Catalogue Search | MBRL
Are you sure you want to remove the book from the shelf?
{{itemTitle}}
15,851
result(s) for
"Heat Experiments."
Sort by:
Experiments with heat and energy
Discover scientific principles by carrying out step-by-step activities, and learn how to conduct fair tests and to record and assess results.
Book
Experimental Performance Study of a Transcritical CO2 Heat Pump Equipped with a Passive Ejector
This study is dedicated to an experimental investigation of a passive two-phase ejector used as an expander in a transcritical CO2 heat pump. The investigation focused on the impact of the evaporating temperature (Tevap) and the CO2 gas cooler outlet temperature (Tgc-out) on the ejector and the overall cycle performance. The basic cycle without an ejector was also tested as a baseline for comparison. Two ejectors designed with different modeling approaches were tested and compared. The ejector with an enlarged mixing section diameter was selected for subsequent testing due to its improved pressure lift. The optimum primary nozzle position was found to be 4 times the mixing section diameter (Dmix). Although the ejector was designed for specific conditions, the results demonstrate its ability to remain operational under varying conditions with some changes in performance. The ejector’s performance was observed to be dependent on the Tevap, and particularly on the Tgc-out. The pressure lift recorded was in the range of 3.7-6.5 bar, and the lowest value was obtained with the low Tgc-out value (29 °C). Under the tested conditions, the integration of the ejector enhances the performance and the capacity of the heat pump. The ejector cycle improvement is primarily based on improved mass flow rates due to increased compressor suction pressure, reduced compression ratio, and consequently, improved compressor operating conditions. Improvements of up to 18% in heating COP and 20.5% in heating capacity were observed. The study provides valuable insights into enhancing the performance of transcritical CO2 heat pump system by refining ejector design. It explores the behavior of the system across varying conditions, highlighting the significant impact of the ejector-compressor interaction on overall performance.
Journal Article
Experiments with heat and cold
Presents several experiments with heat and cold and discusses thermodynamics.
BOOK
Thirty years of coral heat-stress experiments: a review of methods
For over three decades, scientists have conducted heat-stress experiments to predict how coral will respond to ocean warming due to global climate change. However, there are often conflicting results in the literature that are difficult to resolve, which we hypothesize are a result of unintended biases, variation in experimental design, and underreporting of critical methodological information. Here, we reviewed 255 coral heat-stress experiments to (1) document where and when they were conducted and on which species, (2) assess variability in experimental design, and (3) quantify the diversity of response variables measured. First, we found that two-thirds of studies were conducted in only three countries, three coral species were more heavily studied than others, and only 4% of studies focused on earlier life stages. Second, slightly more than half of all heat-stress exposures were less than 8 d in duration, only 17% of experiments fed corals, and experimental conditions varied widely, including the level and rate of temperature increase, light intensity, number of genets used, and the length of acclimation period. In addition, 95%, 55%, and > 35% of studies did not report tank flow conditions, light–dark cycle used, or the date of the experiment, respectively. Finally, we found that 21% of experiments did not measure any bleaching phenotype traits, 77% did not identify the Symbiodiniaceae endosymbiont, and the contribution of the coral host in the physiological response to heat-stress was often not investigated. This review highlights geographic, taxonomic, and heat-stress duration biases in our understanding of coral bleaching, and large variability in the reporting and design of heat-stress experiments that could account for some of the discrepancies in the literature. Development of some best practice recommendations for coral bleaching experiments could improve cross-studies comparisons and increase the efficiency of coral bleaching research at a time when it is needed most.
Journal Article
Junior scientists. Experiment with heat
This book introduces simple scientific principles involving heat, and provides instructions for experiments that can be conducted by children.
Book
Effects of in situ experimental warming on metabolic expression in a soft sediment bivalve
Ocean surface temperatures and the frequency and intensity of marine heatwaves are increasing worldwide. Understanding how marine organisms respond and adapt to heat pulses and the rapidly changing climate is crucial for predicting responses of valued species and ecosystems to global warming. Here, we carried out an in situ experiment to investigate sublethal responses to heat spikes of a functionally important intertidal bivalve, the venerid clam
Austrovenus stutchburyi
. We describe changes in metabolic responses under two warming scenarios (five days and seven days) at two sites (muddy and sandy). Tidal flat warming during every low tide for five days affected the abundance of multiple functional metabolites within this species. The metabolic response was related to pathways such as metabolic energetics, amino acid and lipid metabolism, and accumulation of stress-related metabolites. There was some recovery after cooler weather during the final two days of the experiment. The degree of change was greater in muddy versus sandy sediments. Our findings provide new evidence of the metabolomic response of these important bivalve to heat stress, which could be used for resource managers when implementing strategies to mitigate the impacts of climate change on valuable marine resources.
Journal Article
Cool experiments with heat and cold
Reading about heat and cold is just the tip of the iceberg. This book lets readers create their own icebergs! Hands-on activities make learning about heat and cold both tangible and fun. Simple explanations help readers grasp complex concepts while step-by-step instructions and accompanying photographs ensure they will master each experiment.
Book
Evaluation of a Long-Term Thermal Load on the Sealing Characteristics of Potential Sediments for a Deep Radioactive Waste Disposal
An in situ and a batch heating experiment were applied on the fine-grained sediments of the Opalinus Clay from Mont Terri (Switzerland) and the Boom Clay of Mol (Belgium), both being currently studied as potential host formations for deep nuclear waste disposal. The purpose was here to test the impact of a 100 °C temperature rise that is expected to be produced by nuclear waste in deep repositories. The experiment on the Opalinus Clay mimicked real conditions with 8-months operating heating devices stored in core drillings into the rock. The comparison of the major, trace, rare-earth elemental contents and of the whole-rock K-Ar data before and after heating shows only a few variations beyond analytical uncertainty. However, the necessary drillings for collecting control samples after the experiment added an unexpected uncertainty to the analyses due to the natural heterogeneity of the rock formation, even if very limited. To overcome this aspect, Boom Clay ground material was subjected to a batch experiment in sealed containers during several years. The drawback being here the fact that controls were limited with, however, similar reproducible results that also suggest limited elemental transfers from rock size into that of the <2 μm material, unless the whole rocks lost more elements than the fine fractions. The analyses generated by the two experiments point to identical conclusions: a visible degassing and dewatering of the minerals that did not induce a visible alteration/degradation of the host-rock safety characteristics after the short-term temperature increase.
Journal Article
How hot is hot? : science projects with temperature
Provides instructions for doing experiments involving temperature using items found around the house.
Book
Emergence of Non-Fourier Hierarchies
The non-Fourier heat conduction phenomenon on room temperature is analyzed from various aspects. The first one shows its experimental side, in what form it occurs, and how we treated it. It is demonstrated that the Guyer-Krumhansl equation can be the next appropriate extension of Fourier’s law for room-temperature phenomena in modeling of heterogeneous materials. The second approach provides an interpretation of generalized heat conduction equations using a simple thermo-mechanical background. Here, Fourier heat conduction is coupled to elasticity via thermal expansion, resulting in a particular generalized heat equation for the temperature field. Both aforementioned approaches show the size dependency of non-Fourier heat conduction. Finally, a third approach is presented, called pseudo-temperature modeling. It is shown that non-Fourier temperature history can be produced by mixing different solutions of Fourier’s law. That kind of explanation indicates the interpretation of underlying heat conduction mechanics behind non-Fourier phenomena.
Journal Article