Experimental Study on the Efficacy of a Novel Personal Cooling Vest Incorporated with Phase Change Materials and Fans

In recent years, personal cooling has aroused much attention because it can achieve both localized high-level thermal comfort and build energy savings. In this study, a novel hybrid personal cooling vest (PCV) incorporated with phase change materials (PCMs) and ventilation fans was developed, and its efficacy was investigated by human trials in a hot-humid climate chamber. Three generally accepted indices (thermal load, Q; thermal sensation, TS; and physiological strain index, PSI) and a new proposed index (cumulative heat storage, CHS) during human trials were comparatively studied between the two human trial groups, i.e., the PCV group (wearing the PCV) and the CON group (without PCV). Results found that TS, PSI, and CHS were significantly reduced by the PCV, which suggests that the PCV can significantly improve both the perceptual and physiological strain. In addition, a strong linear relationship (r2 = 0.8407) was found between the proposed index of CHS with PSI, which indicates the applicability and reliability of CHS for assessing physiological heat strain.

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Peak indoor air temperature reduction for buildings in hot-humid climate using phase change materials

Case Studies in Thermal Engineering ◽

10.1016/j.csite.2020.100762 ◽

2020 ◽

Vol 22 ◽

pp. 100762

Author(s):

Zeyad Amin Al-Absi ◽

Mohd Isa Mohd Hafizal ◽

Mazran Ismail ◽

Ahmad Mardiana ◽

Azhar Ghazali

Keyword(s):

Phase Change ◽

Air Temperature ◽

Indoor Air ◽

Phase Change Materials ◽

Humid Climate ◽

Temperature Reduction ◽

Hot Humid Climate

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Energy Saving and Charging Discharging Characteristics of Multiple PCMs Subjected to Internal Air Flow

Fluids ◽

10.3390/fluids6080275 ◽

2021 ◽

Vol 6 (8) ◽

pp. 275

Author(s):

Ahmed J. Hamad

Keyword(s):

Phase Change ◽

Energy Saving ◽

Air Temperature ◽

Temperature Control ◽

Phase Change Materials ◽

Energy Savings ◽

Heating System ◽

Air Heating ◽

Room Model ◽

Model Temperature

One essential utilization of phase change materials as energy storage materials is energy saving and temperature control in air conditioning and indirect solar air drying systems. This study presents an experimental investigation evaluating the characteristics and energy savings of multiple phase change materials subjected to internal flow in an air heating system during charging and discharging cycles. The experimental tests were conducted using a test rig consisting of two main parts, an air supply duct and a room model equipped with phase change materials (PCMs) placed in rectangular aluminum panels. Analysis of the results was based on three test cases: PCM1 (Paraffin wax) placed in the air duct was used alone in the first case; PCM2 (RT–42) placed in the room model was used alone in the second case; and in the third case, the two PCMs (PCM1 and PCM2) were used at the same time. The results revealed a significant improvement in the energy savings and room model temperature control for the air heating system incorporated with multiple PCMs compared with that of a single PCM. Complete melting during the charging cycle occurred at temperatures in the range of 57–60 °C for PCM1 and 38–43 °C for PCM2, respectively, thereby validating the reported PCMs’ melting–solidification results. Multiple PCMs maintained the room air temperature at the desired range of 35–45.2 °C in the air heating applications by minimizing the air temperature fluctuations. The augmentation in discharging time and improvement in the room model temperature using multiple PCMs were about 28.4% higher than those without the use of PCMs. The total energy saving using two PCMs was higher by about 29.5% and 46.7% compared with the use of PCM1 and PCM2, respectively. It can be concluded that multiple PCMs have revealed higher energy savings and thermal stability for the air heating system considered in the current study.

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Predicted Medium Vote Thermal Comfort Analysis Applying Energy Simulations with Phase Change Materials for Very Hot-Humid Climates in Social Housing in Ecuador

Sustainability ◽

10.3390/su13031257 ◽

2021 ◽

Vol 13 (3) ◽

pp. 1257

Author(s):

Luis Godoy-Vaca ◽

E. Catalina Vallejo-Coral ◽

Javier Martínez-Gómez ◽

Marco Orozco ◽

Geovanna Villacreses

Keyword(s):

Thermal Comfort ◽

Phase Change ◽

Social Housing ◽

Energy Demand ◽

Phase Change Materials ◽

Thermal Sensation ◽

Electricity Consumption ◽

Different Types ◽

Climate Influences ◽

Energy Simulations

This work aims to estimate the expected hours of Predicted Medium Vote (PMV) thermal comfort in Ecuadorian social housing houses applying energy simulations with Phase Change Materials (PCMs) for very hot-humid climates. First, a novel methodology for characterizing three different types of social housing is presented based on a space-time analysis of the electricity consumption in a residential complex. Next, the increase in energy demand under climate influences is analyzed. Moreover, with the goal of enlarging the time of thermal comfort inside the houses, the most suitable PCM for them is determined. This paper includes both simulations and comparisons of thermal behavior by means of the PMV methodology of four types of PCMs selected. From the performed energy simulations, the results show that changing the deck and using RT25-RT30 in walls, it is possible to increase the duration of thermal comfort in at least one of the three analyzed houses. The applied PCM showed 46% of comfortable hours and a reduction of 937 h in which the thermal sensation varies from “very hot” to “hot”. Additionally, the usage time of air conditioning decreases, assuring the thermal comfort for the inhabitants during a higher number of hours per day.

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Thermal storage effect of radiant floor cooling system using phase change materials in the hot and humid climate of Indonesia

Building and Environment ◽

10.1016/j.buildenv.2021.108442 ◽

2021 ◽

pp. 108442

Author(s):

Haruka Kitagawa ◽

Takashi Asawa ◽

Tetsu Kubota ◽

Andhang Rakhmat Trihamdani ◽

Hiroshi Mori

Keyword(s):

Phase Change ◽

Phase Change Materials ◽

Cooling System ◽

Thermal Storage ◽

Storage Effect ◽

Humid Climate ◽

Hot And Humid Climate ◽

Radiant Floor Cooling System

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Performance Improvement of a Household Refrigerator using Phase Change Material

Journal of Manufacturing Engineering ◽

10.37255/jme.v16i1pp032-041 ◽

2021 ◽

Vol 16 (1) ◽

pp. 032-041

Author(s):

Pradeep N ◽

Somesh Subramanian S

Keyword(s):

Energy Storage ◽

Phase Change ◽

Phase Change Material ◽

Phase Change Materials ◽

Energy Savings ◽

Storage System ◽

Thermal Storage ◽

Latent Heat Storage ◽

Peak Loads ◽

Change Material

Thermal energy storage through phase change material has been used for wide applications in the field of air conditioning and refrigeration. The specific use of this thermal storage has been for energy storage during low demand and release of this energy during peak loads with potential to provide energy savings due to this. The principle of latent heat storage using phase change materials (PCMs) can be incorporated into a thermal storage system suitable for using deep freezers. The evaporator is covered with another box which has storage capacity or passage through phase change material. The results revealed that the performance is increased from 3.2 to 3.5 by using PCM.

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Thermo-physical characteristics of building integrated phase change materials (PCM) and their applicability to energy efficient homes

10.32920/ryerson.14660997 ◽

2021 ◽

Author(s):

Omar Siddiqui

Keyword(s):

Compressive Strength ◽

Phase Change ◽

Phase Change Materials ◽

Energy Savings ◽

Physical Characteristics ◽

Comfort Level ◽

Thermal Mass ◽

Lower Phase ◽

Physical Test ◽

The Impact

The applicability of utilizing a variety of thermal mass including phase change materials with commonly used building materials is investigated through the use of simulations and physical testing. The thermal performance and occupant comfort potential of a novel solid-solid phase change material, known as Dal HSM, is compared and contrasted to commonly available forms of thermal mass. Detailed experimentation is conducted to successfully integrate Dal HSM with gypsum and concrete. The measurement of physical characteristics such as compressive strength and modulus of rupture is conducted to ensure that the PCM-composite compound retains the structural integrity to be utilized in a typical building. The use of thermal mass in the Toronto Net Zero house was found to contribute to energy savings of 10-15% when different types of thermal mass were used. The comfort level of the indoor occupants was also found to increase. The performance of Dal HSM was found to be comparable to a commercially available PCM known as Micronal in the heating mode. The cooling mode revealed that Dal HSM provided slightly lower energy savings when compared to Micronal due to a lower phase transition temperature and latent heat. The performance of physical test revealed a decrease in the compressive strength as the concentration of Dal HSM was increased in the PCM-gypsum specimens. Tests were also performed to analyze the impact of increasing the PCM concentration on the flexural strength of PCM-gypsum composite.

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Evaluation of Phase Change Materials for Personal Cooling Applications

Clothing and Textiles Research Journal ◽

10.1177/0887302x211053007 ◽

2021 ◽

pp. 0887302X2110530

Author(s):

Lennart Teunissen ◽

Emiel Janssen ◽

Joost Schootstra ◽

Linda Plaude ◽

Kaspar Jansen

Keyword(s):

Phase Change ◽

Phase Change Materials ◽

Cooling Capacity ◽

Packaging Material ◽

Inorganic Salts ◽

Cooling Power ◽

Water Based ◽

Use of phase change materials in nano-concrete for energy savings

Smart Nanoconcretes and Cement-Based Materials ◽

10.1016/b978-0-12-817854-6.00015-5 ◽

2020 ◽

pp. 351-381

Author(s):

Tung Chai Ling ◽

Sarra Drissi ◽

Kim Hung Mo

Keyword(s):

Phase Change ◽

Phase Change Materials ◽

Energy Savings

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Energy refurbishment of existing buildings through the use of phase change materials: Energy savings and indoor comfort in the cooling season

Applied Energy ◽

10.1016/j.apenergy.2013.08.045 ◽

2014 ◽

Vol 113 ◽

pp. 990-1007 ◽

Cited By ~ 178

Author(s):

Fabrizio Ascione ◽

Nicola Bianco ◽

Rosa Francesca De Masi ◽

Filippo de’ Rossi ◽

Giuseppe Peter Vanoli

Keyword(s):

Phase Change ◽

Phase Change Materials ◽

Energy Savings ◽

Existing Buildings ◽

Indoor Comfort

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Thermal sensation under high-intensive exercise in naturally ventilated gymnasiums in hot-humid areas of China: Taking basketball players for example

Indoor and Built Environment ◽

10.1177/1420326x20978275 ◽

2020 ◽

pp. 1420326X2097827

Author(s):

Xiaodan Huang ◽

Qingyuan Zhang ◽

Zhangyuan Wang ◽

Xiaoli Ma

Keyword(s):

Evaluation System ◽

Thermal Sensation ◽

Systematic Evaluation ◽

Air Velocity ◽

Humid Climate ◽

Basketball Players ◽

Basketball Game ◽

Sport Activities ◽

Hot Humid Climate ◽

Radiant Temperature

As a public building for exercises and entertainments, gymnasiums play an important role in people's daily life. In regions with hot-humid climate, thermal sensation in gymnasiums is directly related to the human health as well as energy consumption. However, little can be found in the systematic evaluation system reported for thermal sensation of athletes in gymnasium in hot-humid climate regions; therefore, there is a need to develop a thermal sensation model for evaluating thermal sensation of athletes partaking sports in these environments. In this study, a field survey on thermal sensation of players in a basketball game was carried out in a naturally ventilated gymnasium in Guangzhou, China. The results showed that the human physiology and thermal sensation of subjects were highly different during active sport state. Moreover, the thermal sensation vote was increased with a rise in the air temperature, the mean radiant temperature and humidity ratio, while thermal sensation vote was reduced with an increase in the air velocity. The metabolic rate, systolic blood pressure and skin temperature were shown to have a positive correlation with the thermal sensation vote. According to the analysis, a predictive thermal sensation model, which has been developed by this study to estimate the thermal sensation under high-intensive sport activities in gymnasiums in regions with a high temperature and high humidity, was evaluated and validated.

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