Numerical Investigation of Thermal Characteristics in a Solar Chimney Project

2013 ◽  
Vol 136 (1) ◽  
Author(s):  
Hongtao Xu ◽  
Fariborz Karimi ◽  
Mo Yang
Keyword(s):  
Temperature Field ◽  
Numerical Investigation ◽  
Thermal Characteristics ◽  
Soil Surface ◽  
Solar Chimney ◽  
Simulation Methodology ◽  
Plant Cultivation ◽  
Soil Surface Temperature ◽  
Lower Temperature ◽  
Heat Amount

In order to create interior multiclimate zones suitable for plant cultivation in a solar chimney project proposed for the World Horticultural Exposition 2016 in China, the numerical investigation is performed to a solar chimney with 2 km radius and 1 km height. The simulation methodology is validated by experimental data. The impacts of inlet height and radius to interior thermal characteristics are evaluated. It is found that the temperature field is much similar when the inlet height decreases from 3.8 m to 0.5 m. With further decrease of the inlet height to 0.2 m, its impact to temperature field is significant. The temperature field is similar though the radius of solar chimney decreases from 2.0 km to 1.725 km. Further decrease to 1.13 km results in much lower temperature field as less radiate heat is obtained. The procedure of soil surface temperature calculation is also proposed to obtain the supplementary heat amount maintaining the required temperature for plant cultivation.

Using soil surface temperature to assess soil evaporation in a drip irrigated vineyard

2013 ◽  
Vol 116 ◽  
pp. 128-141 ◽  
Author(s):  
B.L. Kerridge ◽  
J.W. Hornbuckle ◽  
E.W. Christen ◽  
R.D. Faulkner
Keyword(s):  
Surface Temperature ◽  
Soil Surface ◽  
Soil Evaporation ◽  
Soil Surface Temperature

Analytical Model to Predict Nonhomogeneous Soil Temperature Variation

1995 ◽  
Vol 117 (2) ◽  
pp. 100-107 ◽  
Author(s):  
M. Krarti ◽  
D. E. Claridge ◽  
J. F. Kreider
Keyword(s):  
Thermal Properties ◽  
Soil Temperature ◽  
Temperature Variation ◽  
Analytical Model ◽  
Soil Surface ◽  
Deep Soil ◽  
Soil Thermal Properties ◽  
Order Of Magnitude ◽  
Soil Surface Temperature ◽  
Annual Time

This paper presents an analytical model to predict the temperature variation within a multilayered soil. The soil surface temperature is assumed to have a sinusoidal time variation for both daily and annual time scales. The soil thermal properties in each layer are assumed to be uniform. The model is applied to two-layered, three-layered, and to nonhomogeneous soils. In case of two-layered soil, a detailed analysis of the thermal behavior of each layer is presented. It was found that as long as the order of magnitude of the thermal diffusivity of soil surface does not exceed three times that of deep soil; the soil temperature variation with depth can be predicted accurately by a simplified model that assumes that the soil has constant thermal properties.

Numerical Investigation on Leading Edge of Film Cooling Blade with Different Turbulence and Blowing Ratios

2014 ◽  
Vol 1070-1072 ◽  
pp. 1731-1734
Author(s):  
Shao Hua Li ◽  
Ge Wu ◽  
Ling Zhang
Keyword(s):  
Temperature Field ◽  
Numerical Investigation ◽  
Turbulence Intensity ◽  
Film Cooling ◽  
Leading Edge ◽  
Cooling Efficiency ◽  
Simulated Temperature

In order to investigate the influence of cooling efficiency of leading edge of film cooling blade with different turbulence intensity and blowing ratios,which use method of N-S equation,various blowing ratios of 1.0、1.5 and 2.0,various turbulence intensity of 5%、12%、20% and 30%,it simulated temperature field in leading edge of film cooling blade.The results show: cooling efficiency decreased when blowing ratios is increased.When turbulence intensity is 5%、12% and 20%,it obtains maximum cooling efficiency blowing ratios of 1.0.When turbulence intensity is 30%,it obtains maximum cooling efficiency blowing ratios of 1.5. In blowing ratios of 1.0,cooling efficiency decreased when turbulence increased.But in blowing ratios of 1.5 and 2.0,cooling efficiency increased when turbulence increased.

scholarly journals RESEARCH AND EVALUATION OF KART NOISE SPREAD INTO THE LIVING ENVIRONMENT / GOKARTŲ KELIAMO TRIUKŠMO SKLAIDOS Į GYVENAMĄJĄ APLINKĄ TYRIMAI IR VERTINIMAS

2014 ◽  
Vol 6 (4) ◽  
pp. 356-361
Author(s):  
Giedrius Juozaponis ◽  
Raimondas Grubliauskas
Keyword(s):  
Wind Speed ◽  
Experimental Studies ◽  
Soil Surface ◽  
Sound Level ◽  
Living Environment ◽  
Noise Levels ◽  
Noise Propagation ◽  
Soil Surface Temperature ◽  
Service Data ◽  
Living Area

The paper examines kart noise propagation in the living environment and sought measures for suppressing it. To conduct experimental studies, precision sound level analyzer Bruel & Kjaer 2260th has been used. In cooperation with the Lithuanian Hydrometeorological Service, data on relative humidity, wind speed and direction, soil surface temperature and air temperature have been applied. According to the Lithuanian Hygiene Standard HN 33:2011 Noise Thresholds in Residential and Public Buildings and Their Environment, the areas with an elevated noise level are identified thus selecting noise reduction measures aimed at reducing noise levels up to the permitted ones. The analysis of the obtained results has focused on the regularities between noise propagation and meteorological events and their impact on the spread of noise. The environmental factors more or less influencing the climate and noise spread in the living area have been determined. With reference to the received information, the ways to reduce noise have been suggested. Straipsnyje nagrinėjamas gokartų keliamo triukšmo sklidimas į gyvenamąją aplinką ir ieškoma priemonių jam slopinti. Eksperimentiniams tyrimams atlikti buvo naudojamas precizinis garso lygio analizatorius „Bruel&Kjaer 2260“. Bendradarbiaujant su Lietuvos hidrometeorologijos tarnyba panaudoti santykinės oro drėgmės, vėjo stiprumo ir krypties, dirvožemio paviršiaus temperatūros bei oro temperatūros duomenys. Vadovaujantis Lietuvos higienos normomis HN 33:2011 „Triukšmo ribiniai dydžiai gyvenamuosiuose ir visuomeninės paskirties pastatuose bei jų aplinkoje“ nustatomos zonos, kuriose triukšmo lygis yra viršijamas, ir parenkant triukšmo mažinimo priemones siekiama triukšmą sumažinti iki leidžiamųjų normų. Gautų rezultatų analizės metu ieškoma dėsningumų tarp triukšmo sklidimo ir meteorologinių reiškinių bei jų daroma įtaka triukšmo plitimui. Nustatomi aplinkos klimato veiksniai, darantys įtaką ar mažiau veikiantys triukšmo sklaidą gyvenamojoje teritorijoje. Atsižvelgiant į gautus rezultatus siūlomi triukšmo mažinimo būdai.

Ferrofluid Convection in a Lid-Driven Cavity

2018 ◽  
Vol 388 ◽  
pp. 407-419
Author(s):  
Fatih Selimefendigil ◽  
Ali Jawad Chamkha
Keyword(s):  
Heat Transfer ◽  
Magnetic Dipole ◽  
Richardson Number ◽  
Vertical Wall ◽  
Thermal Characteristics ◽  
Dipole Source ◽  
Dipole Strength ◽  
Square Enclosure ◽  
Lower Temperature ◽  
The Right

This study numerically investigates the mixed convection of ferrofluids in a partially heated lid driven square enclosure. The heater is located to the left vertical wall and the right vertical wall is kept at constant lower temperature while other walls of the cavity are assumed to be adiabatic. The governing equations are solved with Galerkin weighted residual finite element method. The influence of the Richardson number (between 0.01 and 100), heater location (between 0.25 H and 0.75H), strength of the magnetic dipole (between 0 and 4), and horizontal location of the magnetic dipole source (between-2H and-0.5H) on the fluid flow and heat transfer are numerically investigated. It is found that local and averaged heat transfer deteriorates with increasing values of Richardson number and magnetic dipole strength. The flow field and thermal characteristics are sensitive to the magnetic dipole source strength and its position and heater location.

scholarly journals Determination of the united quality latent index of adaptability (UQLIA) and contribution of some environmental parameters to it for Deschampsia antarctica populations, Galindez island (Maritime Antarctic) season 2017/2018

2019 ◽  
Vol 16 (2) ◽  
pp. 190-202
Author(s):  
I. Y. Parnikoza ◽  
N. Y. Miryuta ◽  
V. Y. Ivanets ◽  
E. O. Dykyi
Keyword(s):  
Surface Temperature ◽  
Pairwise Comparison ◽  
Environmental Parameters ◽  
Soil Surface ◽  
Deschampsia Antarctica ◽  
Near Surface ◽  
Soil Surface Temperature ◽  
Experimental Populations ◽  
The Individual

The purpose of our work has been to determine the indicator of complex adaptability — the United Quality Latent Index of Adaptability (UQLIA) for the experimental populations of Deschampsia antarctica É. Desv. and study the contribution to it of some environmental factors such as the near soil surface temperature and organogens content. Materials and methods. The determination of UQLIA was based on a pairwise comparison of the differences between investigated parameters of populations by mathematical regression techniques. The soil surface temperature was measured by loggers installed near plants in each locus during April 2017 – April 2018. Results and conclusions. Temperature fluctuations were described during December 2017 – February 2018 for twelve experimental populations of D. antarctica and one control fragment of moss turf subformation from Galindez Island. Significant variations in average daily near surface temperature were observed during the study period between populations, especially in December and January. The UQLIA of D. antarctica for this season was calculated on the basis of the projective cover, biometric indices of generative plants and the content of protective and reserve proteins in seeds for the eleven populations. The values of the United Soil Surface Temperature Influence Index (UTII) for the season summer months and the United Organogens Content in Soil Influence Index (UOCSII) have been calculated for the individual parameters of D. antarctica plants adaptability. The reliable contribution of UTII to ULIA has been shown for December and January, at the moment of the greatest variation of soil surface temperature. UOCSII provided a reliable contribution to the ULIA only in the amount of UTII. Keywords: Deschampsia antarctica, United Quality Latent Index of Adaptability (UQLIA), contribution of soil surface temperature and organogens content to complex adaptability.

scholarly journals Two-Dimensional Spectral Analysis of Soil Surface Temperature

Hilgardia ◽  
1988 ◽  
Vol 56 (3) ◽  
pp. 1-28 ◽  
Author(s):  
M. Bazza ◽  
R. H. Shumway ◽  
D. R. Nielsen
Keyword(s):  
Spectral Analysis ◽  
Surface Temperature ◽  
Soil Surface ◽  
Two Dimensional ◽  
Soil Surface Temperature

Thermal Deformation Analysis for the Guideway of Large-Type CNC Lathe Based on Finite Element Method

2011 ◽  
Vol 58-60 ◽  
pp. 198-204
Author(s):  
Feng Shou Zhang ◽  
Don Gyan Wang ◽  
Jian Ting Liu ◽  
Feng Kui Cui
Keyword(s):  
Finite Element ◽  
Temperature Field ◽  
Thermal Deformation ◽  
Thermal Characteristics ◽  
Thermal Error ◽  
Deformation Analysis ◽  
Element Analysis ◽  
Large Type ◽  
Cnc Lathe ◽  
Optimizing Design

Friction between the guideway and the bench of large-type CNC lathe will cause thermal deformation of the guideway, which causes processing error of the lathe，thereby reduces machining precision of the workpiece. The authors establish the mathematical model of temperature field and thermal deformation of the guideway in the work process, numerically simulate the guideway thermal characteristics by ANSYS finite element analysis software, and obtain the distribution regularities of temperature field and thermal deformation and their major influencing factors, which provide a theoretical basis for optimizing design and thermal error compensation design of the lathe guideway.

Edaphic respiration in bell pepper cultivation under biological fertilizers, doses and application times

2020 ◽  
pp. 434
Author(s):  
Ygor Henrique Leal
Keyword(s):  
Soil Moisture ◽  
Experimental Design ◽  
Soil Surface ◽  
Bell Pepper ◽  
The Other ◽  
Sheep Manure ◽  
Soil Surface Temperature ◽  
Night And Day ◽  
Absolute Control ◽  
Organic Compost

Biological fertilizers promote several benefits to the soil, and one of the ways to evaluate their quality is to determine the edaphic respiration. The present study aimed to evaluate edaphic respiration in bell pepper cultivation under doses and times of application of biological fertilizers. Two experiments were performed with applications of biological fertilizers prepared from manure and enriched organic compost, one using bovine manure (BM) and the other, sheep manure (SM). The experimental design used was in randomized blocks, in a 4 x 3 + 1 factorial scheme, with three replications, referring to the doses of biological fertilizers (100, 200, 300 and 400 dm³ ha-1), application times (0, 30 and 60 days after transplanting – DAT) and the absolute control. The following variables were evaluated during the night and day: soil surface temperature (Tsurf) and 10 cm deep (T10), soil moisture (M) and edaphic respiration (ER). SM provided the highest ER in the two shifts evaluated. The use of 400 and 300 dm³ ha-1 of SM, at times of 0 and 30 DAT, respectively, provided greater edaphic respiration in relation to the absence of manure during the day.

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