Experimental Measurement of Direct Thermal Radiation Through Single-Layer Square-Cell Plain Woven Screens

2015 ◽  
Vol 138 (1) ◽  
Author(s):  
Javad Hashempour ◽  
Ahmad Sharifian ◽  
John Billingsley
Keyword(s):  
Single Layer ◽  
Radiant Heat ◽  
Radiant Heat Flux ◽  
Severe Damage ◽  
Direct Radiation ◽  
Tunnel Vision ◽  
Four Square ◽  
Square Cell

Australian bushfires have repeatedly killed many people and caused severe damage. Previous studies have identified direct flame contact and radiant heat as the main cause of fatalities. The role of screens to limit the radiation exposure of an object by a fire on the opposite side of the screen is well-known, but still it has not been experimentally quantified. A screen between a radiation source and an object divides the radiant heat flux (RHF) into two parts. The first part is the direct RHF (DRHF) that passes directly through the screen without any interaction. The second part is indirect RHF (IRHF), which includes both emitted and reflected RHFs by the heated screen. This experimental study deals with the DRHF, which is dependent on the screen porosity and is independent of the material composition or the surface quality of the screen. The experimental results of four square-cell, plain woven screens, with porosities ranging from 41% to 66%, show that the passing ratios (PRs) of DRHF through screens are less than those suggested by their porosity. Four empirical equations have been developed to determine the PR of the direct radiation through screen and the tunnel vision angles of the screens.

scholarly journals HEAT DAMAGE AND DRYING EFFECTS ON SEED QUALITY

1985 ◽  
Vol 2 ◽  
pp. 53-57
Author(s):  
M.J. Hill ◽  
C.R. Johnstone
Keyword(s):  
Seed Quality ◽  
Seed Mass ◽  
Radiant Heat ◽  
Thermophilic Fungi ◽  
Seed Moisture Content ◽  
Heat Damage ◽  
Heated Air ◽  
Seed Moisture

Heat damage to seed can occur as a result of the cumulative effects of respiration and fungal heating, and by the accumulation and retention of radiant heat within the seed mass following harvest - both situations being collectively referred to as 'field heating'. Another type of heating damage occurs in heated air drying systems. Excessive drying air temperature can have deleterious effects on seed quality - this is generally referred to as "drying damage". Both 'field heating' and 'drying damage' result in loss of quality due to the thermosensitivity of seeds. This is a characteristic which is markedly influenced by the seed moisture content, by the extent and duration of heat production, and by the retention of heat within the seed mass. The role of the thermophilic fungi, Aspergillus spp., in accentuating heat damage, and the effects of both 'field heat' and 'drying damage' on the market acceptability and quality of seed is also discussed. Keywords: Respiration heating, fungal heating, Aspergillus, seed quality

scholarly journals Characterizing the Tensile Strength of the Fabrics Used in Firefighters’ Bunker Gear under Radiant Heat Exposure

Polymers ◽  
2022 ◽  
Vol 14 (2) ◽  
pp. 296
Author(s):  
Nur-Us-Shafa Mazumder ◽  
Sumit Mandal ◽  
Robert J. Agnew ◽  
Adriana Petrova ◽  
Lynn M. Boorady ◽  
...  
Keyword(s):  
Heat Flux ◽  
Tensile Strength ◽  
National Fire Protection Association ◽  
Single Layer ◽  
Radiant Heat ◽  
Radiant Heat Flux ◽  
Thermal Hazards ◽  
Fabric System ◽  
Four Levels ◽  
The Impact

More than 60,000 firefighters’ injuries were reported by the National Fire Protection Association in the U.S. in 2019. Inadequate protection by bunker gear could be a reason for most of the injuries. Firefighters repeatedly encounter thermal hazards due to their job responsibilities. Degradation could occur on bunker gear fabric during thermal exposure. It has been found that the presence of moisture affects performance as well, which may come from wearers’ sweat. Proper evaluation of the tensile strength of the fabrics used in bunker gear could provide information essential for maintenance the overall integrity of the gear. An evaluation of the tensile strength of fabrics when exposed to 10, 15, and 20 kW/m2 radiant heat flux in the presence of moisture is reported. In each fabric system, a total of sixty-four different samples were prepared for four different types of fabric and four levels of moisture which were exposed to three different radiant heat flux for five minutes. Heat flux and moisture levels have significant impact on tensile strength. The effect of moisture on tensile strength in a three-layered fabric system is higher than that for a single layer fabric. An understanding of the impact of heat and moisture on fabric strength has been achieved.

scholarly journals IMPACT OF EXTERNAL FACTORS ON HEALTH AND WORKING ENVIRONMENT

2020 ◽  
Vol 15 (1) ◽  
pp. 24-27
Author(s):  
Miriam Jankalová
Keyword(s):  
Well Being ◽  
Radiant Heat ◽  
External Factors ◽  
Working Environment ◽  
Safe Working

Employees are affected by various factors of the working environment. Examples are noise, lighting, microclimate (temperature, airflow and humidity, dustiness, radiant heat). However, these are not the only indicators indicating the quality of the working environment in today's busy times. High workloads with low appreciation, bad atmosphere, ambiguously defined goals and powers accumulate until they gradually transform into a state of complete exhaustion, apathy, dislike, disinterest in society and people. And it is the role of employers to create conditions that ensure employees work in healthy and safe working environment while maintaining the principles of mental, physical and social well-being.

Cognitive Health Counseling 40+

2013 ◽  
Vol 21 (1) ◽  
pp. 24-33 ◽  
Author(s):  
Anne Eschen ◽  
Franzisca Zehnder ◽  
Mike Martin
Keyword(s):  
Outcome Variable ◽  
Pilot Phase ◽  
Subjective Memory ◽  
Cognitive Health ◽  
Health Counseling ◽  
Agents Of Change ◽  
Main Outcome Variable ◽  
Further Development

This article introduces Cognitive Health Counseling 40+ (CH.CO40+), an individualized intervention that is conceptually based on the orchestration model of quality-of-life management ( Martin & Kliegel, 2010 ) and aims at improving satisfaction with cognitive health in adults aged 40 years and older. We describe the theoretically deduced characteristics of CH.CO40+, its target group, its multifactorial nature, its individualization, the application of subjective and objective measures, the role of participants as agents of change, and the rationale for choosing participants’ satisfaction with their cognitive health as main outcome variable. A pilot phase with 15 middle-aged and six older adults suggests that CH.CO40+ attracts, and may be particularly suitable for, subjective memory complainers. Implications of the pilot data for the further development of the intervention are discussed.

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