Air Quality and Comfort Characterisation within an Electric Vehicle Cabin in Heating and Cooling Operations

This work is aimed at the experimental characterisation of air quality and thermal profile within an electric vehicle cabin, measuring at the same time the HVAC system energy consumption. Pollutant concentrations in the vehicle cabin are measured by means of a low-cost system of sensors. The effects of the HVAC system configuration, such as fresh-air and recirculation mode, on cabin air quality, are discussed. It is shown that the PM concentrations observed in recirculation mode are lower than those in fresh-air mode, while VOC concentrations are generally higher in recirculation than in fresh-air mode. The energy consumption is compared in different configurations of the HVAC system. The novelty of this work is the combined measurement of important comfort parameters such as air temperature distribution and air quality within the vehicle, together with the real time energy consumption of the HVAC system. A wider concept of comfort is enabled, based on the use of low-cost sensors in the automotive field.

Study and Application of Industrial Thermal Comfort Parameters by Using Bayesian Inference Techniques

This paper focuses on the use of Bayesian networks for the industrial thermal comfort issue, specifically in industries in Northern Argentina. Mined data sets that are analyzed and exploited with WEKA and ELVIRA tools are discussed. Thus, networks giving the predictive value of thermal comfort for different pairs of indoor temperature and humidity values according to activity, time, and season, verified in the workplace, were obtained. The results obtained were compared to other statistical models of linear regression used for thermal comfort, thus observing that comfort temperature values are within a same range, yet the network offered more information since a range of options for interior design parameters (temperature/relative humidity) was offered for different work, time, and season conditions. Additionally, if compared with static models of heat exchange, the contribution of Bayesian networks is noted when considering a context of actual operability and adaptability conditions to the environment, which is promising for developing thermal comfort intelligent systems, especially for the development of sustainable settings within the Industry 4.0 paradigm.

No Effect of Cycling Shoe Outsole Stiffness On Sub- and Supra-Maximal Cycling Performance Parameters.

Background: The aim of this study was to test the effects of cycling shoe outsole stiffness on both performance and comfort parameters during sub- and supra-maximal cycling tests. Methods: Two groups of recreational women tested three cycling shoe conditions with differing outsole stiffness. One group of 8 women performed four cycling tests of 3 min composed of two intensities (100 and 140 W) and two pedaling rates (70 and 100 rpm) for each pair of shoes. Metabolic and subjective perception of comfort measurement was evaluated with each shoe. Another group of 12 women performed 6-s all-out sprints against two external resistances (0.4 and 0.7 N/kg) to determine force-velocity relationships with the three cycling shoe conditions. Results: The main findings are that the stiffness of the investigated outsole cycling shoes (i) does not influence cycling performance whatever the test (ii) while the perception of comfort is largely degraded compared to the most flexible shoe. Conclusion: Maximizing stiffness should no longer be of the highest design principal for beginners or recreational women cyclists.

Non-Destructive Possibilities of Thermal Performance Evaluation of the External Walls

Identification of the actual thermal properties of the partitions of building enclosures has a significant meaning in determining the actual energy consumption in buildings and in their thermal comfort parameters. In this context, the total thermal resistance of the exterior walls (and therefore their thermal transmittance) in the building is a major factor which influences its heat losses. There are many methods to determine the total thermal resistance of existing walls, including the quantitative thermography method (also used in this study). This paper presents a comparison of the calculated total thermal resistance values and the measured ones for three kinds of masonry walls without thermal insulation and the same walls insulated with expanded polystyrene boards. The measurements were carried out in quasi-stationary conditions in climate chambers. The following three test methods were used: the temperature-based method (TBM), the heat flow meter method (HFM) and the infrared thermography method (ITM). The measurement results have been found to be in good agreement with the theoretically calculated values: 61% of the measured values were within 10% difference from the mean value of total thermal resistance for a given external wall and 79% of the results were within 20% difference. All of the used measuring methods (TBM, HFM and ITM) have proven to be similarly approximate in obtained total thermal resistances, on average between 6% and 11% difference from the mean values. It has also been noted that, while performing measurements, close attention should be paid to certain aspects, because they can have a major influence on the quality of the result.

Transfer and Friction Characteristics of Sports Socks Fabrics Made of Synthetic Fibres in Different Structures

Sports socks fabrics produced from polyester, polypropylene, their modified forms Thermocool®, Polycolon®, in three different structures (single jersey, piquet, terry) were investigated for their skin-fabric friction, permeability (air and water vapour), liquid absorption and transfer (absorbency, immersion, absorption capacity, wetback and drying) properties. According to the results, the effect of structure is dominant for frictional characteristics but focusing on the material, polypropylene created a bulkier and lighter structure with lower friction coeffi¬cients, an advantage for sports socks. The effect of structure is greater than the material also for some thermal comfort parameters, e.g. air permeability and absorbency. Focusing on materials, besides their better liquid transfer characteristics, modified forms of both fibres had worse performances for air permeability and absor¬bency compared to their standard forms. Absorption capacity, wetback and drying performances were related to fabric density besides the polyester’s higher regain capacity. While Polycolon® had superiority for wetback performance against standard polypropylene, this was not the case for Thermocool®; however, both modified materials showed apparent superiority for drying periods. Piquet structures were advantageous for absorption capacity and wetback performances for polypropylene. For sports socks parts, specific needs can be met by changing the fabric structure. Considering the materials, polypropylene and Polycolon® can be recommended for both thermal and tactile aspects.

Carnauba (copernicia prunifera) straw as an alternative bedding material for dairy cows housed in a Compost barn system

ABSTRACT The replacement of bedding in compost dairy barns (CB) comprises a recurrent management practice, but bedding materials are often not readily available in all regions and the choice of alternative materials is necessary. The objective was to evaluate the thermal attributes of carnauba straw (CS) bedding in compost dairy barn facilities. Environmental monitoring operations were performed at a commercial farm located in Northeast Brazil. Mini weather stations were used to evaluate environmental variables. The THI was evaluated as one of the comfort parameters. Analysis of the spatial distribution of bed surface temperature (BST) in the CB was performed using geostatistical techniques. The cows remained out of the comfort zone according to THI results. The BST indicated satisfactory performance and from the thermal point of view can be used as alternative bedding material in CB facilities. However, it was observed that the CS showed fast biomass degradation compared to conventional materials, widely known. In addition, inadequate temperature values (< 45°C) were found in the deeper of the CS bed, signaling higher risks of pathogenic microbial activity. Additional studies are needed for searching the proper management plans that increase the life span of the bed formed by carnauba straw.

An Efficient Method to Compute Thermal Parameters of the Comfort Map Using a Decreased Number of Measurements

This paper presents an empirical approach to design ideal workplaces using the PMV-PPD (predicted mean vote–predicted percentage dissatisfied) method set in ISO 7730 in terms of thermal comfort. The key concept behind our method is that the overall employee satisfaction might be improved if they can select the most suitable desk based on their personal comfort preferences. To support desk sharing, we designed a comfort map toolkit, which can visualize the distribution of comfort parameters within office spaces. The article describes the steps to create comfort maps with methods already widely used, as well as a new one developed by our research team, including the measurement procedures and the theoretical background required.

The comfort parameters in indoor air of sports facilities with different ventilation regimes

Introduction: In Portugal, during COVID19pandemic, sport and fitness facilities were closed. When lockdown has been lifted, in order to prevent the spread of infection, indoor sport facilities were subject to specific regulations that limited indoor occupancy as well as manner of air ventilation. This study aims to analyze the impacts of these ventilation restrictions on indoor air comfort parameters in sport fitness facilities. Methodology: Temperature (T; ºC), relative humidity (RH; %), and carbon dioxide (CO2) were continuously monitored (41 days; spring and autumn) in four fitness centers situated in Oporto metropolitan area: two of them under normal ventilation conditions (i.e. before lockdown; NV1 and NV2) and two of them under temporary restrictions for indoor ventilations and occupancy (RV1 and RV2). Results and Discussion: Under normal ventilation conditions, T in fitness centers slightly varied (in NV1:22-25 ºC; NV2: 20-23 ºC) but in both clubs the comfort recommendations (18-25 ºC) were fulfilled. On contrary, RH were below guideline values (55-75%) in NV1 (47-54%) whereas at NV2 (66-73%) it fulfilled the recommendations. When specific health regulations took place, mean T ranges were similar in both clubs (RV1: 21-23 ºC; RV2:21-23 ºC) but they both exceeded recommended comfort levels (16-21 ºC). Mean RH were in accordance with the legislative values, but the very high temporal maxima (up to 75 and 89%) indicate the possible discomforts the that exercisers might have experienced. Concerning the CO2, the obtained results showed that indoorlevels decreased when specific health restrictions were in force (11-121%) most likely due imposed guidelines for human occupancy. Conclusions: The restrictions for ventilation and human occupancy positively impacted indoor levels of CO2. However, T and RH were on several occasions outside the recommended comfort levels, especially during group activity classes. As regular exercising in environmental conditions, such as elevated T and increased RH can cause health discomforts, these parameters should be carefully maintained within the recommended ranges even under restricted ventilation scenarios.