High Water Flow Rates Research Articles

Thermochemical heat storage and material behavior of calcium hydroxide fine powder in a fluidized bed reactor

The Ca(OH)2/CaO reaction has attracted much attention in thermochemical heat storage. However, commercial Ca(OH)2 is usually offered as a fine powder that tends to agglomerate in the fluidized bed and affects heat storage performance. The experimental study on these issues is incomplete. In this paper, a fluidized bed thermochemical heat storage test system is built to study the heat storage and release process of Ca(OH)2 fine powder. The experimental results indicate that the water vapor is the primary factor in agglomeration. The increase in heat storage temperature, fluidization velocity, and inlet water flow rate can all reduce reaction time. However, the effect of heat storage temperature on agglomeration is negligible. While a high fluidization velocity can alleviate the agglomeration, a high inlet water flow rate intensifies the agglomeration. The heat storage density decreases by about 12 % after 5 cycles owing to the material loss, while the agglomeration is trending upward. The specific surface area and specific pore volume decrease by 46.59 %, and 13.89 % respectively, which slows down the heat storage process. This work can serve as a reference for alleviating the agglomeration, as well as the operation and adjustment of the fluidized bed.

KATANA - water activation facility at JSI TRIGA, Part II: First experiments

Water as a primary coolant will play an important role in the performance of fusion reactors, as after being irradiated and activated, it causes an ionising radiation field throughout the facility. In direct support of ITER, the KATANA irradiation facility, which utilises a closed-water activation loop and serves as a well-defined and stable high-energy γ and neutron source, was commissioned in 2024 at the TRIGA Mark II research reactor at the Jožef Stefan Institute in Slovenia.A series of first experiments using the KATANA irradiation facility were performed to determine the operational characteristics of the KATANA, i.e. characterisation of the neutron flux within the irradiation component, dose rate measurements, spectrum characterisation of the activated water, and response to a change in reactor power & flow rate. The KATANA facility demonstrated the desired operational characteristics in terms of high and stable water flow rates and high activity values of the observed isotopes 16N, 17N and 19O, which is essential for minimising the experimental uncertainties.The first experiments performed at KATANA provided in-depth knowledge into the operation and capabilities of the facility and essential data to serve as a basis for further, more detailed/benchmark experiments.

KATANA - water activation facility at JSI TRIGA, Part I: Final design and activity calculations

Water as a primary coolant will play an important role in the performance of fusion reactors, as it causes an ionising radiation field throughout the facility after its irradiation and activation and requires improved shielding for instruments and personnel. To support ITER, the KATANA irradiation facility, which utilises a closed-water activation loop, was built, licenced and commissioned in early 2024 at the TRIGA research reactor at the Jožef Stefan Institute in Slovenia.A comprehensive overview of the KATANA irradiation facility, which serves as a well-defined and stable high-energy γ and neutron source, is given, including the final design, experimental set-up, detector systems and overall timeline. The physical characteristics of KATANA were assessed by analyses of neutron transport simulations leading to activity calculations in connection with a conventional analytical approach, without using CFD calculations. The KATANA facility demonstrated the desired operational characteristics in terms of high and stable water flow rates, leading to high activity values of the observed isotopes 16N, 17N and 19O, which is essential for minimising experimental uncertainties.The preliminary calculations provided in-depth operational knowledge and important data for the KATANA facility, forming a basis for more advanced future experiments.

A Wearable Extracorporeal CO2 Removal System with a Closed-Loop Feedback.

Extracorporeal Carbon Dioxide Removal (ECCO2R) systems support patients with severe respiratory failure. Concurrent ambulation and physical therapy improve patient outcomes, but these procedures are limited by the complexity and size of the extracorporeal systems and rapid changes in patient metabolism and the acid-base balance. Here, we present the first prototype of a wearable ECCO2R system capable of adjusting to a patient's changing metabolic needs. Exhaust gas CO2 (EGCO2) partial pressure is used as an analog for blood CO2 partial pressure (pCO2). Twin blowers modulate sweep gas through the AL to achieve a desired target EGCO2. The integrated system was tested in vitro for 24 h with water, under varying simulated metabolic conditions and target EGCO2 values, and in a single test with whole blood. When challenged with changing inlet water pCO2 levels in in vitro tests, the system adjusted the sweep gas to achieve target EGCO2 within 1 min. Control runs with a fixed sweep gas (without negative feedback) demonstrated higher EGCO2 levels when challenged with higher water flow rates. A single in vitro test with whole ovine blood confirmed functionality in blood. This is the first step toward wearable ECCO2R systems that automatically respond to changing metabolism. Such devices would facilitate physical therapy and grant greater autonomy to patients.

Development of an Ultrasonic Nebulization System for an Inverse Low Temperature Plasma Ionization Source.

An effective nebulization and evaporation of a liquid sample, like in liquid chromatography, mass spectrometry (LC-MS) couplings, is an essential requirement for the ionization of analyte molecules in the gas phase by, for example, atmospheric pressure chemical ionization (APCI) or the novel low temperature plasma (LTP)-based ion source. These LTP-based ion sources have recently gained interest in the field of atmospheric pressure ion sources, as they can cover a wide range of polarity and molecular mass. They can be used in combination with separation techniques like liquid chromatography or used as an ambient ion source. However, commercial nebulizer systems are of course not constructed to fit to home-built LTP-based ion sources, and this was one incentive to develop a new nebulization system. Instead of an atmospheric pressure chemical ionization (APCI) nebulizer, two commercial nebulizers were disassembled and remodeled to be used as nebulizing systems in an LC-MS setup using an LTP-based ion source. Based on these results, a novel nebulizer system was subsequently developed. To further improve the degree of ionization, cones to focus the LC eluent spray on the plasma region, heating applications, and auxiliary nitrogen gas for dispersion of the solvent droplets were implemented. The LOD that could be calculated via the rule of three resulted in an average of 2.0 μg/L for the APCI-nebulizer and 41 μg/L for the USN. Both could be reduced to 1.4 and 18 μg/L, respectively, by using a TPI-configuration instead of an iLTP. The linearity was equally good for both types of nebulization devices. The final nebulizer could also be operated with a high water content and flow rates higher than those of the two previous ones, indicating an important improvement step.

Evaluation of formation damage and filter cake removal with a new LPM drilling fluid additive

This study evaluates the LPM-FBR drilling fluid additive's performance in minimizing formation damage and facilitating filter cake removal in fractured and high-permeability cores. Using a Formation Damage System Apparatus, two experimental studies were conducted to address the challenge of balancing fluid loss control and formation damage mitigation in fractured reservoirs. The first study, comparing a base saltwater mud with and without LPM-FBR on a 1231 mD fractured sandstone core, showed that LPM-FBR significantly enhanced fluid loss control. It withstood 552 psi overbalance pressure with minimal fluid loss (85.6 mL over 6 h), effectively sealing fractures. However, it reduced return permeability from 1500 to 47.8 mD. The second study, using a 2000 mD fractured core, demonstrated LPM-FBR's effectiveness in limiting filtrate invasion to 5.7 mL over 4 h at 600 psi overbalance. Subsequent cleaning with caustic soda proved ineffective, severely impairing return permeability to 19–28 mD. A breaker solution with a high flow rate of water flushing showed more promise in filter cake removal. This research highlights the trade-offs between fluid loss control and formation damage when using LPM-FBR muds. While excelling in minimizing fluid losses under high overbalance conditions, the additive poses challenges in post-drilling permeability restoration. These findings underscore the need for comprehensive removal procedures to mitigate long-term productivity impairment in fractured reservoirs, contributing valuable insights for optimizing drilling fluid design and post-drilling cleanup strategies.

Flow pattern and pressure drop analysis of two-phase segmented flow driven by a thermomagnetic pump

The two-phase segmented flow is a flow pattern in which two immiscible fluids alternate in a flow channel with distinct segments. In this study, a thermomagnetic pump operated by heat and an external magnetic field was used to drive the flow and the temperature-sensitive magnetic fluid (TSMF) was chosen as the continuous-phase fluid to generate a two-phase segmented flow. The dispersed-phase fluid was selected as air or deionized water driven by a syringe pump. The two-phase segmented flow experiments were conducted to investigate the relation between segment length and the dispersed-continuous phase flow rate ratio at the air flow rate from 0.90 ml/h to 4.49 ml/h for air-TSMF experiment and water flow rate from 0.36 ml/h to 0.72 ml/h for water-TSMF experiment. The ratio was proportional to the bubble/droplet length and inversely proportional to the slug length. The air/water length per channel width can be up to 3.28 and 1.79, respectively, at the highest air/water flow rate in the current experiment. Moreover, the pressure drop was measured to increase with the dispersed-continuous phase flow rate ratio. The maximum pressure drop was observed as 428.2 Pa in the water-TSMF experiment with the highest water flow rate and the maximum pressure drop was 314.7 Pa for the air-TSMF experiment. These findings provide valuable insights for controlling the segment length in the two-phase segmented flow driven by a thermomagnetic pump and it could be used as precise control of liquid/gas fuel delivery in a micro-propulsion system in small satellites.

Monitoring of microplastic pollution in sediments along the Çoruh River Basin, NE Türkiye

Microplastic (MP) pollution has become a research issue on the world agenda. Monitoring studies are essential for MP content in aquatic environments since it is the final accumulation point. The present study focused on MP characterizations in sediment samples taken from 20 different stations on the Çoruh River, the major river in the North East of Türkiye. Accordingly, the potential anthropogenic pollution from settlements near the four stations (2, 15, 18, and 20) exceeding 400 MP kg−1 was estimated. On the other hand, stations (1, 3, 9, 11, and 13) far from settlements with quite low MP abundance were also observed. The polymer structures of the detected MPs are generally PE and PET, and their shapes are mostly fiber. This situation raises suspicion that MPs originate from primary use waste such as water bottles and packaging materials. In general, the fiber MPs are smaller than the fragments because of the river's high water flow rate and the low strength of the fiber MPs. In light of these results, the current monitoring data in the region will create awareness and guidance regarding MP pollution in settlements.

Effect of Cross-Sectional Depth on Horizontal and 30° Slop Spillway Open Channel Pico Hydro Cross-Flow Turbine Efficiency

Harvesting the kinetic energy from the small dam’s spillway downstream flow in agricultural areas is interesting. On the other hand, a cross-flow turbine (CFT) is a unique impulse turbine because it works at a higher specific speed, which means this turbine works at a lower head and higher water flow rate. Thus, there is an opportunity to use a CFT to harvest the energy in the spillway. There are two possible scenarios: at the flat horizontal and the 30° slop flow. Several computational fluid dynamics (CFD) simulations were conducted to test the hypothesis. The simulations were performed with five variations of the ratio between the cross-sectional depth parameter of the spillway’s flow before approaching the turbine for each scenario. The total head in the present study case is 3.0 meters with 120 l/s of water discharge. The simulations used ANSYS® Fluent™ for 2D CFD simulation. The tests found that the CFT could attain 80.36% efficiency. Moreover, some water flows over the turbine at a higher rotational speed, leading to a significant loss in turbine performance, called potential loss. This finding indicates that the CFT could harvest the spillway’s flow kinetic energy when the flow is not too deep.

Experimental study on flow characteristics in a new separator

The confined multiphase swirling flow characteristics were studied in the presence of a new bluff body for gas/liquid separation. It is a hollow cylinder with a tapered front. The flow visualization was performed using High Speed Camera. The gas-to-liquid ratio was controlled by manipulating the air and water flow rates in the flow loop. Based on previous studies, the generated air core exhibits different regimes with stable and unstable regions along the pipe axis. The proposed bluff body should be placed with the stable region to avoid the loss of separation efficiency due to the oscillations of the air core. Three flow regimes were considered based on the water flow rate. At the low water flow rate, the air core is thinner and breaks down a few centimeters upstream of the bluff body. The generated bubbles are sucked inside the bluff body. Increasing the air flow rates causes the air core to get closer to the bluff body until reaching it completely and might enlarge exceeding the bluff body diameter. For all the cases considered, the air core is wavy with highly instable diameter and length. When increasing the water flow rate, a more stable air core is formed closer to the bluff body. The high-water flow rate appears to be necessary to stabilize the air core and reach flow regimes favorable for an efficient separation through both the annular space and the internal passage.

ANALISIS ALIRAN PADA BUCKET TURBIN PELTON 1 KW DENGAN VARIASI SPEAR NOZZLE MENGGUNAKAN METODE CFD

Pelton turbine have been used for harvesting renewable energy by extracting kineticenergy of water into mechanical energy for more than 100 years. This characteristic makes thissystem remains potential to achieve Goals #12 SDGs. During the operation, the performance ofPelton Turbine is affected by several parameters: hydraulic power, water flow rate, bucketdesign, and nozzle. Among others, nozzle design is the most challenging since this part isresponsible to drive the water direction strike the buckets, converting impulse. The performanceof existing 1 kW Pelton Turbine equipped with 15mm Spear Nozzle is believed can be improvedby varying the nozzle diameter by using low-cost CFD simulation procedure. Ansys Fluent fromAnsys Student 2021 R1 is used in this research. Represented by two-buckets facing spear nozzle,three dimensional CFD simulation is conducted. The nozzle diameter is varied to 15 mm, 14 mm,and 13 mm from two configurations. The first and second configuration is done with water flowrate 3,3 kg/s and 1,3 kg/s respectively. The results show that 15 mm nozzle diameter can producehigher power as high as 594,08 Watt with the first configuration. Even though at the secondconfiguration this 15mm nozzle diameter did not produce the highest power, other parameterssuch as splashing water and erosion effect still show that the 15mm nozzle diameter performedbetter than others. This simulation results also consistent with experimental results whichperformed by using first configuration and 15mm nozzle diameter. The results also show that thesistem performance is much higher at higher water flow rates. Therefore, the development of thesystem can be continued to by using spear nozzle with diameter higher than 15mm.

Experimental performance and economic analysis of finned solar receiver for parabolic dish solar collector

The solar receiver is a vital component of concentrated solar collectors that absorbs solar radiation and converts it into heat. One of the challenges the research community faces is minimizing heat loss from the receiver at higher temperatures to maximize the thermal performance of parabolic dish collectors and achieve the system's cost-effectiveness. Cavity receivers have a complex design that makes them more challenging to manufacture and entails higher costs for improved thermal performance. Implementing innovative receiver designs is essential to maximize the absorption of solar radiation and minimize heat losses. In this experimental study, a cost-effective solar receiver was fabricated with fins to study heat transfer. The solar receiver is examined using water as heat transfer fluid with three flow rates of 0.097 kg/s, 0.125 kg/s, and 0.152 kg/s. The residence time of water is increased by adopting integrated fin receiver designs. The provision of fins in the solar receiver enhances heat transfer by increasing the turbulence in the fluid flow and results in higher thermal efficiency. The average energy and exergy efficiencies are 67.81 % and 8.93 %, respectively, with a 0.152 kg/s flow rate. At the highest water flow rate (0.152 kg/s) considered in this study, a lesser heat loss of about 3776.2 W occurred due to the effective heat transfer. The cost metrics, like levelized cost of electricity, net present value, and the payback period, are about 0.21 $/kWh, 923 $, and 3.38 years, respectively, at 0.152 kg/s flow rate. The proposed solar receiver produces optimal thermo-economic performance and lower initial investment for steam generation than other receiver designs. The current experimental study's findings could benefit the entire solar industry by presenting an effective solar receiver design for solar collectors.

Seasonal and environmental dynamics of intra-urban freshwater habitats and their influence on the abundance of Bulinus snail host of Schistosoma haematobium in the Tiko endemic focus, Mount Cameroon region.

Urogenital schistosomiasis (UGS) caused by Schistosoma haematobium is endemic in the South West Region of Cameroon. An understanding of the abundance and distribution of the Bulinus snail, intermediate host can inform strategic snail control programmes at a local scale. This study investigated seasonal dynamics and environmental factors influencing occurrence and abundance of freshwater snail intermediate hosts in Tiko, a semi-urban endemic focus in the Mount Cameroon area. A longitudinal malacological field survey was conducted between December 2019 and December 2020 in the Tiko municipality. Snails were collected for one year monthly at 12 different human water contact sites along a stretch of the Ndongo stream using a standardized sampling technique. Freshwater snails were identified using shell morphological features. In addition, water temperature, pH, electrical conductivity, total dissolved solutes, salinity, water depth, width and flow velocity were measured, and vegetation cover as well as substrate type were determined. Bayesian regression models were used to identify the main environmental factors affecting the occurrence and abundance of Bulinus intermediate host. In total, 2129 fresh water snails were collected during the study period. Physa (51.4%) was the most abundant genus followed by Melanoides (28.6%) then, Bulinus (15.5%), Lymnaea (4.2%), Indoplanorbis (0.2%) and Potadoma (0.1%). Seasonality in abundance was significant in Bulinus sp as well as other genera, with greater numbers in the dry season (peaks between December and February). Water temperature, a rocky or sandy substrate type associated positively with Bulinus sp, meanwhile a higher water flow rate and medium vegetation negatively influenced the snail intermediate host population. These findings underscore the importance of timing behavioural and snail control interventions against schistosomiasis as well as increase vigilance of other trematode diseases in the study area. The continuous spread of planorbid snail hosts is a major concern.

Design and modular scale-up of shell and tube metal hydride hydrogen storage reactor utilizing multi-pass water flow

Shell-and-tube designs with multi-pass fluid flow are not used for metal hydride hydrogen storage reactors. Here, the absorption performances of reactors having shell outer diameter [OD]: 114.3, 141.3 and 168.3 mm with 36, 60 and 92 tubes arranged in 3, 4 and 5 circular arrays housing 25 kg LaNi5 at 20 bar hydrogen pressure, 10 LPM water entering at 30 °C are simulated. Considering the trade-off between tube volume and reaction duration, OD: 141.3 mm, 60 tubes offers a balanced performance with 90% absorption taking ∼320 s with four water passes (4-pass-scheme) vis-à-vis ∼380 s with one pass (1-pass-scheme). This design is scaled-up to house 100 kg LaNi5 with four modules in series and parallel configurations. When in series, reactors take 320, 425, 545, and 665 s for 90% absorption; in parallel, each reactor takes 625 s. At higher water flow rate (40 LPM) series and parallel configurations perform similarly.

Electrospray mass spectrometry method to prevent the reduction of hexavalent to pentavalent chromium

RationaleElectrospray mass spectrometry (ESI‐MS) is one of the most effective methods for assessing the state of metals in solution. For ions with a redox potential close to ~0.55 V, such as Cr6+, reduction of the metal in solution occurs in the ESI‐MS system. In our studies, it was observed that [HCrO4]− undergoes reduction, resulting in the formation of [CrO3]−. The precise mechanism remains ambiguous. The reduction of hexavalent chromium to pentavalent chromium is supported by Frost diagrams, reinforcing our confidence in the validity of the ESI‐MS measurement method. The reduction mechanism in ESI‐MS was clarified, and a system was devised to eliminate electron donation during the reduction of Cr6+ in solution.MethodsTo determine the state of Cr6+ by ESI‐MS, CrO3 in solid form was dissolved in ultrapure water to prepare a solution of 500 × 10−6 mol/L (μM) concentration. The pH was adjusted to 4.0, 5.3, 6.3, 8.2 and 9.1 and subsequently measured. CrO3 solutions with various concentrations of 10, 100 and 500 μM were prepared and adjusted to a pH of ~7 using tetramethylammonium hydroxide to measure Cr6+ under different conditions.ResultsCr6+ in solution was soluble and existed as an oxoacid with a negative charge independent of pH. Cr6+ was stable over a wide pH range at various concentrations. The ESI‐MS method determined the negative ion [HCrO4]− as the stable ion, but [CrO3]− was also present as a byproduct. Therefore, we were interested in the presence of other species, such as [CrO3]−, which could have formed owing to the reduction of Cr6+.ConclusionsIn ESI‐MS system, it undergoes reduction to form [CrO3]−. The high flow rate of ultrapure water in pump insulated the acceptance of electrons by Cr6+ preventing its reduction. Further in‐depth ESI‐MS studies could explain the complex formation and behavior of Cr6+ in aqueous solution.

Hydrodynamics of Supersonic Steam Jets Injected into Cross-Flowing Water

High-speed gas/vapour jets injected into a cross-moving sonic liquid signifies a vital phenomenon which bears useful applications in environmental and energy processes. In the present experimental study, a pulsating jet of supersonic steam was injected into cross-flowing water. Circulation zones of opposite vorticity owing to the interaction between the steam jet and cross-water flow were found. However, a large circulation appeared in front of the nozzle exit. Also, most small circulation regions were observed at higher water-flow rates (>2 m3/s). Among the prime mixing variables (i.e., turbulence kinetic energy (TKE) and Reynolds shear stress (RSS)), the RSS estimations backed a small diffusive phenomenon within a region far from the nozzle exit. Further information extracted from the PIV images indicated the existence of Kelvin–Helmholtz (KH) instabilities. The counter-rotating vortex pairs (CVPs) appeared to be significant in the region close to the nozzle exit, and they exhibited leeward side folds. Moreover, the effects of the operating conditions on the pressure recovery and mixing efficiency as well as the penetration and the separation height were evaluated to determine the optimisation of the phenomenon. By applying extreme difference analysis, the mixing efficiency was found as the most influential parameter.

Design and analysis of cooling jacket developed for vacuum power tubes by multiphase cooling

The vacuum tubes are used extensively in electronic industries. The MW level of vacuum tube are used in RF amplifiers and microwave sources in different sectors like defence, nuclear energy, satellites and medical diagnostics. The first step in the indigenous development of MW level of vacuum tube is the design of its cooling jacket. The cooling jacket of vacuum tubes use hypervapotron (HV) fins which are known for providing efficient cooling in compact space. The key objectives of this paper are to finalize the jacket’s construction material, evaluate the cooling jacket’s heat transfer performance at the MW level of RF (radiofrequency) power, and forecast safe operating conditions for given conditions of high heat flux and water flow rates. In this design, the vacuum tubes’ external dimensions are taken into consideration when designing the cooling jacket. ETP copper (Electrolytic Tough Pitch copper) and copper-chromium-zirconium (CuCrZr) are likely materials for the jacket’s construction. For the aforementioned design of the cooling jacket, FEA (Finite Element Analysis) simulations using a steady-state thermal module and computational fluid dynamics (CFD) simulations using an ANSYS CFX module are described for flow rates of 15, 30, and 60 lpm (liters per minute) and the heat flux 1, 2, 4, and 6 MW m−2. The results of CFD and FEA simulations are found to be in close agreement. A small deviation in results is seen after the start of nucleate boiling. 30 and 60 lpm are desirable flow rates for high heat flux values greater than 2 MW m−2. CuCrZr is the ideal material for a cooling jacket’s construction as it has safe working temperature limit of 350 °C at high heat flux values. Also, 15 lpm flow rate should be avoided while using this cooling jacket at heat flux values greater than or equal to 6 MW m−2.

Состояние экосистемы озера Хедо (западная Карелия) в условиях рыбоводной деятельности

The article highlights the analyzes of the ecosystem of Lake Khedo (Republic of Karelia) under conditions of growing anthropogenic load caused by using the lake for breeding trout in fish cages based on the proper and literature data. Comparative analysis of hydrochemical data before the operation of the farm (until 2005) and after showed a twofold increase in water color (70-150°), which indicates an increased content of organic pollutants (humus, peat, silt). Also in the reservoir there are increased nitrogen and phosphorus compounds. Previously, the concentration of total phosphorus did not exceed 0.01 mg/l, today it reaches 0.02 mg/l. The main factor contributing to the satisfactory state of Lake Khedo is the high water flow rate, due to which most biogens are flown outside the lake. The data on the main hydrobiological indicators of the lake (phytozooplankton and zoobenthos) are presented. It has been stated that if earlier the reservoir corresponded to the mesohumous oligotrophic type, at present it reaches the initial level of mesotrophy, which is probably facilitated by the long-term cage cultivation of the aquaculture object. In terms of the abundance of organisms of the initial trophic levels, the reservoir corresponds to α-mesotrophic type. The lake is inhabited by 8 species of fish, and the valuable ones include whitefish Coregonus lavaretus (L.) and vendace Coregonus albula (L.). The results of the research made it possible to clarify the total production of commercial trout, which amounted to 300 tons per year and doesn’t exceed the total biogenic load. Recommendations on timing the regular ecological expertise of the lake and the adjustment of production volumes are given

Experimental study on a moisture-conducting fiber-assisted tubular indirect evaporative cooler

Indirect evaporative cooling (IEC) is sustainable and energy-efficient for air cooling. The tubular indirect evaporative cooler (TIEC) is widely used because of its stable and efficient cooling efficiency. However, the conventional TIEC has problems such as poor wetting performance of the wet channel surface and high spray water flow rate. Therefore, this study proposes a novel TIEC based on moisture-conducting fiber to improve the distribution of water film outside the tube by taking the advantage of the characteristics of moisture-conducting fiber. Firstly, the moisture conductivity of different fiber materials is tested to select the moisture-conducting fiber for TIEC. Secondly, the performance of TIEC based on moisture-conducting fiber is experimentally investigated under various working conditions and configurations to obtain the TIEC configuration scheme with a relatively optimal performance. The results show that Coolmax moisture-conductive fiber is the best selection for TIEC applications because of its excellent ability to induce moisture transport and diffusion. The overall performance of the configuration scheme of TIEC based on moisture-conducting fiber supplemented with intermittent spraying strategy is relatively optimal. The proposed moisture-conducting fiber-assisted TIEC is able to enhance water migration and diffusion, thus improving the wetting performance, saving water and enhancing the cooling efficiency.

(129) A Neurological Excitation/Inhibition “Faucet Model” for Orgasm and Pain

Abstract Introduction A prevalent concept of neuronal inhibition in sexual response is that it opposes the effects of neuronal excitation, e.g., the classical arm balance in which excitation and inhibition are on opposite arms of the balance; when one is up, the other is down (Perelman: Curr Sex Health Rep 2018;10:38). However, there is extensive evidence that neuronal inhibition can increase jointly and concurrently with neuronal excitation. Objective To review extensive evidence of neuronal inhibition increasing concurrently with neuronal excitation in various contexts including sexual response and orgasm. Methods Review neurological evidence and propose a novel model of neuronal excitation and inhibition acting jointly to enable intense sexual response and orgasm. Results The intensity of neuronal inhibition can increase concurrently with an increase in excitation, thereby actually enabling the excitation intensity to increase, as in the most basic functions of the nervous system, i.e., the spinal reflexes, and in graceful, non-spastic movement of precision, and intense movement. Sensorially, pain activates the endogenous pain-inhibiting system. In sexual response, as the intensity of response to vaginal self-stimulation increased from pressure to pleasure to orgasm, the intensity of pain inhibition also increased. The spinothalamic tract, which transmits pain, also transmits the genital stimulation leading to orgasm. In the brain, major components that are activated by pain are also activated by orgasm, evidence of sites of inhibitory interactions between genital afferent activity and pain perception. When the intensity of excitation surpasses that of concurrent inhibition, the excitation is perceived as aversive or painful (Komisaruk & delCerro: Sex Med Rev 2022;10:481). We propose a model of this view of concurrent excitation and inhibition, both increasing in intensity jointly to orgasm, as hot (excitatory) and cold (inhibitory) water flowing from a faucet. This model differs from that of a classical balance in that it incorporates variations in intensity of excitation and inhibition independently of each other as well as concurrently and jointly, rather than just reciprocally. Thus, a low versus high flow rate of hot water would represent mild or intense pain, whereas a high flow rate of both hot and cold water would represent intense, but non-painful, comfortable excitation, as in orgasm, with perhaps the hot water intensity just exceeding the cold at orgasm. Weak, “anhedonic” orgasm, or premature ejaculation are represented by the “faucet model” as hot and cold water at a very low flow rate; anorgasmia and/or “HSDD” as cold consistently surpassing hot at any flow rate, from low to high, depending on the dynamic qualities of the anorgasmia, i.e., not “getting going”, or “getting close, but not there”, with regard to orgasm. In the latter case e.g., a titrated combination of excitatory (hot) and inhibitory (cold) pharmaceuticals might enable a more delayed and intense orgasm. Conclusions Our proposed “faucet model” of neuronal excitation and inhibition mediating sexual response and orgasm, which is based on extensive neurological evidence, we believe can account for a variety of healthy and pathological sexual responses, and provide a rational basis for therapeutic application. Disclosure Any of the authors act as a consultant, employee or shareholder of an industry for: Adamo Bioscience (first author); many others (last author).