Estimation of Air Temperature Induced by a Heat Source in a Compartment with Displacement Ventilation

The subject of the research was an air-water heat pump, model PCUW 2.5kW from HEWALEX, installed in a single-family house. The pump is only used for heating water. The research was carried out from 25-08-2017 to 18-09-2017 in the village of Zborowice, in Malopolska region, Poland. The data were recorded from the heat pump system: temperature of the lower heat source (external air), temperature of the upper heat source (water temperature in the tank), time of heat pump was calculated during the analysed cycle of work and electrical energy consumption. The Coefficient Of Performance (COP) of the analysed air-water heat pump was determined. The analysis of the results was carried out using the MATLAB and EXCEL statistical tools. The correlation between COP coefficient and external air temperature is strong: 0.67.

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A four-year record of the meteorological parameters, radiative and turbulent energy fluxes at the edge of the East Antarctic Ice Sheet, close to Schirmacher Oasis

Antarctic Science ◽

10.1017/s095410201300028x ◽

2013 ◽

Vol 26 (1) ◽

pp. 93-103 ◽

Cited By ~ 2

Author(s):

H.S. Gusain ◽

V.D. Mishra ◽

M.K. Arora

Keyword(s):

Heat Flux ◽

Heat Source ◽

Air Temperature ◽

Meteorological Parameters ◽

Ice Sheet ◽

Turbulent Energy ◽

Energy Fluxes ◽

Glacier Surface ◽

Katabatic Winds ◽

Schirmacher Oasis

AbstractSurface energy fluxes of the ice sheet close to oases (ice-free land regions) are crucial in the case of retreating ice sheet and growing oasis areas. This study presents a four-year record of the meteorological parameters, radiative and turbulent energy fluxes at the edge of the Antarctic ice sheet, close to Schirmacher Oasis in Dronning Maud Land, East Antarctica from March 2007–February 2011. The energy fluxes were analysed for summer season, winter season and transition periods. High katabatic winds were observed during winter (seasonal mean 9.3 m s-1) as compared to other seasons. A high correlation (r2 = 0.89) was observed between the glacier surface temperature and air temperature, and regression relations were obtained for summer, winter and transition periods. The net radiative flux was the main heat source to the glacier during summer (46.8 W m-2) and heat sink during winter (-42.2 W m-2). Sensible heat flux (annual mean 32 W m-2) was the heat source and latent heat flux (annual mean -61 W m-2) was the heat sink to the glacier surface, averaged over all seasons. Comparison with other coastal or dry valley locations in Antarctica show that low humidity (50%), high katabatic winds (8.3 m s-1) and mild surface (-11.4°C) and air temperature (-10.2°C) contribute to high latent heat flux at the present study location.

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Snow Utilization as Cold Heat Source - Advantages and Features

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.889.549 ◽

2019 ◽

Vol 889 ◽

pp. 549-556

Author(s):

Seiji Kamimura ◽

Yoshiomi Ito

Keyword(s):

Heat Source ◽

Heat Pump ◽

Air Temperature ◽

Temperature Control ◽

Annual Cost ◽

Air Conditioning ◽

Cost Effective ◽

Shiitake Mushroom ◽

Pump Unit ◽

Heat Pump Unit

In the summer of 2014, the air-conditioning performance of four different snow-utilizing facilities in Niigata and Nagano Prefectures in Japan were evaluated. Systems with a snow storeroom, a rice depot and spa resort, showed the advantages of stable and flexible air temperature control with high deodorizing and dedusting effects. The investment will be earned back in less than 10 years. The system with a snow mound, shiitake mushroom greenhouses, showed that the annual cost is cheaper than that of the heat pump unit. A highway lavatory with daily snow delivery was not cost effective.

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Simulation of Air Temperature in an Under-Bridge Storehouse

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.178-181.2557 ◽

2012 ◽

Vol 178-181 ◽

pp. 2557-2560

Author(s):

Han Xiao ◽

Yong Ding ◽

Xin Tang Wang

Keyword(s):

Heat Source ◽

Turbulence Model ◽

Air Temperature ◽

Volumetric Heat Source ◽

Simple Geometry

In this paper, one certain space under bridge which was used as a storehouse has been simulated numerically. The flow was considered turbulent and buoyant. A simple geometry was adopted, consisting of a room with a door that plays the role of inlet and another of outlet for the air. Four bundles of wood burners which considered as a volumetric heat source were placed evenly in the space. The problem was simulated by using the RNG K-ε turbulence model, modified to account for buoyancy effects. Several useful results were obtained.

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Dynamic design model of displacement ventilation

E3S Web of Conferences ◽

10.1051/e3sconf/201911104049 ◽

2019 ◽

Vol 111 ◽

pp. 04049

Author(s):

Natalia Lastovets ◽

Risto Kosonen ◽

Juha Jokisalo ◽

Simo Kilpeläinen

Keyword(s):

Temperature Gradient ◽

Air Temperature ◽

Simulation Software ◽

Building Simulation ◽

Temperature Stratification ◽

Thermal Mass ◽

Displacement Ventilation ◽

Lecture Room ◽

Accurate Temperature ◽

Gradient Calculation

An accurate temperature gradient calculation is essential for displacement ventilation (DV) system design, since it directly relates to the calculation of the required supply air flow rate. Inaccurate temperature prediction can cause the poor thermal comfort and w sizing of the ventilation and cooling systems. Several simplified nodal models were developed and implemented in the various building simulation software to estimate the temperature stratification in rooms with DV. Recent studies reveal that the multi-nodal models provide the most accurate temperature gradient prediction. However, the most building simulation software uses the air models with only one air node. The present study introduces the dynamic temperature gradient model for DV and investigates the effect of thermal mass on the temperature stratification. The model was validated with the experimental results of the lecture room with displacement ventilation. The room air temperature measurements were conducted during three weeks at 20 different heights. The supply air temperature and occupancy rate were recorded during each scheduled lecture. The developed dynamic nodal model is able to accurately calculate the air temperatures in occupied zone. The effect of the thermal mass and varied heat loads on the indoor air temperature stratification is analysed for the lecture room with DV.

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