Heat Extractor Research Articles

Dynamic Control and Performance Evaluation of Microcontroller-Based Smart Industrial Heat Extractor

Dynamic control and performance evaluation of a microcontroller-based smart industrial heat extractor involves the implementation of control strategies and the assessment of its performance under dynamic operating conditions. Performance evaluation aims to assess the effectiveness and efficiency of the microcontroller-based smart industrial heat extractor under dynamic conditions. Industrial heat extraction systems are often complex, involving multiple components, sensors, actuators, and control algorithms. Understanding and modelling the dynamic behaviour of these systems can be challenging, especially when considering factors like heat transfer rates, thermal delays, and interactions between different system elements. The effectiveness of dynamic control is significantly dependent on precise and dependable measurements from sensors. Sensors deployed in industrial settings may encounter severe environmental conditions, which can result in possible inaccuracies, drift, or even malfunctions. The objective of this research is to propose a simulated methodology for verifying the efficacy of a microcontroller-driven intelligent heat extractor utilised in industrial settings. The execution of experiments or tests within industrial environments can be a costly and time-intensive endeavour, and may entail potential hazards. The efficacy of a smart industrial heat extractor in practical industrial settings can be ascertained through the simulation of its evaluation process, thereby mitigating potential risks. The model designed and simulated in this work utilises an integrated temperature sensor to determine the ambient temperature and transmits a signal to the Arduino UNO microcontroller when the temperature sensor detects variant temperatures ranges. The evaluation is performed by comparing the behaviour and performance of the simulated system with predefined performance metrices.

Study on lifting operation of external heat extractor based on tubular balance beam

As a kind of petrochemical catalytic cracking unit, the external heat extractor is one of the key factors restricting the production schedule and time limit. In order to realize the load balance of external heat extractor in the lifting process and avoid the adverse effect of impact force on catalytic cracking performance of large equipment, a method of lifting external heat extractor with tubular balance beam was proposed. At the same time, a kind of seamless steel tube balance beam is designed according to the characteristics of the balance beam and the working conditions of hoisting. Through the stress analysis of the external heat extractor and the strength calculation of the balance beam of seamless steel tube, the rope installation point of the balance beam and the section position of the balance beam are determined, which can provide the theoretical basis and reference value for the failure analysis of large-scale lifting operations and the lifting operations of similar external heat extractor.

Heat Transfer Enhancement in Multiple Pipes Configuration using Different Fluid Mixtures: A Numerical Approach

Abstract A variety of nanofluids flowing through multiple parallel pipes were numerically studied to examine the heat enhancement effects. Due to the advantages they bring in the cooling process, nanofluids have provided a new way to improve the performance of thermal systems. A typical nanofluid is made up of a base fluid, which is generally water, and nanoparticles. Some nanofluids even consist of a combination of two different types of nanoparticles, resulting in a hybrid nanofluid. In this study, we investigate the effectiveness of forced convection using different class of nanofluids, as well as water and Ethylene Glycol as a benchmark to assess the nanofluids performance. The five different fluid used were: water, Ethylene Glycol, 1%vol Al2O3/water, 1%vol (Al2O3-Cu)/water and 1%vol TiO2/water. Each of these fluids were investigated at four flow rates, with a constant inlet temperature through a heat exchanger experiencing a constant heat flux q”. It was found that Ethylene Glycol exhibits a large pressure drop, while being an excellent heat extractor. Of all of the mixtures, 1%vol TiO2/water is found to have the highest thermal efficiency when considering the combined heat extraction and friction coefficient. Such fluid is suitable as a cooling fluid.

Повышение тепловых характеристик радиатора с вертикальным оребрением при использовании аэрозольно-испарительного охлаждения

The paper is dedicated to the new cooling scheme examination where aerosol is injected directly into the air-cooling system and then the evaporated aerosol is collected and redirected back to the inlet ports. It has examined the air-and-water aerosol influence on the heat extractor characteristics and area of the cooling surface of radiator with parallel square fins considering natural convection as well as radiation. Also, the influence of different characteristics has been examined, such as the concentration of water in aerosol, input power of heating, on the characteristics of the heat extractor.

No impact of transgenic cry1Ie maize on the diversity, abundance and composition of soil fauna in a 2-year field trial

Soil fauna play an essential role in the soil ecosystem, but they may be influenced by insecticidal Cry proteins derived from Bacillus thuringiensis (Bt) maize. In this study, a 2-year field trial was conducted to study the effects of transgenic cry1Ie maize, a type of Bt maize (Event IE09S034), on soil fauna, with the near-isogenic line non-Bt maize (Zong 31) as a control. The soil animals were collected with Macfadyen heat extractor and hand-sorting methods, respectively, and their diversity, abundance and community composition were calculated. Then, the effects of maize type, year, sampling time and soil environmental factors on the soil fauna were evaluated by repeated-measures ANOVA, redundancy analysis (RDA) and nonmetric multidimensional scaling (nMDS). Repeated-measures ANOVA showed that the diversity and abundance of the soil fauna were not affected by maize type, while they were significantly influenced by year and sampling time. Furthermore, for both the Macfadyen and hand-sorting methods, RDA indicated that soil fauna community composition was not correlated with maize type (Bt and non-Bt maize) but was significantly correlated with year, sampling time and root biomass. In addition, it was significantly related to soil pH according to the hand-sorting method. nMDS indicated that soil fauna community composition was significantly correlated with year and sampling time; however, it was not associated with maize type. In this study, we collected soil faunal samples according to the Macfadyen and hand-sorting methods and processed the obtained data with ANOVA, RDA, and nMDS in three ways, and our data indicate that transgenic cry1Ie maize (Event IE09S034) had no substantial influence on the diversity, abundance or community composition of the soil fauna.

The Effect of Triangular Protrusions on Geothermal Wellbore Heat Exchanger from Retrofitted Abandoned Oil Wells

The cost to implement geothermal energy is extremely high, due to the requirement of drilling production and reinjection wells. One method to overcome this problem is to retrofit abandoned oil wells with a closed loop system, eliminating the need for drilling entirely. This study is conducted to evaluate the heat transfer performance of the wellbore heat extractor with the triangular protrusions. A two-dimensional axis-symmetry computational model for fluid flow and conjugate heat transfer in the wellbore is developed. The effect of protrusion height, pitch and volume flow rate are evaluated and discussed in view of numerical results. The results suggest that triangular protrusions offer higher heat transfer rate. However, careful consideration should be taken as the pumping power required is higher due to higher pressure drop. The outcome of this study provides a new insight into the development of geothermal energy, especially on the utilization of abandoned oil wells.

Study of Oribatids population on three types of land use at PT Nusantara VIII Plantation, Cisarua Sub-district, Bogor, West Java

Most of the forest area of PT Perkebunan Nusantara VIII have been converted to the plantation (tea, cacao, coffee) and agriculture, such as crops (intercropping of oranges and pineapple) areas. The forest conversion will affect soil biodiversity, which will reduce soil mesofauna population, such as the Oribatids group. Oribatids is one of the soil mesofauna which has a very important role in the soil as a decomposer. Because of its important role and their huge numbers in the soil, Oribatids can be used as a bioindicator of soil fertility. This study aimed to elucidate the abundance and diversity of Oribatids and the relationship between soil properties and population of Oribatids in three types of land use at PT Perkebunan Nusantara VIII. Soil and litter samples were taken in three different types of land use (tea gardens, intercropping, and secondary forests) using a simple random sampling method with a distance of each of the 15 sampling points of 100 m at a soil depth of 0-5 cm. Soil and litter samples were extracted using Berlese Funnel Heat Extractor. Oribatids identification was carried out until the family level, and the Oribatids diversity index were determined according to Shannon's diversity index. The identification results obtained in the three types of land use amounted to 24 families from 172 families found previously. The highest abundance of Oribatids was found in secondary forests both in the soil and litter layer (169.85 and 428.87 individuals/m², respectively), the lowest abundance of Oribatids was found in intercropping both in the soil and litter layer (89.17 and 229.30 individuals/m², respectively). According to Shannon Wiener (H'), the diversity index value ranges from 1.48-1.85 or it was categorized as a low-medium diversity value. The results of this study indicated that there was a positive correlation coefficient value from several families of Oribatids with soil pH, organic C, total N, C/N ratio, water content, and soil temperature.

Diversity of Oribatids (Acari) at different land use types in Mentebah, Kapuas Hulu, West Kalimantan

Kalimantan forests are mostly managed by human. Deforestation will affect the ecosystem and species inside. Oribatids are the most abundant soil mesofauna. They have an important role in decomposition of organic matter in the soil. Here, we investigated the effect of six different land use types (i.e. primary forest, secondary forest, jungle rubber, slash and burn, young fallow and old fallow) and evaluated the effect of environmental factors on the abundance and diversity of oribatids. The oribatids were collected using transect method along 100 m with 10 sampling points with the soil depth of 0-5 cm. Oribatids were extracted using Berlese Funnel Heat Extractor. Identification of oribatids was done to family level and diversity index was determined according to Shannon's diversity index. As much as 36 families of oribatids were recorded from the site at Mentebah, Kapuas Hulu. Oribatids in the jungle rubber showed the highest abundance (592.5 individuals/m 2 ), followed by secondary forest (317.5 individuals/m 2 ), primary forest (287.5 individuals/m 2 ), slash and burn (195 individuals/m 2 ), young fallow (157.5 individuals/m 2 ) and old fallow (142.5 individuals/m 2 ). The value of diversity index according to Shannon Wiener (H’) ranged between 1.71-2.64 or categorized as moderate diversity values. The results of the research showed that there were strong coefficient correlation values of some families of oribatids with soil pH, C-organic, N total, C/N ratio, water content and soil temperature

A new laboratory device with mathematically based positioning of a frozen tissue block facilitating precise sectioning of large specimens.

Mohs micrographic surgery (MMS) is a treatment method aiming at thorough, personalized eradication of skin cancers by mean of staged excision of tissues surrounding the tumor with complete (100%) histopathological examination of their margins. In many MMS laboratories, the excised tissue is divided, shaped, frozen in a cryostat with a heat extractor and positioned manually (with the block on the object disc) in an articulated cryostat chuck during cutting. However, these activities may be difficult, time-consuming and associated with the risk of imprecise tissue sectioning. Development of a laboratory device allowing for processing of large tissue specimens, with the function of mechanical, mathematically steered positioning of the tissue block surface directly to the microtome knife cutting place, eliminating the need for manual adjustment. The prototype device was designed and manufactured. Its functioning was tested on 513 histological slides produced during 212 operations of skin cancers using MMS. The depth of the first complete sections and the diameter of sections were measured. Complete sections were obtained at an average depth of 81.60 m (min. 20 m, max. 180 m, SD = 29.15), whereas the average diameter of sections was 18.11 mm (min. 4 mm, max. 42 mm, SD = 9.10). The histological processing of large specimens with mathematically based positioning of the tissue surface in relation to the cryotome knife cutting plane is precise, fast and easy. The device can be useful in those MMS centers which continue to employ manual setting of the cryostat chuck or share the cryostat with other users, which prevents fixing the chuck position (including large hospital settings). It may also be helpful in centers using a cryostat with a fixed chuck, for the correction of minimal inaccuracies of its preset position.

An experimental and modelling study of a 1 kW organic Rankine cycle unit with mixture working fluid

The ORC (organic Rankine cycle) technology is appropriate for conversion of low-grade industrial waste heat to electrical power due to its utilization of volatile organic fluids as working fluids. It has been proposed that zeotropic fluid mixtures can improve the ORC performance compared to pure fluids. The purpose of this paper was to demonstrate the feasibility of using a zeotropic mixture as working fluid through an experimental study with a lab-scale ORC (organic Rankine cycle) test rig. In this study, a zeotropic mixture of R245fa and R365mfc (48.5%/51.5% on a mole basis) was examined by focusing on its dynamic behavior in the system until reaching steady state and the performance in a scroll expander, a finned-tube heat extractor, an evaporator and a condenser. The test rig used the exhaust gas from a 30 kW Capstone™ Gas Turbine as its heat source. Computer simulation was conducted at system level with steady state conditions and the results were compared to experimental data.

Standardization of ginseng processing for maximizing the phytonutrients of ginseng

This study was designed to optimize the process conditions, such as steaming, drying, and extracting, for obtaining the maximum content of prosapogenin (Rg3, Rg2, Rh1, and Rh2) from red ginseng, which has antitumor and anti-cancer properties. The steaming process was performed in an autoclave and the drying and extracting processes were done in dryer and heat extractor, respectively, and content of each prosapogenin was analyzed by HPLC. In the steaming process, prosapogenin values did not show any significant increase at 80 or 90°C, but tended to increase sharply as the steaming period became longer at 100°C, and the maximum value was obtained at 100°C with 6 h of steaming without any significant difference between local Gyeonggi areas. Drying red ginseng at 70°C for 24 h was the optimal condition to enhance prosapogenin extraction without affecting the quality. Maximal crude saponin and prosapogenin contents were obtained using 70% ethanol as the solvent at 70°C in the extracting process. Using these standardization processes such as steaming, drying, and extraction, maximum prosapogenin values could be obtained at ginseng factories.

Solar hybrid systems with thermoelectric generators

► We examine four hybrid systems with thermoelectric generators (TEGs). ► We studied effect of radiation concentration on the system’s performance. ► Parameters of TEG based on Bi 2 Te 3 were determined and used for analysis. ► TEGs using advanced nanostructured materials were also considered. ► Cost-efficiency estimations and some recommendations for application are made. The possibility of using of thermoelectric generators in solar hybrid systems has been investigated. Four systems were examined, one working without radiation concentration, of the traditional PV/Thermal geometry, but with TEGs between the solar cells and heat extractor, and three other using concentrators, namely: concentrator – TEG − heat extractor, concentrator − PV cell − TEG − heat extractor, and PV cell – concentrator – TEG – heat extractor. The TEGs based on traditional semiconductor material Bi 2 Te 3 and designed for temperature interval of 50–200 °C were studied experimentally. It was found that the TEG’s efficiency has almost linear dependence on the temperature difference Δ T between its plates, reaching 4% at Δ T = 155 °C (hot plate at 200 °C) with 3 W of power generated over the matched load. The temperature dependencies of current and voltage are also linear; accordingly, the power generated has quadratic temperature dependence. The experimental parameters, as well as parameters of two advanced TEGs taken from the literature, were used for estimation of performance of the hybrid systems. The conclusions are drawn in relation to the efficiency at different modes of operation and the cost of hybrid systems, as well as some recommendations in relation to optimal solar cells for applications in these systems.

Catalytic combustion of 1-butanol coupled with heat harvesting for compact power

A combustor paired with a heat-harvesting device, such as a thermoelectric or thermal photovoltaic device, can utilize high energy-dense liquid fuels while avoiding direct chemical-to-electrical conversion issues such as electrode and electrolyte poisoning. Therefore, the system is an attractive alternative to batteries and fuel cells for portable power applications. In the current study, a 1-butanol fed catalytic combustor using a Rh/Al 2O 3 catalyst was tested with a heat extractor, in this case being a stainless steel rod with a copper heat sink that was designed to thermally mimic a small thermoelectric module. The effects of residence time, fuel flow rate, and rod size on reactor/extractor temperatures and the energy balance were observed. Fuel-lean equivalence ratios were also studied and shown to have little effect on performance. Residence time does not have a direct effect; however, it does provide a catalytic stability limit for the fuel flow rate. The difference in the hot and cold side temperatures of the rod is dependent on the fuel flow rate and length of the rod. The greatest difference observed in these temperatures was 513 °C using the long-sized (15 cm) rod. The percentage of fuel energy conducted through the rod is only dependent on the rod size, with a maximum around 40% using the short rod. These results provide important design guidelines for the catalytic combustion of energy-dense liquid fuels as an excellent alternative heat source for either direct use or electrical power conversion.

A Freezing Technique for Base Mold Embedding of Multiple Block Frozen Sections

This article describes a technique for preparing multiple frozen section blocks outside the cryostat chamber. Specimens are first oriented in modified disposable base molds (“platform molds”) in a process similar to paraffin embedding. Freezing takes place in a “CryoCaddy,” which consists of a freezing platform cooled with dry ice and housed in an insulated container. During freezing, the mold is flooded with a tissue fieezing compound, and a chuck is joined to the mold. This establishes a parallel relationship between the chuck, block face, and cutting plane of the cryostat, which ensures that minimal trimming-in is required quired before full-faces ections are obtained. This technique successfully avoids specimen compression and distortion (crush artifact) that may be produced when a weighted heat extractor is used. Furthermore, this technique eliminates ice crystal artifact that occurs when freezing proceeds too slowly. The CryoCaddy has sufficient thermal inertia to allow the preparation of multiple blolcks over several hours, thereby allowing the cryostat to be dedicated to cutting. This fast, simple, and reproducibly accurate technique is ideal for frozen section evaluation of multiple block specimens and/or when precise orientation is required. (The J Histotechnol 30:23, 2007)Submitted May 23, 2006; accepted with revisions November 9, 2006

Mohs Surgery-A New Approach with a Mould and Glass Discs: Review of the Literature and Comparative Study

Mohs surgery is a frozen section-guided surgical excision that is the treatment of choice for aggressive cutaneous malignancy. But it is labour intensive, particularly because numerous levels are needed on each specimen to obtain a complete histologic section. Three different techniques to Mohs surgery are compared. Our new approach with moulds and glass discs is explained and discussed. Review of the literature and comparative study using skin specimens of fresh cadavers. Regional care centre. First, we evaluate, for each of the three different techniques, the number of 10 micron-thick frozen sections required to obtain a macroscopically complete cross section of the specimen. Second, we examine microscopically the quality of these first complete sections. Finally, once we have obtained a macroscopically complete cross section, we evaluate the number of deeper levels required to obtain an adequate microscopic section. In the first experiment, with the modern method, 90.1 sections were needed to obtain a full macroscopic section, 36.8 sections with the heat extractor method, and 10.6 sections with the new mould. The quality of the histologic glass slides was superior with the new mould. The number of deeper levels required to obtain an adequate microscopic section was 5.9 for the modern method, 4.4 for the heat extractor method, and 2.3 for the new approach (new mould). Our new approach with moulds and glass discs is simple and allows us to flatten the specimen (to obtain a complete tissue section) more reliably and efficiently compared with both the modern and the heat extractor methods. The new approach allows us to obtain these results in less time and with fewer histologic glass slides. Some other aspects are discussed.

Mohs Tissue Mapping and Processing

BACKGROUND Mohs micrographic surgery (MMS) is the most reliable, conservative, and tissue-sparing approach to the management of cutaneous malignancies. The concept of MMS is simple, but its technique, which involves a series of suboperations, is complex. OBJECTIVE To define which techniques of Mohs tissue mapping and processing are presently employed by members of the American College of Mohs Micrographic Surgery and Cutaneous Oncology. METHODS Five hundred eighty surveys of eight questions regarding different techniques used in Mohs tissue mapping and processing were mailed out to Mohs micrographic surgeons registered with the American College of Mohs Micrographic Surgery and Cutaneous Oncology. A total of 310 responses (53%) were collected between October and December 2002. The results were tabulated and analyzed. RESULTS Most Mohs micrographic surgeons personally prepare the map of the tissue in relationship to the patient (66.5%). A hand-drawn picture with standard orientations is most frequently used to map and orient a tissue specimen (69.4%). Histotechnicians usually prepare the tissue specimen for cryostat processing (63.5%). A heat extractor and/or tissue cuts or “slits” are the preferred methods used to flatten tissue by 52.9% of respondents. Hematoxylin and eosin is the stain that is most commonly used (82.6%). Approximately 50% of Mohs micrographic surgeons cut the excised specimen from the first stage into two separate pieces. Each tissue piece is then commonly processed into three to six representative serial sections per glass slide (68.1%). These sections are most commonly cut at 5 to 6 μm (53.9%) and less frequently at 4 μm (21.9%). CONCLUSION There is variability in mapping and processing techniques employed Mohs micrographic surgeons and their histotechnicians. As long as the integrity of each step of Mohs tissue mapping and processing is preserved, the high cure rate of the technique should be maintained.

Mohs Tissue Mapping and Processing: A Survey Study

Mohs micrographic surgery (MMS) is the most reliable, conservative, and tissue-sparing approach to the management of cutaneous malignancies. The concept of MMS is simple, but its technique, which involves a series of suboperations, is complex. To define which techniques of Mohs tissue mapping and processing are presently employed by members of the American College of Mohs Micrographic Surgery and Cutaneous Oncology. Five hundred eighty surveys of eight questions regarding different techniques used in Mohs tissue mapping and processing were mailed out to Mohs micrographic surgeons registered with the American College of Mohs Micrographic Surgery and Cutaneous Oncology. A total of 310 responses (53%) were collected between October and December 2002. The results were tabulated and analyzed. Most Mohs micrographic surgeons personally prepare the map of the tissue in relationship to the patient (66.5%). A hand-drawn picture with standard orientations is most frequently used to map and orient a tissue specimen (69.4%). Histotechnicians usually prepare the tissue specimen for cryostat processing (63.5%). A heat extractor and/or tissue cuts or "slits" are the preferred methods used to flatten tissue by 52.9% of respondents. Hematoxylin and eosin is the stain that is most commonly used (82.6%). Approximately 50% of Mohs micrographic surgeons cut the excised specimen from the first stage into two separate pieces. Each tissue piece is then commonly processed into three to six representative serial sections per glass slide (68.1%). These sections are most commonly cut at 5 to 6 microm (53.9%) and less frequently at 4 microm (21.9%). There is variability in mapping and processing techniques employed Mohs micrographic surgeons and their histotechnicians. As long as the integrity of each step of Mohs tissue mapping and processing is preserved, the high cure rate of the technique should be maintained.

Application of heat generated in compost to soil warming.

A simulation model of a soil warming system with a compost heat extractor was proposed. The soil warming system for the model simulation was constituted by some compost beds for heat extraction, pipe lines for circulation of the medium water and water reservoirs. The application of the simulation model to the practical example for warming the soil bed was investigated by the analysis of the heat balance of the system, using some actual operating conditions. The heat balance in the soil warming was treated analytically and systematically, taking account of the process control of the system. The concept of the model simulation and procedure for the systematical analysis of the heat balance in the soil warming may be of use for the planning, design and operations of the actual soil warming system.