Globe Thermometer Research Articles

Three-dimensional heat transfer of globe thermometers in indoor environments controlled by radiant systems

The theoretical basis of a globe thermometer is based on the lumped parameter method. In highly heterogeneous radiation environments, e.g., outdoor solar radiation and indoor heavily asymmetric radiation, the lumped parameter assumption is likely to be unreasonable. Asymmetric radiation is the inherent feature of radiant cooling indoor environments. Therefore, it is necessary to evaluate the influence of the asymmetric radiation of radiant cooling indoor environments on the thermal behaviour of globe thermometers. In this study, a three-dimensional heat transfer model for globe thermometers is established. The computational fluid dynamics method and the finite element method are used to solve the thermo-fluid field of the globe thermometer. The proposed theoretical model was validated against the results of experiments performed in a radiant cooling room and the data from existing literature. Some case studies were performed to analyse the thermal behaviour of various globe thermometers with different diameters and materials. The temperatures of metal globe thermometers were found to be uniform, whereas the temperature differences in the 50 mm and 150 mm acrylic globe thermometers were both 1.2 °C. Compared to metal globe thermometers, the air temperature deviations in the 50 mm and 150 mm acrylic globe thermometers were 0.6 °C and 0.4 °C, respectively. Thus, the asymmetric radiation of common radiant cooling indoor environments has a slight effect on the thermal behaviour of acrylic globe thermometers. This study is conducive to understanding the heat transfer mechanism of globe thermometers in indoor environments controlled by radiant systems.

Wet bulb globe temperatures and risk of acute kidney injury among Central American workers

Background/Aim: There is an epidemic in Central America of chronic kidney disease of unknown etiology (CKDu), also referred to as Mesoamerican Nephropathy (MeN). MeN prevalence is high among agricultural workers and other occupations involving physical labor in hot working environments, such as brickmaking. Chronic heat stress and volume depletion are hypothesized to be important risk factors. Methods: The MesoAmerican Nephropathy Occupational Study (MANOS) is a prospective cohort study of 569 Salvadoran and Nicaraguan workers designed to investigate environmental and occupational risk factors for MeN. MANOS participants represent five industries: sugarcane, corn, plantain, brick manufacturing, and construction. At baseline, workers were monitored for three consecutive work days. Wet bulb globe temperature (WBGT) was collected every minute during these work shifts using wet bulb globe thermometers. Participants provided serum samples pre- and post-shift on the third day of baseline monitoring. Results: At baseline, the mean estimated glomerular filtration rate (eGFR) of MANOS participants was 106.7 mL/min/1.73 m2. Fifty three (9.3%) had an eGFR < 60 mL/min/1.73 m2. Fourteen participants met serum creatinine-based criteria for cross-shift acute kidney injury (AKI) during baseline monitoring. The mean percent increase in serum creatinine across work shifts was 5.3%. In El Salvador, WBGT was measured on forty-six separate days of workplace monitoring. On these days, an average of 54.7% of the work shift temperatures monitored after 6am were above 28°C, the American Conference of Governmental Industrial Hygienists Threshold Limit Value for moderate work at a continuous work rate. In unadjusted analyses, mean WBGT temperature on the third day of monitoring was positively associated with percent increase in serum creatinine (1.3% increase per 1°C) among Salvadoran workers. Conclusions: MANOS participants experience workplace temperatures that regularly exceed health-protective guidelines. Exposures to these high temperatures may increase the risk of AKI among these workers.

Physiological parameters of male goats raised under tropical climate conditions (Brazil)

This study evaluated the adaptive capacity and variations in physiological parameters of four male goats originate from a temperate region (Alpine breed) in a tropical climate over twelve months. The ambient temperature, relative humidity, and temperature via a black globe thermometer were evaluated to calculate the black globe temperature and humidity index; they were collected five times during the day, three times during the week, and during the four annual seasons. Every fortnight throughout the experimental period, respiratory and heart rates as well as rectal and surface temperatures of the animals were measured in the morning, and blood samples were acquired for hormonal levels (cortisol, T3, and T4) and complete blood count. There was a difference between the mean values of surface temperature, respiratory rate, hormones, and some hematological parameters (total protein and monocytes) between the seasons (P<0.05). However, no differences were observed in cases of heat stress, based on the fact that physiological parameters were within normal and expected limits for goats. Thus, it is concluded that the male goats of the Alpine breed, when reared intensively, maintain homeothermia and are greatly adaptable to the conditions of the tropical climate.

A Comprehensive Model for Estimating Heat Vulnerability of Young Athletes.

Current methods for estimating heat vulnerability of young athletes use a heat index (HI) or a wet bulb globe thermometer (WBGT), neither of which fully include the environmental or physiological characteristics that can affect a person’s heat budget, particularly where activity occurs on a synthetic surface. This study analyzed and compared the standard methods, HI and WBGT, with a novel and more comprehensive method termed COMFA-Kid (CK) which is based on an energy budget model explicitly designed for youth. The COMFA model was presented at the same time to demonstrate the difference between a child and an adult during activity. Micrometeorological measurements were taken at a synthetic-surfaced football field during mid-day in hot environmental conditions. Standard methods (HI and WBGT) indicated that conditions on the field were relatively safe for youth to engage in activities related to football practice or games, whereas the CK method indicated that conditions were dangerously hot and could lead to exertional heat illness. Estimates using the CK method also indicated that coaches and staff standing on the sidelines, and parents sitting in the stands, would not only be safe from heat but would be thermally comfortable. The difference in thermal comfort experienced by coaches and staff off the field, versus that experienced by young players on the field, could affect decision making regarding the duration and intensity of practices and time in the game. The CK method, which is easy to use and available for modification for specific conditions, would lead to more accurate estimates of heat safety on outdoor synthetic surfaces in particular, and in sports with a high prevalence of heat illness such as football, and should be considered as a complementary or alternative preventive measure against heat.

RELATIONSHIP BETWEEN WORK CLIMATE AND FATIGUE OF THE LABOUR AT PT. SHINAM JAYA ABADI IN WAJOK HULU OF MEMPAWAH REGENCY

Hot work climate may affect the conditions of workers that potentially reduce work productivity and efficiency. Based on an examination conducted by the Pontianak Hyperkes Service Unit, there was a company that had a working climate above the NAV, namely PT. Shinam Jaya Abadi. The purpose of this study was to investigate the relationship between temperature, humidity, and wind speed with fatigue in the workforce at PT. Shinam Jaya Abadi, Wajok Hulu Village, Pontianak Regency. This present research was a quantitative study with 97 samples. It applied proportional random sampling. The data collecting techniques were measurement, interview and observation. The instruments were the August Psychometer, Anemometer and Globe Thermometer, questionnaires and check list sheets. The data were analysed using the Chi Square statistical test. The research found out that there was a relationship of temperature (p = 0.009) with air humidity (p = 0.010), and there was no relationship of wind speed (p = 0.134) with fatigue in the workforce at PT. Shinam Jaya Abadi, Wajok Hulu Village, Mempawah District. The company was recommended to control the work climate that passed through NAB and to provide drinking water that has been given salt 0.2% gram / liter, it added ventilation, regulated the length of work and rest periods. The workers needed to carry out routine checks before work, and to use APD.
 Keywords : Work climate, work fatigue

UTCI field measurements in an urban park in Florence (Italy)

Abstract The aim of this study is to evaluate human thermal comfort in different green area settings in the city of Florence by using the Universal Thermal Climate Index (UTCI). Field measurements of air temperature, solar radiation, relative humidity, wind speed and black globe thermometer were collected during hot summer days in various parts of Cascine Park, the biggest urban park in Florence (Italy). UTCI was evaluated over different surfaces (asphalt, gravel and grass) completely exposed to the sun or shaded by a large lime tree (Tilia × europaea). The results showed strong differences in UTCI values depending on the exposure to tree shade, while no significant difference was found among ground-cover materials when all surfaces were equally exposed to solar radiation. Future studies are needed to investigate the microclimatic effects of different tree species on UTCI.

Accuracy of Mean Radiant Temperature Derived from Active and Passive Radiometry

The concept of the mean radiant temperature (Tmrt) allows the study of radiative exchanges between a human and its environment. It presupposes that the radiant effects on the person of the actual environment, which is generally heterogeneous, and the virtual environment, which is defined as homogeneous, are identical. ISO 7726 specifies the required accuracy in Tmrt as input of rational thermal indices, outdoors ±5 (K). Tmrt accounts for the radiant heat absorbed by skin/clothing from the shortwave (SW) and longwave (LW) spectral bands. Most of the radiant components are isotropic. However, there are anisotropic SW components; namely the direct irradiance and under clear or partly obstructed skies a significant circumsolar fraction (fcs) in the diffuse irradiance. Both originate from the close proximity of the solar disk. This study highlights the effect of fcs on Tmrt. In the scope of human biometeorology a standing body posture is standard. For unidirectional irradiances its radiant cross-section varies dependent on the solar altitude. Active radiometry in deriving Tmrt is based on measured irradiances. One method is the Klima-Michel-Modell (KMM) that uses readily available measurements from standard meteorologically radiant observations. KMM references Fanger’s area projection factors that are derived from precise measurements of real humans. Thus, KMM serves as reference in evaluation of further methods. One is the six-directional instrument (Tmrt,r,6−Dir). Slightly simplifying a standing human, it represents a subject as a rectangular solid. Tmrt,r,6−Dir is derived based on measured irradiances incident on the vertical and horizontal planes. In passive radiometry the energy balance equation of a black globe thermometer is solved that leads to Tmrt,Tg,BG. fcs significantly impacts Tmrt with noticeably reduced values for high and increased for low solar altitudes. Hence, accounting for fcs is essential for the accuracy of Tmrt. For KMM an extension to an existing algorithm is provided in order to include fcs into the Tmrt calculation that results in Tmrt,r,KMM. For Tmrt,r,6−Dir the radiant cross-section of the solid depends to a minor extent on its azimuth relative to the solar azimuth. As a result Tmrt,r,6−Dir slightly scatters compared to Tmrt,r,KMM. However, it remains within ±2 (K). Tmrt,Tg,BG compared to Tmrt,r,KMM complies only at night with the ISO 7726 bin of ±5 K. Tmrt,Tg,BG significantly overestimates Tmrt,r,KMM during the daytime, because of its greater SW absorptance compared to skin/clothing and to a smaller extent because the standing posture is represented by a sphere. Particularly in sunny conditions, Tmrt,Tg,BG is subject to considerable variance. Thus, outdoors during the daytime, Tmrt,Tg,BG is unable to serve as an appropriate input for the calculation of rational-based thermal indices.

Post-occupancy evaluation of outdoor thermal comfort in hot arid zone

Abstract Human comfort and healthy environments lie at the core of every debate about outdoor spaces nowadays. Thermal comfort is a vital concern for planners and designers in order to produce a healthy and thermally comfortable environment, since the influence of different climates and user groups has been found to greatly alter the range of responses for thermal comfort calculations. This requires Post-Occupancy Evaluation (POE) with an integration of the appropriate outdoor thermal comfort (OTC) index. This paper presents the results of a detailed assessment for the OTC in hot arid zone (HAZ) using the most suitable thermal index. A case study was selected from Effat Campus, Jeddah, Saudi Arabia, to represent the HAZ. Subjective assessment employed the physiological equivalent temperature (PET) and the predictive mean vote (PMV) thermal indices in analysing the results of online and self-directed questionnaires while objective assessment employed a hand-held anemometer that was used to measure wind speed, whereas the wet bulb globe temperature (WBGT) SD Card Logger with a black globe thermometer 75 mm in diameter and emissivity of 0.95 was used to measure the globe temperature. The physical measurements were later used to calculate the mean radiant temperature (MRT) and consequently the PET index using RayMan Software. The results confirmed the significance of the shading strategy on OTC. The study revealed that there is no percentage as shading is permitting people to use the space; otherwise, in hot arid zone, the space would be completely unusable under the sun while the PET is more suitable than the PMV index.

Calculation Of The Radiation Temperature Of The Urban Development Environment

The radiation ambient temperature is one of the microclimatic indicators of urban areas, which determines the safe stay of people in them during the warm period of the year. The ability of artificial coatings to accumulate and radiate heat energy should be taken into account in making competent urban planning decisions to eliminate or reduce the additional heat load on the urban environment. The calculation of radiation temperatures of the environment contributes to the adoption of environmentally safe urban planning decisions of specific areas. Using such "tools" as changing the orientation of the urban object to the cardinal directions, thermal properties of anthropogenic coatings, their concentration (density), and exposure, it is possible to control the radiation power of the surrounding surfaces, and, accordingly, the value of radiation temperatures. Research with the use of the globe thermometer confirms change in the radiation temperatures. In this case, the elementary area can be replaced with the reduced site, which will be the limit when calculating the irradiance coefficients of the required accuracy from the elements of urban development. The size of the reduced site is usually a uniform architectural element of the facade plane, for example, the size of a standard window or half of the average wall panel, etc., which is convenient for assigning the materials of the above sites radiation absorption coefficients and calculating or measuring the surface temperature. A method for calculating radiation temperatures, which is based on determining the irradiation coefficients from the globe thermometer to the surrounding fences of an imaginary space (parallelepiped) of the yard, with due regard for their surface temperatures, is proposed.

A novel comprehensive workflow for modelling outdoor thermal comfort and energy demand in urban canyons: Results and critical issues

In the energy simulation of buildings there has been little focus on their impact on the microclimate; simulation tools have usually dealt either with building or with outdoor simulation, and only recently these aspects are being interconnected. Within this framework, the paper describes a novel simulation workflow developed in the Grasshopper environment, where the Ladybug Tools are used to model the mutual relations amongst urban microclimate, building energy performance and outdoor thermal comfort. With reference to an urban canyon located in Catania, Southern Italy, the workflow – by coupling the indoor and the outdoor thermal field – provides both the dynamic thermal load of the buildings overlooking the canyon and the parameters needed to measure the outdoor comfort perceived by pedestrians. In comparison to other existing approaches, this workflow offers significant flexibility and makes it possible to perform a parametric investigation of the effects of different design solutions on both the indoor and the outdoor environment.The outdoor Mean Radiant Temperature calculated through the model is compared to on-site measurements performed with a black globe thermometer during two different days in the summer. The comparison suggests good agreement in the shaded areas of the canyon, but a non-negligible overestimation in sunlit areas. These results have driven the authors to a critical insight into the algorithms implanted in the Ladybug Tools, and have helped to highlight some critical issues that will be further investigated in upcoming research.

Globe thermometer free convection error potentials

For thermal comfort research, globe thermometers have become the de facto tool for mean radiant temperature, tr, measurement. They provide a quick means to survey the radiant environment in a space with nearly a century of trials to reassure researchers. However, as more complexity is introduced to built environments, we must reassess the accuracy of globe measurements. In particular, corrections for globe readings taking wind into account rely on a forced convection heat transfer coefficient. In this study, we investigate potential errors introduced by buoyancy driven flow, or free convection, induced by radiant forcing of a black globe’s surface to a temperature different from the air. We discovered this error in an experimental radiant cooling system with high separation of air to radiant temperature. Empirical simulations and the data collected in a radiant cooling setup together demonstrate the influence of free convection on the instrument’s readings. Initial simulation and data show that tr measurements neglecting free convection when calculating tr from air temperatures of 2 K above tr could introduce a mechanism for globe readings to incorrectly track air temperatures. The experimental data constructed to test this hypothesis showed the standard correction readings are 1.94 ± 0.90 °C higher than the ground truth readings for all measurements taken in the experiment. The proposed mixed convection correction is 0.51 ± 1.07 °C higher than the ground truth, and is most accurate at low air speeds, within 0.25 ± 0.60 °C. This implies a potential systematic error in millions of measurements over the past 30 years of thermal comfort research. Future work will be carried out to experimentally validate this framework in a controlled climate chamber environment, examining the tradeoffs between accuracy and precision with globe thermometer measurements.

Development of physiological human model considering mist wettedness for mist-spraying environments

The thermal state of the human body is closely related to thermal sensations and thermal comfort and can be estimated using a physiological human model. However, the feasibility of its prediction models in a mist-spraying environment has not been examined. The present study confirmed the applicability of existing prediction models (two-node model (2NM) and three-node model (3NM)) in outdoor and mist-spraying environments. Additionally, the evaporative heat loss caused by mist wetting in the human body (mist wettedness)—which has been overlooked—was measured using a heating globe thermometer controlled at the skin-temperature level, and on the basis of the results, the existing prediction models were modified. In the outdoor environment, the existing and modified models predicted the skin temperature identically, with errors of 0.30 °C (2NM) and 0.24 °C (3NM), for 10 min. In the mist-spraying environment, the skin-temperature results for the existing models stabilized and did not reflect the continuously decreasing experimental results, but the modified models reflected the continuously decreasing tendency of the experimental skin-temperature results, with errors of 0.52 °C (2NM) and 0.56 °C (3NM). When the effective area factor (ηmist = 0.5) of the mist droplets was applied to the modified prediction models, the mist wettedness contributions to the total heat loss from the body surface were 40.4% (2NM) and 37.9% (3NM). Therefore, the mist wettedness was identified as a significant environmental factor affecting the heat loss on the human body, and these models can provide better understandings of the physical phenomena in mist-spraying environments.

Assessment of black globe thermometers employing various sensors and alternative materials

The black globe temperature (Tg) is employed in thermal comfort studies. It is mainly used to compute the Mean Radiant Temperature (MRT) required in bioclimatic analysis. A set of low cost Black Globe Thermometers (BGT) was developed to establish a suitable combination of temperature transducers, materials and globe diameters. The dynamic and static responses of the BGT were studied. A total of 18 BGT was deployed along with a data acquisition system based in the Arduino open-source platform. It was analyzed the influence of the globe material (metallic and polyethylene), globe diameter (100 mm and 67 mm for the metallic and 78 mm for polyethylene) and six types of temperature transducers (K type thermocouple, infrared temperature sensor, thermistor, RTD and two semiconductor-based transducers). It was observed that Tg estimation and response time were transducer and stimuli dependent. The BGT presents good responses for indoor measurements and it was established that the most accurate combination was achieved by the DS18B20 digital temperature sensor with a metallic globe of 67 mm of diameter.

Estimating outdoor mean radiant temperature in a humid subtropical climate

Mean Radiant Temperature (Tmrt) is a decisive parameter in determining outdoor thermal comfort in human biometeorology. The estimation of Tmrt in an outdoor environment is however complex. This study attempts to determine Tmrt by the six directional method and recalibrate the mean convection coefficient of the gray globe for ease of use in the humid subtropical climate. Six directional short - wave and long-wave radiant flux densities have been measured and analysed across different urban open spaces — plaza, promenade and green. The study presents the relationship between Tmrt and the radiant flux densities. Tmrt values obtained via the six directional method show a statistically significant difference with those obtained using mean convection coefficients discussed in literature. Consequently, the mean convection coefficient of the gray globe thermometer has been recalibrated for use in the humid subtropical climate. Tmrt estimated via the recalibrated mean convection coefficient agrees well with the results of the six directional method.

Correcting the Error in Measuring Radiation Received by a Person: Introducing Cylindrical Radiometers.

Most human energy budget models consider a person to be approximately cylindrical in shape when estimating or measuring the amount of radiation that they receive in a given environment. Yet, the most commonly used instrument for measuring the amount of radiation received by a person is the globe thermometer. The spherical shape of this instrument was designed to be used indoors where radiation is received approximately equally from all directions. But in outdoor environments, radiation can be strongly directional, making the sphere an inappropriate shape. The international standard for measuring radiation received by a person, the Integral Radiation Measurement (IRM) method, yields a measure of the Mean Radiant Temperature (Tmrt). This method uses radiometers oriented in the four cardinal directions, plus up and down. However, this setup essentially estimates the amount of energy received by a square peg, not a cylinder. This paper identifies the errors introduced by both the sphere and the peg, and introduces a set of two new instrument that can be used to directly measure the amount of radiation received by a vertical cylinder in outdoor environments. The Cylindrical Pyranometer measures the amount of solar radiation received by a vertical cylinder, and the Cylindrical Pyrgeometer measures the amount of terrestrial radiation received. While the globe thermometer is still valid for use in indoor environments, these two new instruments should become the standard for measuring radiation received by people in outdoor environments.

Risk Analysis in a Tropical Forest Wood Exploration and Processing System in Mato Grosso State, Brazil

Forestry and logging activities in tropical regions are commonly carried out in inappropriate thermal conditions, due to the hot and humid climate, demanding from the worker high energy expenditure and physical effort. They often operate and handle machines and equipment that produce high levels of noise and vibration, and adopt postures that can be harmful to the body, given the constant lifting, handling and transport of loads above tolerable limits. The objective of this study was to evaluate the exposure of workers to risks in a rainforest harvesting and processing system in northern Mato Grosso State, Brazil. The study was conducted in two forest management areas and four processing industries. Occupational heat exposure was assessed and a qualitative analysis of noise and vibration was performed in the two study areas. Occupational exposure to heat was performed by determining the Wet Bulb Index and Globe Thermometer (IBUTG), while the qualitative analysis of noise and vibration was performed with the application of a Risk Analysis methodology. The results indicate that the values of the wet bulb index and globe thermometer (IBUTG), obtained every hour of the working day in the activities of the timber industry and wood processing, correspond to values above the tolerance limit, as standardized. The condition most likely to be harmful to health was found in the exposure to noise by workers in the wood processing industry, especially in operations related to the logging stages, where the risk was categorized as intolerable. With respect to exposure to vibration, the risk was higher in chainsaw operations in logging. In this case, it was possible to qualitatively analyze which occupational exposure limit (OEL) would be exceeded when the machine was in operation, representing risks to workers’ health and safety. It is concluded that there is a need to adopt control measures, since the risk exposure levels were in a range that poses a risk to workers’ health.

HYSTERESIS AND THERMAL INERTIA OF SPHERES OF ALTERNATIVE MATERIALS FOR BLACK GLOBE THERMOMETERS

ABSTRACT This research was conducted with the objective of evaluating the thermal inertia and hysteresis of the following materials in a wind tunnel: hollow copper sphere with 150.0 mm diameter used as standard in globe thermometers, hollow brass sphere with 75.0 mm diameter, and two hollow plastic spheres with 115.5 and 69.7 mm diameter. The results showed that the thermal inertia and hysteresis for the hollow copper sphere were approximately 24 and 28 min, respectively; these values were bigger than those obtained for the other spheres, implying faster responses of these. While there were no statistical differences in the measurements conducted by globe thermometers which are used to indicate the black globe temperature with the different types of spheres mentioned above under indoor environment conditions, i.e., with no wind and solar radiation, the wind causes faster cooling in smaller spheres under outdoor environment conditions, which may denote erroneous interpretations of the measurements at those instants. It was concluded that it is possible to replace the hollow copper sphere of diameter 150 mm by other types of spheres to measure the black globe temperature. However, this requires knowledge of the response times of the spheres as well as corrections to be made in the measurements with respect to the globe thermometer standard.

Drone-assisted infrared thermography for calibration of outdoor microclimate simulation models

Outdoor microclimate modelling is getting popular for estimating comfort conditions in urban environments. Current calibration approaches usually rely on measurements of air temperature for a limited number of points in the study domain, in spite of the fact that it is the Mean Radiant Temperature (Tmrt) the parameter mostly affecting comfort. However, the direct measurement of Tmrt outdoors via the globe thermometer or using the six direction radiation method is prone to errors.To overcome these issues, the present paper proposes a novel method to indirectly improve its estimate based on the use of infrared thermal pictures gathered by drone flights to measure surface temperatures, and then use these values for calibrating numerical models. This novel approach has been demonstrated for a 400 × 400 m2 wide area in the city of Medicina (Italy) and showed a good agreement with ENVI-met simulations, with average and standard deviation values difference between measured and simulated surface temperatures of 1.53 °C and 2.22 °C respectively. The highest differences (up to 19 °C) are found for areas densely covered by vegetation. Further studies are planned to evaluate the goodness of the calibration pixel wise and to propose calibration thresholds based on Tmrt sensitivity.

A field study on application of infrared thermography for estimating mean radiant temperatures in large stadiums

In large-space buildings such as stadiums or auditoriums, the mean radiant temperature (MRT) at an occupant location can be highly influenced by the outdoor thermal environment. Therefore, it is important to measure a wide range of MRT values to understand thermal comfort conditions. This study reports on the importance of MRT measurements when evaluating the thermal environments of large spaces. We present an MRT measurement method using an infrared thermal imaging camera (IR camera). First, MRT measurement methods using a globe thermometer and an IR camera with respect to large spaces were reviewed to assess their limitations and applicability. A method utilizing the IR camera is proposed to enable multiple-location measurements with a single installed device. In our proposed method, MRT values are calculated using angle factors (AF) and mean indoor surface temperatures. A solid-angle algorithm is adopted to calculate AFs at occupant locations using a simplified model of the indoor space. To confirm the applicability of the proposed method in a large space, experiments are conducted using the globe-thermometer method and the IR method. Results show that the MRT values estimated from both methods have similar trends with differences less than 1 °C. The measured surface temperatures using an IR camera show that indoor surface temperatures can be significantly different according to location and orientation. We conclude that the proposed method is capable of measuring MRT values at multiple locations.

Thermal Performance of Plastered Bamboo-Wall

This paper reviews the application of plastered-bamboo wall (PBW) as an alternative wall construction to replace a conventional brick wall, that are evaluated based on thermal aspects. Brick as the material which is composed of a wall has a high value of density. High-density materials generally have a great heat capacity and contribute to raising the ambient air temperature. On a large scale, they can trigger the occurrence of a heat island phenomenon (UHI). PBW is a technique of wall construction, which are composed of bamboo as a frame and mortar as a frame cover. The thickness of the PBW ranges from 5 to 9 cm. PBW has a lower value of density than a brick wall. This study aims to test the thermal performance of PBW based on its constituent framework, which is divided into two groups of specimens, namely; bamboo woven, and bamboo array. The samples were tested in the field and arranged in such a way as to be exposed to solar radiation. In practice, the heat capacity of specimens was identified through its density. Meanwhile, the thermal performance of samples was identified through time lag (TL) by using thermocouple and globe thermometer. All the results indicate that specimens with bamboo array have better time lag value (longer time) than all specimens with bamboo woven.