Ongoing Research

Thermetrics equipment is utilized around the world.  Here are research papers from 2015 and 2016.  Please contact us if you want to add your research abstract to this list.

 

Opportunities and constraints of presently used thermal manikins for thermo-physiological simulation of the human body

International Journal of Biometeorology

March 2016, Volume 60, Issue 3, pp 435–446

First online: 29 July 2015

Agnes Psikuta , Kalev Kuklane, Anna Bogdan, George Havenith, Simon Annaheim, René M. Rossi

http://link.springer.com/article/10.1007%2Fs00484-015-1041-7

 Abstract -- Combining the strengths of an advanced mathematical model of human physiology and a thermal manikin is a new paradigm for simulating thermal behaviour of humans. However, the forerunners of such adaptive manikins showed some substantial limitations. This project aimed to determine the opportunities and constraints of the existing thermal manikins when dynamically controlled by a mathematical model of human thermal physiology. Four thermal manikins were selected and evaluated for their heat flux measurement uncertainty including lateral heat flows between manikin body parts and the response of each sector to the frequent change of the set-point temperature typical when using a physiological model for control. In general, all evaluated manikins are suitable for coupling with a physiological model with some recommendations for further improvement of manikin dynamic performance. The proposed methodology is useful to improve the performance of the adaptive manikins and help to provide a reliable and versatile tool for the broad research and development domain of clothing, automotive and building engineering.


Correlation of bench scale and manikin testing of fire protective clothing with thermal shrinkage effect considered

Fibers and Polymers

June 2015, Volume 16, Issue 6, pp 1370-1377

First online: 11 July 2015

Min Wang, Xiaohui Li, Jun Li

http://link.springer.com/article/10.1007/s12221-015-1370-5

Abstract -- Bench scale test and flame manikin test are two typical methods to evaluate the thermal protection provided by flame resistant fabrics or clothing. In this paper, the correlation between the test results of the two protocols was investigated. A group of fabrics commonly used in fire protective clothing were evaluated by a thermal protective performance (TPP) tester. Conditions with or without an air spacer were applied. Protective performance of the garments made of these fabrics with identical design feature was evaluated by a flame manikin testing system. Portable 3D body scanning technique was firstly used to characterize the air gap size change between the garment and manikin after flash fire exposure. The results showed that there was no significant correlation between the bench scale test and flame manikin test results in terms of TPP value and percent body burn. Thermal shrinkage which was not included in the bench scale test was demonstrated to be a key factor contributing to the weak correlation. It significantly decreased the air gap size between the garment and manikin and greatly affected the heat transfer after the flash fire exposure had ceased in the manikin test. Besides the TPP value, thermal shrinkage was suggested to be considered in the bench scale test as a parameter to predict the thermal protective property of flame resistant fabrics when made into garments.

 


 

Effect of two sweating simulation methods on clothing evaporative resistance in a so-called isothermal condition

International Journal of Biometeorology

July 2016, Volume 60, Issue 7, pp 1041–1049

First online: 05 November 2015

Yehu Lu, Faming Wang , Hui Peng

http://link.springer.com/article/10.1007/s00484-015-1095-6

Abstract -- The effect of sweating simulation methods on clothing evaporative resistance was investigated in a so-called isothermal condition (Tmanikin= Ta = Tr). Two sweating simulation methods, namely, the pre-wetted fabric “skin” (PW) and the water supplied sweating (WS), were applied to determine clothing evaporative resistance on a “Newton” thermal manikin. Results indicated that the clothing evaporative resistance determined by the WS method was significantly lower than that measured by the PW method. In addition, the evaporative resistances measured by the two methods were correlated and exhibited a linear relationship. Validation experiments demonstrated that the empirical regression equation showed highly acceptable estimations. The study contributes to improving the accuracy of measurements of clothing evaporative resistance by means of a sweating manikin.

 


 

Effects of moisture content and clothing fit on clothing apparent ‘wet’ thermal insulation: A thermal manikin study 

Faming Wang1,2

Wen Shi1

Yehu Lu1

Guowen Song3

Rene Michel Rossi4

Simon Anaheim4

http://trj.sagepub.com/content/early/2015/04/17/0040517515580527.abstract

Abstract --  ‘Wet’ thermal insulation, defined as the thermal insulation when clothing gets partially or fully wet, is an important physical parameter to quantify clothing thermal comfort. As the water/sweat gradually occupies the intra-yarn and inter-yarn air voids of the clothing material, the clothing intrinsic thermal insulation will be diminished and, hence, contribute to the loss of total insulation. In cold conditions, a loss in total thermal insulation caused by sweating may result in an inadequate thermal insulation to keep thermal balance and eventually leads to the development of hypothermia and cold injuries. Therefore, it is imperative to investigate the effect of clothing fit and moisture content on clothing ‘wet’ insulation. In this study, the ‘wet’ thermal insulation of three two-layer clothing ensembles was determined using a Newton thermal manikin. Four levels of moisture content were added to the underwear: 100, 200, 500 and 700 g. The clothing apparent ‘wet’ thermal insulation under different testing scenarios was calculated and compared. A third-degree polynomial relationship between the reduction in ‘wet’ thermal insulation and the moisture content added to underwear was obtained. Further, it was evident that the clothing fit has a minimal effect on the apparent ‘wet’ thermal insulation. The findings may have important applications in designing and engineering functional cold weather clothing and immersion suits.


Total heat loss as a predictor of physiological response in wildland firefighter gear

Published online before print August 5, 2015, doi:10.1177/0040517515596926Textile Research Journal May 2016vol. 86 no. 7 710-726

Emiel A DenHartog1
Marika A Walker2
Roger L Barker1

1Textile Protection and Comfort Center, North Carolina State University, USA
2Department of Kinesiology, University of Georgia, USA

Emiel A DenHartog, Textile Protection and Comfort Center, North Carolina State University, 2401 Research Drive, Campus Box 8301 Raleigh, NC, 27695-8301, USA. Email: eadenhar@ncsu.edu

Abstract -- In most types of protective clothing heat strain is an important issue. The wildland firefighter clothing system in the USA has seen no major revision over the last decades. In this project the wildland firefighter clothing system was studied at the material and the systems level. On the sweating guarded hot plate and the sweating thermal manikin effects of different base layers (cotton and modacrylic) and meta-aramid outer layers of different fabric weights were evaluated. Then, a human subject trial was performed on a limited set of clothing systems to validate the results from materials and manikin testing. The clothing systems were composed of relevant materials for wildland firefighters with extra configurations added to explore the effects of the highest and lowest levels of protection. All measurement techniques were reverted to a calculation of the total heat loss (THL), as predicted from the hot plate and the manikin and compared to the calculated heat loss from the human subjects.
The prediction of the heat strain, based on the sweating guarded hot plate only, gives a large overestimation of the actual heat loss in humans. The currently used standard in the USA that utilizes THL values has no link to actual human heat loss. The manikin showed much better comparison to the human data in absolute terms, but in general underestimated heat loss and showed worse overall correlation to the human heat loss data than the hot plate values.

http://trj.sagepub.com/content/early/2015/08/05/0040517515596926.abstract


 

Determination of the thermal protective performance of clothing during bench-scale fire test and flame engulfment test: Evidence from a new index

Published online before print April 21, 2015, doi: 10.1177/0734904115581620

Journal of Fire Sciences May 2015 vol. 33 no. 3 218-231

Jiazhen He1,2

Min Wang1,2

Jun Li1,2

1Protective Clothing Research Center, Fashion Institute, Donghua University, Shanghai, P.R. China

2Key Laboratory of Clothing Design and Technology, Donghua University, Ministry of Education, Shanghai, P.R. China

Jun Li, Protective Clothing Research Center, Fashion Institute, Donghua University, NO. 1882, West Yan-an Road, Shanghai 200051, P.R. China. Email: lijun@dhu.edu.cn

Abstract -- The protective performance of heat- and flame-resistant materials can be studied using a bench-scale test or a full-scale instrumented manikin test. However, there are some limitations of these evaluation methods. The existing bench-scale test could not be applied entirely to assess the thermal protective performance of fabrics if the exposure duration is fixed, while the existing manikin test only provides limited information about the local difference in thermal insulation. This study developed a new index of maximum attenuation factor to second-degree burn injury (maximum attenuation factor) as an improved quantitative method of the thermal protective performance, and then investigated the use of maximum attenuation factor during the bench-scale test as well as the manikin test. It demonstrated that the calculations of maximum attenuation factor were highly repeatable. In both the bench-scale and the manikin test, strong correlations were found between the results derived from the proposed method and the measurements from the existing test method. The results between the bench-scale test and the manikin test can also be compared as a united index.

http://jfs.sagepub.com/content/33/3/218.abstract


 

Evaluation of a hybrid personal cooling system using a manikin operated in constant temperature mode and thermoregulatory model control mode in warm conditions

Dandan Lai1

Fanru Wei2

Yehu Lu2

Faming Wang1⇑

1Soochow University, China

2College of Textile and Clothing Engineering, China

Faming Wang, Soochow University, Office 2215, 908 Building, 199 Ren'ai Road, Suzhou, 215123, China. Email: dr.famingwang@gmail.com

Abstract -- In this study, the cooling effect of a portable hybrid personal cooling system (PCS) was investigated on a sweating manikin operated in the constant temperature (CT) mode and the thermoregulatory model control (TMC) mode. Both dry (i.e., no sweating) and wet manikin tests (i.e., sweating) were performed in the CT mode in a warm condition (30℃, 47% relative humidity (RH), air velocity va = 0.4 m/s). For the TMC mode, two case studies were simulated: light work condition (30℃, 47% RH, air velocity va = 0.15 m/s, duration: 60 min, metabolic rate: 1.5 METs) and construction work condition (30℃, 47% RH, va = 1.0 m/s, 40 min exercise [5.5 METs] and 20 min rest [1.2 METs]). Four test scenarios were selected: fans off with no phase change materials (PCMs) (i.e., Fan-off, the Control), fans on with no PCMs (i.e., Fan-on), fans off with fully solidified PCMs (i.e., PCM+Fan-off) and fans on with fully solidified PCMs (i.e., PCM+Fan-on). Under the dry condition, the cooling rate in PCM+Fan-off during the initial stage (e.g., 55 and 50 W for the first 15 min and 20 min, respectively) was higher than that in Fan-on (i.e., 45 ± 1 W); under the wet condition, the cooling rate in PCM+Fan-off (e.g., 45 W for 10 min) was much lower than that in Fan-on (i.e., 282 ± 1 W). The hybrid PCS (i.e., PCM+Fan-on) provided a continuous strong cooling effect. Simulation results indicated that ventilation fans or PCMs alone could provide sufficient cooling while doing light work. For the intensive work condition, the PCS in all three scenarios (i.e., PCM+Fan-off, Fan-on and PCM+Fan-on) exhibited beneficial cooling, and the hybrid PCS showed an optimized performance in alleviating heat strain during both exercise and recovery periods. It was thus concluded that the PCS could effectively remove body heat in warm conditions for moderate intensive activities.

Thermetrics equipment used: Newton Thermal Manikin

http://trj.sagepub.com/content/early/2015/12/15/0040517515622152.abstract


 

A new approach to quantify the thermal shrinkage of fire protective clothing after flash fire exposure

Published online before print July 19, 2015, doi:10.1177/0040517515595028Textile Research Journal April 2016vol. 86 no. 6 580-592

Min Wang1,2,3

Xiaohui Li1,2,3Jun Li1,2,3⇑

Bugao Xu4

1Fashion Institute, Donghua University, P.R. China

2Protective Clothing Research Center, Donghua University, P.R. China

3Key Laboratory of Clothing Design and Technology, Donghua University, Ministry of Education, P.R. China

4School of Human Ecology, The University of Texas at Austin, USA

Jun Li, Protective Clothing Research Center, Fashion Institute, Donghua University, No.1882, West Yan-an Road, Shanghai 200051, P.R. China. Email: lijun@dhu.edu.cn

Abstract -- Fire protective clothing made of inherent flame resistant materials shrinks easily when exposed to flash fire. This thermally induced shrinkage affects the thermal protective performance. Methods to evaluate the thermal shrinkage of fire protective garments are under development and there are currently no documentary standards available. The aim of this paper is to provide an effective method to accurately determine the shrinkage magnitude of fire protective clothing after flash fire exposure. This method involved a portable three-dimensional (3D) body scanner that could be mounted into the flame chamber to capture the 3D images of the nude and clothed manikin immediately before and after exposure. Based on the advanced post-processing techniques, the 3D images of the clothed manikin pre- and post-exposure were compared, and thermal shrinkage of the garment was characterized by three parameters, namely garment surface area change and volume and thickness change of the air layers entrapped between the manikin and garment. This method was supposed to provide basic knowledge for the quantitative research into the effect of thermal shrinkage on thermal protective performance.

http://trj.sagepub.com/content/86/6/580.abstract


 

Effects of moisture content and clothing fit on clothing apparent ‘wet’ thermal insulation: A thermal manikin study

Published online before print April 20, 2015, doi:10.1177/0040517515580527Textile Research Journal January 2016 vol. 86 no. 1 57-63

Faming Wang1,2⇑Wen Shi1

Yehu Lu1

Guowen Song3

Rene Michel Rossi4

Simon Anaheim4

1Laboratory for Clothing Physiology and Ergonomics, Soochow University, China

2University of Alberta, Canada

3Iowa State University, USA

4EMPA, Switzerland

Faming Wang, Soochow University, Suzhou, Suzhou, 215021, China. Email: faming.wong@gmail.com

Abstract -- ‘Wet’ thermal insulation, defined as the thermal insulation when clothing gets partially or fully wet, is an important physical parameter to quantify clothing thermal comfort. As the water/sweat gradually occupies the intra-yarn and inter-yarn air voids of the clothing material, the clothing intrinsic thermal insulation will be diminished and, hence, contribute to the loss of total insulation. In cold conditions, a loss in total thermal insulation caused by sweating may result in an inadequate thermal insulation to keep thermal balance and eventually leads to the development of hypothermia and cold injuries. Therefore, it is imperative to investigate the effect of clothing fit and moisture content on clothing ‘wet’ insulation. In this study, the ‘wet’ thermal insulation of three two-layer clothing ensembles was determined using a Newton thermal manikin. Four levels of moisture content were added to the underwear: 100, 200, 500 and 700 g. The clothing apparent ‘wet’ thermal insulation under different testing scenarios was calculated and compared. A third-degree polynomial relationship between the reduction in ‘wet’ thermal insulation and the moisture content added to underwear was obtained. Further, it was evident that the clothing fit has a minimal effect on the apparent ‘wet’ thermal insulation. The findings may have important applications in designing and engineering functional cold weather clothing and immersion suits.

Thermetrics equipment used: Newton Thermal Manikin

http://trj.sagepub.com/content/86/1/57.abstract


 

Thermal protection retention of fire protective clothing after repeated flash fire exposure

Published online before print July 15, 2015, doi: 10.1177/1528083715594977

Journal of Industrial Textiles September 2016 vol. 46 no. 3 737-755

Min Wang1,2,3

Jun Li1,2,3⇑

1Fashion Institute, Donghua University, Shanghai, P.R. China

2Protective Clothing Research Center, Donghua University, Shanghai, P.R. China

3Key Laboratory of Clothing Design and Technology, Donghua University, Ministry of Education, Shanghai, P.R. China

Jun Li, Protective Clothing Research Center, Fashion Institute, Donghua University, Shanghai 200051, P.R. China. Email: lijun@dhu.edu.cn

Abstract -- Fire protective clothing worn by the emergency responders may be exposed to intensive heat condition time and time again during a firefighting work. In this research, the level of thermal protection retained by the fire protective clothing after repeated exposures to flash fire was investigated from bench-scale test to full-scale test. A thermal protective performance tester and an instrumented manikin with a transverse motion system device which was capable of simulating the action of running across the flame were used for the exposure test. Physical properties (mass, thickness, thermal shrinkage, tear strength) and thermal protective property of the test specimens were examined after each exposure. The results showed that repeated heat exposures resulted in continuous decrease of mechanical performance of the fabrics. The thermal protective performance of fabrics with good thermal dimensional stability such as polybenzimidazole/Kevlar and flame resistant cotton decreased after exposure. For the fabrics with severe thermal shrinkage such as Nomex IIIA and polysulfonamide, the thermal protective performance was improved due to the increase of fabric thickness induced by thermal shrinkage. However, this positive effect of thermal shrinkage diminished in the manikin test as it decreased the air gap size between the garment and flame manikin. The thermal protective property of Nomex IIIA garment exhibited continuous decrease after repeated exposures. This study was expected to provide new sights for the performance evaluation and application of fire protective clothing.

http://jit.sagepub.com/content/46/3/737.abstract


 

Thermal Manikin Evaluation of Gender Sweat Differences While Wearing a Ballistic Vest

Published online before print October 9, 2015, doi:10.1177/0887302X15609433Clothing and Textiles Research JournalApril 2016 vol. 34 no. 2 94-108

Tanya Domina1⇑Su Kyoung An1

Patrick George Kinnicutt2

1Department of Human Environmental Studies, Central Michigan University, Mt. Pleasant, MI, USA

2Department of Computer Science, Central Michigan University, Mt. Pleasant, MI, USA

Tanya Domina, Department of Human Environmental Studies, Central Michigan University, 205 Wightman, Mt. Pleasant, MI 48859, USA. Email: tanya.domina@cmich.edu

Abstract -- The purpose of this research was to determine if gender-related thermoregulatory differences impacted relative humidity levels in the microclimate while wearing a unisex ballistic vest. Data was collected using a sweating thermal manikin customized to simulate high-intensity sweat rates. Sensors were used to collect microclimate data between the uniform layers. The male and female thermal manikin exhibited no significant differences in microclimate data in the layers of the back of the uniform while wearing the ballistic vest. There was a significant statistical difference between the male and female manikin for the frontal region with women exhibiting lower RH values. Without the ballistic vest, the female manikin exhibited significantly lower RH values in the microclimate region, both front and back. There were no significant differences in RH values for the male thermal manikin with versus without the ballistic vest.

http://ctr.sagepub.com/content/34/2/94.abstract

Thermetrics equipment used: Newton Thermal Manikin


 

Thermal and water vapor transport properties of selected lofty nonwoven products

Published online before print July 5, 2016, doi: 10.1177/0040517516654104

Textile Research Journal July 5, 2016 0040517516654104

Geoffrey RS Naylor1⇑

Cheryl A Wilson2

Raechel M Laing2

1CSIRO, Australia

2University of Otago, New Zealand

Geoffrey RS Naylor, CSIRO, 75 Pigdons Road, Waurn Ponds, Victoria 3216, Australia. Email: geoff.naylor@csiro.au

Abstract -- The mechanism of dry heat flow through lofty nonwoven structures (i.e. thermal resistance) as occurs in quilts has been established. By contrast, there is a scarcity of published information on the water vapor transport properties. This work explores the thermal and water vapor transport properties of a number of different quilt samples with a focus on identifying fiber type effects. Both commercial product and matched laboratory samples were examined. Steady-state thermal resistance and water vapor resistance measurements confirmed that both properties are primarily determined by sample thickness and are largely independent of fiber type. Experiments were also undertaken to observe transient effects. Test samples were initially equilibrated on a ‘dry’ guarded hotplate (35 ± 0.1℃) in a low relative humidity environment (45%). The relative humidity was then rapidly increased to 85%. Compared to polyester, wool samples exhibited a large reduction in the heat flux required to maintain the hotplate temperature. This transient peak lasted for in excess of 1000 seconds. The magnitude of this transient peak in heat flux was proportional to the quantity of wool in the sample and is believed to be associated with the known exothermic nature of water vapor absorption by wool as relative humidity increases. Based on the published values of the heat of water absorption of wool it is estimated that this additional transient heat source is significant relative to a typical human resting metabolic rate and so the effect may be of practical relevance in the bedding environment.

http://trj.sagepub.com/content/early/2016/07/05/0040517516654104.abstract


 

Impact of substrate on water vapor resistance of naturally weathered coated fabrics

Published online before print August 24, 2016, doi: 10.1177/0040517516657055

Textile Research Journal August 24, 2016 0040517516657055

Ivana Salopek Čubrić1⇑

Vesna Marija Potočić Matković1

Zenun Skenderi1

Anita Tarbuk2

1Faculty of Textile Technology, Department of Textile Design and Management, University of Zagreb, Croatia

2Faculty of Textile Technology, Department of Textile Chemistry and Ecology, University of Zagreb, Croatia

Ivana Salopek Čubrić, Department of Textile Design and Management, University of Zagreb, Faculty of Textile Technology, Prilaz baruna Filipovića 28a, Zagreb, Croatia. Email: ivana.salopek@ttf.hr

Abstract -- The aim of the study was to investigate changes of water vapor resistance of coated fabrics with different knitted substrates. For the study different knitted structures were designed and produced, while the conditions for the coating process were kept constant. All structures were exposed to natural weathering in the summer and winter seasons. Thus, the experimental setup enabled the comparison of changes in water vapor resistance of various structures as a result of aging, as well as giving an insight into the differences in resistance after aging in different seasons. After exposure, changes in fabric mass per unit area, thickness and water vapor resistance were observed. The outcomes of the study gave a good insight into the behavior of coated fabrics and may be used when protecting coated materials in order to improve their performance.

http://trj.sagepub.com/content/early/2016/08/24/0040517516657055.abstract

Thermetrics equipment used: sweating guarded hotplate (model SGHP-8.2)


 

A review of garment ventilation strategies for structural firefighter protective clothing

Published online before print July 22, 2015, doi: 10.1177/0040517515595029

Textile Research Journal May 2016 vol. 86 no. 7 727-742

Meredith McQuerry⇑

Emiel Den Hartog

Roger Barker

Kevin Ross

Textile Protection and Comfort Center, North Carolina State University, Raleigh, NC, USA

Meredith McQuerry, Textile Protection and Comfort Center, North Carolina State University, Campus Box 8301, Raleigh, NC 27695, USA. Email: mlcinnam@ncsu.edu

Abstract

The purpose of this review article is to evaluate ventilation, within protective clothing, for its benefit towards heat loss. Literature from ventilation studies in the sports apparel, outdoor clothing, military, chemical, and firefighter protection industries will be examined for future research opportunities. Challenges to ventilation such as garment placement, protection, wearability, and durability will be discussed in the context of turnout suits. Ventilation designs will be considered for further evaluation in structural firefighter turnout garments. This article serves as the first comprehensive review of ventilation literature for structural firefighter turnout ensembles. Researchers, technologists, and functional apparel designers may all benefit from such a review. The value of ventilation and its potential contribution to current firefighter turnout research will be discussed.

http://trj.sagepub.com/content/86/7/727.abstract

Thermetrics equipment used: Newton Thermal Manikin