Energy and Environmental Analysis of a Solar Evacuated Tube Heat Pipe Integrated Thermoelectric Generator Using IoT

This paper investigates the solar evacuated tube heat pipe system (SEHP) coupled with a thermoelectric generator (TEG) using the internet of things (IoT). The TEGs convert heat energy into electricity through the Seebeck effect that finds application in the waste heat recovery process for the generation of power. The present work deals with the theoretical study on solar evacuated tube heat pipe integrated TEG and it is validated experimentally using with and without parabolic trough concentrating collector. And the carbon credit of the TEG system is determined to find its potential in the environmental aspect. Also, the boost type converter is used to raise the power output by increasing the voltage from the TEG for rural electrifications. However, it is found that the maximum power output due to the influence of the parabolic trough concentrator results in increased efficiency when compared with the non-concentrating SEHP-TEG system. The TEG output power can be boosted up to a maximum of 5.98 V using a power electronic boost converter. Besides, the recorded real sensor data with Arduino is implemented in the experimental process for automatic remote monitoring of the temperature.

Investigation of Thermal Performance of Evacuated Tube with Parabolic Trough Collector with and without Porous Media

In this paper a new model has demonstrated that it operates in a moderate performance scale to generate hot water. In its early stage, the preliminary model, which built with double pass water tube inside evacuated tube, was investigated experimentally. The model was tested inside room under different operation conditions in terms of solar radiation 300, 400, 500 and 600 W/m2 and water mass flow rates 0.00305 and 0.0083kg/s. In the first case, there was a problem because of the air gap inside the tube and surrounding the double pass water tube, so In the second stage, two different filling medium inside the evacuated tube was proposed to modify the preliminary model. The mediums cases include porous media (stainless steel wire mesh and Aluminum fiber metallic). The results show that maximum efficiency without porous media was 62.4% at 0.0083 kg/s and heat flux 600 W/m2, but after porous media applied, the efficiency reached 79.4% at 99.997% porosity of Aluminum fiber metallic and heat flux 600 W/m2 with same water mass flow.

Comparison of the effects of open-tube and evacuated tube–assisted sampling methods on thromboelastography variables for blood samples from healthy dogs

OBJECTIVE To compare the effects of open-tube blood sampling with previously investigated blood sampling methods via evacuated tube on thromboelastography variables for blood samples from dogs. ANIMALS 10 healthy Beagles from the research colony owned by the Clinic of Small Animal Internal Medicine, University Veterinary of Medicine, Vienna, were used. PROCEDURES In this prospective study, blood was sampled from each dog serially into citrate solution–containing tubes via 20-gauge needle. One evacuated tube was filled from a jugular vein via the evacuated tube port, and the second tube was opened and filled by catching blood flowing through the needle from a lateral saphenous vein. Venipuncture quality was scored with a previously described method. Thromboelastography was performed for each sample. RESULTS Inferential statistics used with the Wilcoxon signed rank test showed significant differences in reaction time (R) of 3.43 ± 0.84 minutes versus 4.53 ± 0.62 minutes (mean ± SD) between evacuated tube assisted and open-tube sampling, respectively. No other significant differences were identified. CLINICAL RELEVANCE The sampling methods compared have a small but significant effect on R in thromboelastographic analysis for blood samples from healthy dogs. Shear stress by vacuum sampling seems to accelerate coagulation in jugular blood samples harvested by evacuated tube, resulting in a shortened R. Results suggested that the open-tube method avoids shear stress induced activation of coagulation and is an appropriate sampling method for thromboelastography when used within a standardized protocol.