Auxiliary Heating Device Research Articles

Particle Number Concentration and SEM-EDX Analyses of an Auxiliary Heating Device in Operation with Different Fossil and Renewable Fuel

Pollution from road vehicles enters the air environment from many sources. One such source could be if the vehicle is equipped with an auxiliary heater. They can be classified according to whether they work with diesel or gasoline and whether they heat water or air. The subject of our research series is an additional heating system that heats the air, the original fuel is gasoline. This device has been built up in a modern engine test bench, where the environmental parameters can be controlled. The length of the test cycle was chosen to be 30 min. The tested fuels were E10, E30, E100 and B7. A 30-min operating period has been chosen in the NORMAL operating mode of the device as a test cycle. The focus of the tests was particle number concentration and soot composition. The results of the particle number concentration showed that renewable fuel content significantly reduces the number concentration of the emitted particles (9.56 × 108 #/cycle for E10 vs. 1.65 × 108 #/cycle for E100), while B7 causes a significantly higher number of emissions than E10 (3.92 × 1010 #/cycle for B7). Based on the elemental analysis, most deposits are elemental carbon, but non-organic compounds are also present. Carbon (92.18 m/m% for E10), oxygen (6.34 m/m% for E10), fluorine (0.64 m/m% for E10), and zinc (0.56 m/m% for E10) have been found in the largest quantity of deposits taken form the combustion chamber.

Multi-hole coupling power monitor with tapered sub-waveguide for dual-frequency high-power gyrotron

In magnetically confined fusion plasmas, a gyrotron is an essential auxiliary heating device for generating and sustaining plasma through electron cyclotron resonance heating owing to its ability to generate high-power microwaves. Microwaves emitted from a gyrotron are often transmitted through waveguides, and the transmitted power is monitored by a power monitor with a multi-hole directional coupler at the miter bend of the transmission line. Recently, a high-power dual-frequency gyrotron has been installed and operated in the Large Helical Device. A power monitor with good sensitivity to multiple frequencies is required to monitor the power transmission of the different frequencies at the same transmission line. In order to realize the power monitor, which can couple with the multiple-frequency microwaves, we focused on a sub-waveguide shape in the power monitor and investigated the influence of the tapered sub-waveguide by conducting electromagnetic simulations using a simple model. We also performed the high-power test using a power monitor with a tapered sub-waveguide. The experimental result was different from the simulation, but enough receiving power was obtained at both 116 and 154 GHz.

A study on the effect of metal skeleton auxiliary heating device on microwave heating efficiency of batch Al2O3 ceramics

In order to improve the microwave heating efficiency of the batch Al2O3 ceramics, according to generalized transmission line theory in this paper, the relationship between the amplitude and phase of the electromagnetic field in the microwave resonant cavity was deduced by using the distribution relationship of voltage and current on the transmission line. SiC auxiliary heating plate was used as the auxiliary heating device. Based on the reflection principle of metal material to electromagnetic wave, the metal skeleton was added to SiC auxiliary heating plate. The COMSOL multi-physics field simulation software was used for simulation. The results showed that the addition of metal materials could change the intensity and distribution of the electromagnetic field on SiC auxiliary heating plate and Al2O3 ceramic blocks, so as to affect the microwave energy utilization rate of heating area and the heating efficiency of Al2O3 ceramic blocks. The numerical simulation results showed that the microwave energy utilization rate of the heating area could be improved by adding the metal skeleton in the SiC auxiliary heating plate and employing a reasonable design, so as to improve the overall heating efficiency of the Al2O3 ceramic blocks. Compared with the traditional SiC auxiliary heating device, the heating efficiency of Al2O3 ceramic blocks was improved by 26.4%, and the overall temperature uniformity was improved by 12.5%.

Design and Life Cycle Assessment of small-scale medical waste incinerator equipped with Porous Radiant Burner for remote areas

ABSTRACT In this paper, the design of a Small-scale Medical Waste Incinerator (SMWI) equipped with an LPG-operated Porous Radiant Burner (PRBLPG) is presented as a solution for disposing of medical waste generated in remote areas. Based on simple mass and heat balance analysis, SMWI having primary and secondary chambers with a volume of 1 and 0.754 m3 is designed. The proposed SMWI is evaluated for its environmental impact by performing a Life Cycle Assessment (LCA) and compared with an SMWI equipped with an Electric Heater (SMWI–EH). The total primary energy required for the construction of SMWI is 48285.56 MJ. It is found that the damage caused by the operation of PRBLPG in SMWI is lesser when compared to that of an Electric Heater (EH). In SMWI–PRB, LPG consumption contributed to about 17488.27 kg CO2−eq in the global warming category, whereas in the case of SMWI–EH, electricity consumption contributed to about 243766.11 kg CO2−eq. The operation of SMWI–PRB showed a reduction of about 54% in the resource utilisation category in comparison with SMWI–EH. The results obtained from the LCA study indicated that PRBLPG is a better option as an auxiliary heating device in SMWI than EH due to its environmental superiority.

Enhancing the performance of a greenhouse drying system by using triple-flow solar air collector with nano-enhanced absorber coating

In this research, the impacts of utilizing nano-embedded absorber coating in an auxiliary heater of a greenhouse drying system on the thermal and drying performances have been surveyed empirically. In this context, triple-flow solar air collectors with and without CuO nano-enhanced absorber coating have been designed and manufactured. Designed collectors then integrated to even-span greenhouse dryers to be used as an auxiliary heating device. In the experiments, greenhouse dryers have been tested with and without auxiliary heaters at constant flow rate which is 0.014 kg s−1. According to the experimental findings, utilizing triple-flow solar air heating device with and without nano-embedded paint decreased the drying time as 35.71% and 26.66%, respectively. Thermal and exergetic efficiencies for newly developed collectors were found between the range of 70.39–75.11% and 9.05–10.18%, respectively. In addition, specific energy consumption values were decreased by using collectors with and without nano-enhanced modification from 2.51 to 2.11 and from 2.61 to 2.18 kWh/kg, respectively. Attained outcomes of this study showed the successful utilization of nano-enhanced absorber coating in the auxiliary heating system of the greenhouse dryer.

Development and status of high-voltage power supply and integrated control system for KSTAR ECH system

Korea Superconducting Tokamak Advanced Research (KSTAR) is planning to install an auxiliary heating device comprising six electron cyclotron (EC) systems with a total of 6 MW of radiofrequency (RF) output. Two EC systems were operated in the 2019 KSTAR campaign. To compensate the shortcomings identified during the operation of the previous two systems, the power supply was upgraded and a new integrated control system was developed. A power supply is a device that affects the RF beam quality generated by the gyrotron of an EC system and ensures efficient operation. Features such as real-time operation, a crowbar system, and a redundancy module were added to the upgraded power supply. An integrated control system is an important device that protects a gyrotron and supports stable operation. The overall structure of the integrated control system was changed to enable real-time operation, and functions such as retrigger and shot-information were added. In the 2020 KSTAR campaign, a new EC system including the upgraded power supply and the new integrated control system was added, and a total of three EC systems were operated. The new EC system was successfully employed at KSTAR. In this paper, we explain in detail the upgraded power supply and the new integrated control system and show and discuss the results of their application to the 2020 KSTAR campaign.

Improving the performance of an active greenhouse dryer by integrating a solar absorber north wall coated with graphene nanoplatelet-embedded black paint

Greenhouse drying systems are sustainable and clean applications for preserving agricultural crops. In this work, a single-slope greenhouse drying system has been modified with solar absorber and thermally insulated north wall. Also, the designed and manufactured north wall has been coated with graphene nanoplatelet-embedded black paint. Greenhouse dryers with north wall and nano-embedded north wall modifications have been experimentally compared with a conventional greenhouse dryer. Main goal of this research is to upgrade the performance of a greenhouse drying system without using any auxiliary heating device and complex structural components. According to the experimental outcomes, drying time was reduced as 75 and 90 min by utilizing north wall and nano-enhanced north wall, respectively. Furthermore, exergy efficiencies of greenhouse dryers with north wall and nano-enhanced north wall were attained as 4.67% and 5.38%, respectively while this value for conventional greenhouse dryer obtained between 2.61 and 2.70%. Moreover, utilizing graphene nanoplatelets in black paint improved the specific moisture extraction rate as 40% in comparison to conventional greenhouse dryer.

MEMS-based dual temperature control measurement method for thermoelectric properties of individual nanowires

Abstract

Evaluating potentials of passive solar heating renovation for the energy poverty alleviation of plateau areas in developing countries: A case study in rural Qinghai-Tibet Plateau, China

Energy poverty refers to a situation that people cannot access and use energy safely. It is a major challenge for the global energy system because of its negative impacts on household income, health, education, gender equality and environmental conditions. To solve this problem, many countries advocate the development and promotion of passive solar technology, but the effectiveness of them for energy poverty mitigation has not been evidenced. Therefore, based on empirical studies in the rural areas of Qinghai-Tibet Plateau, this paper aims at investigating the effectiveness of passive solar heating renovation to alleviate energy poverty in rural plateau areas. Specifically, this paper compared and analyzed the coal consumption and indoor air quality during the heating period before and after the renovation of a single-storey building. Further, based on the IES-VE numerical simulation, this paper analyzed the impact of building envelope structure performance on indoor air temperature. The results show that after building renovation, the coal consumption during the heating period could be reduced by 97 kg/week, while the indoor average temperature of two bedrooms were increased by 4.8 °C and 1.7 °C respectively. Setting up the coal stove as an auxiliary heating device, can alleviate the defects of insufficient heating of passive solar energy technology, and indoor temperature could be further improved. However, indoor air quality was lowered because of the high PM2.5 concentration. In contrast, improving envelope performance could further improve the average temperature of two bedrooms and the sunspace to 16.7 °C, 15.9 °C and 15.6 °C, meeting the requirements of indoor space heating. In general, passive solar heating could achieve satisfactory results, but to alleviate energy poverty effectively in rural plateau areas, further attention should be paid to other technical, economic, social and policy issues.

Experimental Evaluation of the Ability of an Auxiliary Heating Device to Reduce the Condensation Risk around Built-in Wardrobes of Apartment Buildings in Winter

Recently, there has been an increase in the condensation and mould problems of apartment buildings in Korea owing to the high insulation and high air-tightness performance of buildings, which increase energy savings. Condensation is generally found in winter on furniture back panels and adjacent surfaces of the wall, floor, and ceiling. These problems are related to the weather conditions and indoor room conditions in winter. To solve these problems, an auxiliary heating device that can be installed was developed. The purpose of this study was to evaluate condensation risk in the condensation vulnerable areas around built-in furniture of apartment buildings by installing an auxiliary heating device. The experimental results reveal that condensation risk can be reduced by comparing the thermal environment around the built-in furniture with and without installation of an auxiliary heating device in winter. Furthermore, they reveal that it is possible to increase the surface temperature of vulnerable areas around built-in wardrobe by applying an auxiliary heating device to minimize condensation problems by using a minimum device.

Thermal performance of indirect forced convection solar dryer and kinetics analysis of mango

In this paper, an indirect forced convection solar dryer (IFCSD) with auxiliary heating device has been presented for drying mango. The dryer consists of the evacuated tube solar air collector, three phase inverter fan, auxiliary heating device, drying chamber, and automatic control system. Moreover, the influence of different drying air temperatures on the dryer performance, the drying characteristic and the drying kinetics of mango slices in this dryer have been investigated. The experimental results showed that the temperatures at four different locations of the drying chamber were varied within a narrow band. Meanwhile, the average thermal efficiency of IFCSD was between 30.9% and 33.8%, the specific moisture extraction rate (SMER) was 1.67 (kg water/kWh) with the drying temperature of 52 °C. In addition, results revealed that the Page's model was the most appropriate for describing the drying kinetics of mango slices in IFCSD. The effective moisture diffusivity (Deff) values of mango slices were obtained from the Fick’s diffusion equation varying from 6.41 × 10−11 to 1.18 × 10−10m2/s, over the temperature range of 40–52 °C. Furthermore, results revealed that Deff values increased with the increasing of drying air temperatures, due to the increase of heating energy would increase the activity of water molecules of mango slices. Thus, this study contributed to provide the basic theoretical and experimental data support for the follow-up research.

The development of data acquisition and processing application system for RF ion source

As the key ion source component of nuclear fusion auxiliary heating devices, the radio frequency (RF) ion source is developed and applied gradually to offer a source plasma with the advantages of ease of control and high reliability. In addition, it easily achieves long-pulse steady-state operation. During the process of the development and testing of the RF ion source, a lot of original experimental data will be generated. Therefore, it is necessary to develop a stable and reliable computer data acquisition and processing application system for realizing the functions of data acquisition, storage, access, and real-time monitoring. In this paper, the development of a data acquisition and processing application system for the RF ion source is presented. The hardware platform is based on the PXI system and the software is programmed on the LabVIEW development environment. The key technologies that are used for the implementation of this software programming mainly include the long-pulse data acquisition technology, multi-threading processing technology, transmission control communication protocol, and the Lempel–Ziv–Oberhumer data compression algorithm. Now, this design has been tested and applied on the RF ion source. The test results show that it can work reliably and steadily. With the help of this design, the stable plasma discharge data of the RF ion source are collected, stored, accessed, and monitored in real-time. It is shown that it has a very practical application significance for the RF experiments.

Co-Production Performance Evaluation of a Novel Solar Combi System for Simultaneous Pure Water and Hot Water Supply in Urban Households of UAE

Water is the most desirable and sparse resource in Gulf cooperation council (GCC) region. Utilization of point-of-use (POU) water treatment devices has been gaining huge market recently due to increase in knowledge of urban population on health related issues over contaminants in decentralized water distribution networks. However, there is no foolproof way of knowing whether the treated water is free of contaminants harmful for drinking and hence reliance on certified bottled water has increased worldwide. The bottling process right from treatment to delivery is highly unsustainable due to huge energy demand along the supply chain. As a step towards sustainability, we investigated various ways of coupling of membrane distillation (MD) process with solar domestic heaters for co-production of domestic heat and pure water. Performance dynamics of various integration techniques have been evaluated and appropriate configuration has been identified for real scale application. A solar combi MD (SCMD) system is experimentally tested for single household application for production 20 L/day of pure water and 250 L/day of hot water simultaneously without any auxiliary heating device. The efficiency of co-production system is compared with individual operation of solar heaters and solar membrane distillation.

Research on a Household Dual Heat Source Heat Pump Water Heater with Preheater Based on ASPEN PLUS

This article proposes a dual heat source heat pump bathroom unit with preheater which is feasible for a single family. The system effectively integrates the air source heat pump (ASHP) and wastewater source heat pump (WSHP) technologies, and incorporates a preheater to recover shower wastewater heat and thus improve the total coefficient of performance (COP) of the system, and it has no electric auxiliary heating device, which is favorable to improve the security of the system operation. The process simulation software ASPEN PLUS, widely used in the design and optimization of thermodynamic systems, was used to simulate various cases of system use and to analyze the impact of the preheater on the system. The average COP value of a system with preheater is 6.588 and without preheater it is 4.677. Based on the optimization and analysis, under the standard conditions of air at 25 °C, relative humidity of 70%, wastewater at 35 °C, wastewater flow rate of 0.07 kg/s, tap water at 15 °C, and condenser outlet water temperature at 50 °C, the theoretical COP of the system can reach 9.784 at an evaporating temperature of 14.96 °C, condensing temperature of 48.74 °C, and preheated water temperature of 27.19 °C.

Classifications of central solar domestic hot water systems

Currently, there are many means by which to classify solar domestic hot water systems, which are often categorized according to their scope of supply, solar collector positions, and type of heat storage tank. However, the lack of systematic and scientific classification as well as the general disregard of the thermal performance of the auxiliary heat source is important to DHW systems. Thus, the primary focus of this paper is to determine a classification system for solar domestic hot water systems based on the positions of the solar collector and auxiliary heating device, both respectively and in combination. Field-testing data regarding many central solar DHW systems demonstrates that the position of the auxiliary heat source clearly reflects the operational energy consumption. The consumption of collective auxiliary heating hot water system is much higher than individual auxiliary heating hot water system. In addition, costs are significantly reduced by the separation of the heat storage tank and the auxiliary heating device.

도시 거주 남자 대학생의 자각적 내한내열성과 체온조절 행동

This study was conducted to investigate the thermoregulatory behavior of young males in terms of self-identified thermal tolerance. We recruited 436 male students from Seoul (<TEX>$24.0{\pm}4.6yr$</TEX> in age, <TEX>$175.3{\pm}5.5cm$</TEX> in height, <TEX>$70.1{\pm}10.6kg$</TEX> in body mass, and <TEX>$23.0{\pm}2.7$</TEX> in BMI) in accordance with four types of self-identified thermal tolerance: 1) tolerable of both cold and heat, BCH (N=15); 2) heat tolerable only, HTO (N=118); 3) cold tolerable only, CTO (N=162); and 4) neither cold nor heat tolerable, NCH (N=141). The questionnaire consisted of 55 questions regarding preference to cold or heat environment, seasonal thermoregulatory behaviors including clothing habits, seasonal sleeping environments, health care/physical fitness, and anthropometric items. The results showed that: 1) BCH preferred less auxiliary heating devices, gloves/hats, or thermal underwear in winter and had very few experiences with cold/heat injuries or catching a cold, whereas NCH showed the opposite behavior and experiences as BCH; 2) thermoregulatory behaviors were not symmetrical between summer and winter. Most male students preferred cold beverage/foods to using cooling devices to lower body temperature in summer, whereas auxiliary heating devices were preferred to warm beverage/foods to maintain body temperature in winter; 3) thermoregulatory behaviors of NCH had more items in common with HTO than CTO, while the behaviors of BCH were more closely related to CTO than the behaviors of BCH were more closely related to CTO than HTO. Overall, we confirmed that thermoregulatory behaviors were apparently classified by self-identified thermal tolerance, and such behaviors could be adjusted by improving cold or heat tolerance.

흡열판에 돌출형 삼각 개구부가 설치된 가정용 태양열 공기가열기의 열성능에 대한 실험적 연구

A solar air heater was designed for supplementary domestic heating. The absorber plate had a series of protruding notches which had triangular openings on the front surface of the absorber plate to direct partial air flow to the rear surface and to enhance the convective heat transfer to the flowing air. The height of the opening as well as the opening configuration was determined by preceding numerical simulations. The experimental model had an absorber plate of 0.78-m width and 1.0-m length which was coated with black paint. The air temperature increased as much as for flow rate when the absorber plate was inclined by for a clear-day solar irradiation of about . The collector efficiency ranged from 69 to 74%. Considering the simplicity of the structure and low manufacturing cost, the solar air heater might have competence as an auxiliary heating device for domestic use. On-site experimental results are presented with discussion for various solar irradiations and air flow conditions.

Modeling and simulation of the PTC heater used in automotive

At present, efforts are made to improve the passenger’s thermal comfort inside the vehicle. The thermal comfort level depends on the air conditioning and heating system. The conventional heating systems use the heat excess delivered by the vehicle’s engine. Nevertheless, this heat excess is insufficient for warming the interior air to a comfort level. In order to improve the conventional heating method, auxiliary heating devices are required. The paper deals with the analysis and measurement of the PTC heater characteristics. A test-bench is described. The heating process inside the vehicle is analyzed and a model and simulations are also presented.

Experiment management system—A way towards a transparent Tokamak

At TEXTOR extensive collaborations with foreign institutes have been established. For a successful collaboration, the participating scientists must be able to plan the experiment in advance. Therefore they need tools to submit and track their experiment proposals and pulse plans. During and after the experiment access to raw and evaluated data of a TEXTOR discharge is needed to analyze TEXTOR data remotely from the home labs. A goal-oriented data analysis needs in addition a various items of data not recorded with conventional data logging. This discharge specific comments and settings are stored in a logbook. At TEXTOR a logbook with different views is implemented for the scientific experiment and the machine operation, respectively. In a further development towards a TEXTOR experiment management system the information of auxiliary heating devices is stored. The electronic logbook is realized by a client/server approach which makes the access independent from the hard- and software on the client side and allows to access the data and data supplements (metadata) by any common web browsers. All information from TEXTOR is accessible for everybody via a uniform resource locator (URL). The concept of the electronic logbook, the first experience and its possibilities for data analysis will be discussed in this paper.

Heating energy reduction of buildings in cold climates

Normal conventional methods of decreasing energy consumption for the heating of buildings are: increasing the insulation thickness, reducing the air leakage of buildings, using special low-energy windows, lowering the room air temperature and recovering heat from exhaust air. Unconventional methods of reducing the energy consumption and peak energy demand for wall heat losses and ventilation, by using low temperature solar heat sources provided by nature or waste heat without a heat pump, that are especially suitable for cold climates are considered. The operation and optimization of these unconventional energy-saving methods are analysed theoretically for different Finnish climatic regions (Helsinki, Sodankylä). The peak power demand that occurs during the coldest days of the year greatly decreases in both regions, which means that the auxiliary heating devices and energy production can be dimensioned much smaller. Both absolute and relative energy savings increase from southern regions to southern regions.