2003 SAE International.

Abstract:

Even though several models to predict evapotranspiration (ET) of greenhouse crops have been developed, previous studies have evaluated them under fixed greenhouse conditions. It is still not clear which model is more appropriate, accurate, and best suited for applications such as inclusion in greenhouse cooling strategies for different crops, climatic conditions and greenhouse cooling settings. This study evaluated three theoretical models (Stanghellini, Penman-Monteith and Takakura) to simulate the ET of two crops (bell pepper and tomato), under two greenhouse cooling settings (natural ventilation with fog cooling and mechanical ventilation with pad and fan), and for three growing seasons (spring, summer, fall). Predictions of ET from the models were compared to measured values obtained from sap flow gauges. Inputs of internal and external crop resistances for Stanghellini and Penman-Monteith models were calibrated separately by crop and by model. Even though Stanghellini model produced the smallest deviations of the predicted ET from the measured ET, having the best overall performance under all conditions evaluated, an analysis of variance of the daily mean square errors did not show significant differences (α= 0.05) between the three models. This suggested that any of the three models could be used for inclusion in a greenhouse cooling climate control strategy. However, parameter adjustments such as stomatal and aerodynamic resistances, and the need of leaf area index (LAI) in the models of Penman-Monteith and Stanghellini represent a limitation for this application. The Takakura model was found to be easier to implement; however as the crop grows, careful adjustments on the height of the solarimeter used for this approach are required. Such adjustments determine the field of view of the solarimeter and play a significant role on the determination of radiation balances and the average apparent temperature of the evaporative surface. © 2011.

PMID: 11987303;Abstract:

Light intensities on the Martian surface can possibly support a bioregenerative life support system (BLSS) utilizing natural sunlight for hydroponic crop production, if a suitable controlled environment can be provided. Inflatable clear membrane structures offer low mass, are more easily transported than a rigid structure, and are good candidates for providing a suitable controlled environment for crop production. Cable culture is one hydroponic growing system that can take advantage of the beneficial attributes of the inflatable structure. An analog of a Mars inflatable greenhouse can provide researchers data on issues such as crew time requirements for operation, productivity for BLSS, human factors, and much more at a reasonable cost. This is a description of one such design.