Numerical model of heat exchange between a worker body and the hot environment

• Autorzy: Wacławik J.

Warianty tytułu

PL

Numeryczne modelowanie wymiany ciepła między ciałem pracownika i otoczeniem gorącym

• Języki publikacji: EN

Abstrakty

EN

The subject of considerations enclosed in this paper is the mathematical model of the worker's body-environment heat exchange in mining working. At the low and moderate temperature and humidity of air the basic way of carrying away of heat from human body is convection. In the difficult climatic conditions the evaporation of sweat is of prevailing importance. Heat exchange between miner's body and his environment was calculated for transient state, when the temperature of body is changing. It has been assumed that the average skin temperature is a factor controlling convective, radiant and evaporative modes of heat exchange. The state of thermal stress is determined by accumulation of heat in worker's body and increase of core and rectal temperature. The second measure of thermal stress is maximum of sweat rates emitted during work and dehydration level. The heat balance of human body affords possibilities for estimation of these parameters.

PL

Przedmiotem pracy są zagadnienia standardów komfortu cieplnego pracownika, określone na podstawie bilansu cieplnego jego organizmu. Przy niskiej i umiarkowanej temperaturze i wilgotności powietrza oraz przy małym wydatku energetycznym ciepło z ciała pracownika odprowadzane jest do otoczenia przede wszystkim drogą konwekcji. W trudnych warunkach klimatycznych oraz przy wydatku energetycznym odpowiadającym pracy umiarkowanej lub ciężkiej dominującą rolę odgrywa parowanie potu. Stan obciążenia termicznego może być modelowany numerycznie metodami bilansu cieplnego ciała pracownika, sporządzanego dla nieustalonej wymiany ciepła z otoczeniem. Stan obciążenia (stresu) i napięcia cieplnego może być oceniany na podstawie akumulacji ciepła w ciele człowieka i wzrostu temperatury wewnętrznej ciała lub temperatury w rectum oraz maksymalnej ilość potu wydzielanej podczas pracy i stopnia odwodnienia organizmu.

Słowa kluczowe

EN

thermal comfort; heat stress; thermoregulation model

PL

warunki pracy cieplne; napięcie cieplne; termoregulacja

• Wydawca: Instytut Mechaniki Górotworu PAN
• Czasopismo: Archives of Mining Sciences
• Rocznik: 2010
• Tom: Vol. 55, no 3
• Strony: 573--588
• Opis fizyczny: Bibliogr. 29 poz., tab.

Twórcy

autor

Wacławik J.

• AGH University of Science and Technology, Faculty of Mining and Geoengineering, Al. Mickiewicza 30, 30-059 Kraków, Poland

Bibliografia

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