Average Burn Research Articles

Combustion Characteristics and Performance of Nanoflower Structure AlB2@AP Energetic Composites

ABSTRACT Boron-based solids have garnered significant attention due to their high calorific value. However, during combustion, the formation of boron oxide (B₂O₃) on the surface hinders the interaction between the oxidizing components and the internal active boron (B), thereby limiting its reactivity and combustion efficiency. Modifying boron-based solids represents an effective strategy for overcoming the limitations associated with fuel energy release efficiency. In this study, a shell-structured AlB₂@AP composite was designed and fabricated utilizing etching and recrystallization methods. The structure comprises AlB₂ as the core, B as the middle shell, and AP as the embedded outer shell. The key strategy involves employing an etching process to augment the reactive surface area of boron on the aluminum diboride surface, while also coating it with ammonium perchlorate (AP) to enhance the composite particles. This innovative approach demonstrates that the etching method can effectively utilize the boron present in AlB₂. The composite particles were characterized and analyzed for morphology employing a scanning electron microscope and X-ray techniques. Thermal analysis indicated that the decomposition stage of AP facilitated the oxidation of etched AlB₂, moreover, as the AP coating content increased, the temperature at which vigorous reactions initiated occurred earlier. In combustion experiments, the maximum combustion temperatures of AlB₂@10AP, AlB₂@20AP, and AlB₂@30AP increased by 36.4%, 15.1%, and 3.8%, respectively. The combustion formulation prepared with elemental boron exhibited different characteristics. The average combustion temperatures increased by 33.1%, 23.4%, and 14.4%, respectively. The combustion durations were reduced by 60.8%, 33.7%, and 31.7%, respectively. AlB2@AP is anticipated to further enhance its applications in propellants, explosives, and pyrotechnics.

Study on combustion characteristics of ammonium perchlorate enhanced hydroxylamine nitrate-based electronically controlled solid propellant

Electrically controlled solid propellants (ECSPs) have attracted significant attention as a novel class of solid propellants owing to their unique electrochemical properties. In this study, a series of ECSP formulations composed of hydroxylammonium nitrate (HAN), ammonium perchlorate (AP), and polyvinyl alcohol (PVA) were prepared and experimentally investigated to understand the effect of applied voltage on their combustion characteristics, and their combustion behavior was systematically characterized. The results demonstrated that the addition of AP decreased the initial conductivity of the ECSP; however, the average combustion rate during steady-state burning increased significantly, along with a corresponding increase in the combustion temperature. This effect became more pronounced with increasing AP concentration. The dissolved AP in the system acts as an efficient charge carrier, whereas the undissolved AP enhances the combustion performance by producing oxygen through thermal decomposition. Furthermore, even under atmospheric pressure conditions, the combustion of the ECSP can be effectively controlled by adjusting the applied voltage, with combustion ceasing upon removal of the voltage. The mechanism by which AP enhances combustion was analyzed, providing new insights for the optimization of ECSP formulations.

Spent tea leaves and tea bags - promising biofuels?

The spent tea leaves used after the extraction of liquid from processed tea are insufficiently utilized waste, rich in essential amino acids, polyphenols, alkaloids, and minerals, produced in large quantities, e.g., in tea houses, hospitals, school canteens, etc. Therefore, this study is aimed at characterizing this waste, how it is processed into pellets and how it subsequently increases its energy potential by torrefaction. The influence of the method of tea packaging, i.e., loose tea leaves or tea bags, was also considered. Several types of tea waste were processed using a pilot plant pelletizing press and torrefaction stand. The prepared pellets were characterized by mechanical parameters, such as the pellet durability index, the wettability index, water resistance, hardness, or specific bulk density, and were integrated by FTIR measurements. Furthermore, pellet’s energy parameters, such as higher heating value, lower heating value, and elemental analysis, were compared. The results show that non-torrefied pellets have an average combustion heat of 19 KJ.kg-1, while torrefied pellets have a value of 9 KJ.kg-1 higher. Overall, the study demonstrates that spent tea leaves can be converted into a sustainable source of bioenergy and presents a solution for the treatment of this waste, as well as a renewable energy option.

High Resolution (30 m) Burned Area Product Improves the Ability for Carbon Emission Estimation in Africa

AbstractFire significantly contributes to greenhouse gas emissions. The current global burned area (BA) products mainly have coarse native spatial resolution, which leads to underestimation of global BA and carbon emissions from biomass burning. Performances of BA products in Africa from GABAM (30 m), MCD64A1 (500 m), GFED4s (0.25°), FireCCI51 (250 m), and GFED5 (0.25°) were compared. From 2014 to 2020, GFED5 detected the most BA, 1.58 times more than GABAM during the same period. GABAM detected 0.09 Mkm2 more burned area than FireCCI51 on average. From 2014 to 2016, GABAM detected an average of 2.99 Mkm2 of BA in Africa, which was 1.03 times more than GFED4s. From 2014 to 2021, the average African BA derived from GABAM was 2.89 Mkm2, 1.22 times more than MCD64A1. The increase in BA will inevitably lead to an increase in the estimation of carbon emissions from biomass burning. Based on GABAM products and GFED framework, we estimated the average vegetation burning carbon emissions in Africa from 2014 to 2021 to be 1113.25 Tg, which is higher than GFED4s' carbon emissions in the same time period. This shows that the use of high‐resolution (30 m) burned area products to estimate carbon emissions can effectively avoid the underestimation of overall fire carbon emissions.

Thermal analysis of St. John's Wort wastes and biochars: A study of combustion characteristics and kinetics

St. John's wort, extensively utilized in industries such as food, medicine, and cosmetics, generates substantial biomass waste. Utilizing these wastes is crucial to reducing environmental harm and making an economic contribution. This study aimed to determine the potential of St. John's wort wastes and biochar forms produced from these wastes to be used as solid fuel. In this context, the combustion behavior of the biomass and biochar were determined by thermogravimetric analysis method. Additionally, the Kissenger-Akahira-Sunosa and Flynn-Wall-Ozawa techniques were used to compute the combustion activation energies of these samples. According to the analysis, biomass combustion commenced at approximately 250°C and occurred in two stages, whereas biochar combustion initiated at around 400°C and proceeded in a single stage. Furthermore, over 90% of the mass from both samples was observed to decompose during combustion, with average combustion activation energies ranging between 70.08 and 203.86 kJ/mol for biomass and biochar, respectively. These findings suggest that biomass exhibits more readily combustible characteristics compared to biochar but is less energy efficient. In conclusion, optimizing the biochar production process could enhance its energy efficiency and potentially narrow the performance gap between biomass and biochar. Additionally, further research into alternative methods or additives to improve the energy efficiency of biomass combustion is warranted.

Temporal variations in burn severity among various vegetation layers in subtropical Pinus Roxburghii (Chir Pine) forest of Hindu Kush mountain range

The Sub-tropical forests of Pinus roxburghii (chir pine) provide various ecosystem services and act as watershed for low lying regions. However, this species is prone to human induced fire primarily due to local communities' dependence for various resources exacerbated by the current dry conditions. The impact of fire across various vegetation layers and developmental stages has not been thoroughly studied. Bearing to this, the present study was conducted using composite burn index to assess the severity on various layers of vegetation and their long-term impact through a chronological approach. The impact of fire on 40 representative circular plots with a radius of 30 m, categorized into five forest strata: large and intermediate trees, seedlings/saplings, pole stage, shrubs, and soil were investigated and compared across four different time interval: unburnt (B0), burnt two years ago (B2), burnt five years ago (B5), and burnt 15 years ago (B15). The results were statistically proved using Kruskal–Wallis followed by Dunn's Post Hoc and Friedman test with the Holm correction in R Language. The study revealed significant variations in the average burn severity for each treatment, with shrubs having the highest average score of burn severity (average = 1.4) and soil showing the lowest (average = 0.408). The results of the Friedman test indicated non-uniform distribution of burn severity across different ecological treatments. This study is contributing significant insights into the effects of forest fires and their severity on different vegetation layers, which can be instrumental in devising and executing successful restoration strategies.

A high-precision and near-zero residue laser-controlled gel propellant

Micro-nano satellites, with their advantages of small size, low power consumption, short development cycles, and capability for formation flying and networking, play a significant role in scientific research, national defense, and commercial applications. However, currently developed micro-nano satellites globally possess very limited maneuverability and lack effective attitude and orbit propulsion control. Solid propellants can offer some advantages such as high energy density and low cost, and they are extensively used in micro-and nano satellite propulsion systems. However, most of these propellants exhibit poor controllability and produce massive amounts of residual by-products. Laser-controlled gel propellants have been confirmed to be the most effective solution to address these issues in this study. The present study exhibits the preparation of ADN-based laser-controlled gel propellants using the freeze–thaw method and their controllable combustion characteristics under laser irradiation. The results show that the ignition delay time of gel propellants decreases from 93.0 ms to 34.6 ms, the extinction delay time is stable at around 2 ms, and the average burning rate increases from 0.6 mm/s to 1.5 mm/s under continuous laser irradiation with the power density ranging from 0.6 to 1.3 W/mm2. The average utilization rate of gel propellant is as high as 99.2 %. Upon testing, the residual solid matter was identified as unreacted propellant that had not been irradiated by the laser. Laser-controlled gel propellants represent a new type of energetic material that can be modulated to control its ignition, extinction, and burning rate. These capabilities overcome the challenges associated with the inability of traditional chemical propellants to extinguish and restart, thereby fulfilling the propulsion system requirements of micro-nano satellites.

Revealing flow structures in horizontal pipe and biomass combustor using computational fluid dynamics simulation

AbstractComputational fluid dynamics (CFD) is a powerful tool to provide information on detailed turbulent flow in unit processes. For that reason, this study intends to reveal the flow structures in the horizontal pipe and biomass combustor. The simulation was aided by ANSYS Fluent employing standard ‐ model. The results show that a greater Reynolds number generates more turbulence. The pressure drop inside the pipe is also found steeper for small pipe diameters following Fanning's correlation. The fully developed flow for the laminar regime is found in locations where the ratio of entrance length to pipe diameter complies with Hagen–Poiseuille's rule. The sucking phenomenon in jet flow is also similar to the working principle of ejector. For the biomass combustor, the average combustion temperature is 356–696°C, and the maximum flame temperature is 1587–1697°C. Subsequently, air initially flows through the burner area and then moves to the outlet when enters the combustor chamber. Not so for particle flow, the particle experiences sedimentation in the burner area and then falls as it enters the combustor chamber. This study also convinces that secondary air supply can produce more circulating effects in the combustor.

Stable aluminum-lithium alloy fuels for solid propellants by facile surface modifying

As a highly reactive metal fuel, aluminum–lithium (Al-Li) alloy is an ideal candidate for replacing Al powders in solid propellants. However, the Li solid solution and AlLi compounds on the surface of Al-Li alloy powders display high reactivity, which can react with a large number of organic and inorganic reagents. Thus, the incompatibility of Al-Li alloy with other components of propellants makes it difficult to be further applied in propellants. In this study, surface-modified Al-Li alloy powders (Li content of 5 wt%) with 1H,1H,2H,2H-perfluorodecyltrimethoxysilane (FAS17) were prepared by a facile self-assembly method, which made the alloy powders super-hydrophobic. The results of SEM, XPS and FIB-TEM show that the surface of Al-Li alloy powder is well-coated by an evenly distributed FAS17 layer. Due to the fluoroalkyl on the surface of the powders, the water contact angle increased by 91°and the intensity of the reaction between alloy powders and water is significantly reduced, which results in improved compatibility with other components of propellants.Meanwhile, the propellant grain of surface-modified powders had fewer defects than the sample before coating, and showed original excellent combustion performance. The average combustion pressure and pressurization rate increased by ∼114 kPa and ∼8613 kPa/s, and the steady burning rate increased by 0.24 mm/s. Therefore, the surface-modified Al-Li alloy powders with FAS17 are expected to be an attractive candidate as a highly active and stable fuel in solid propellants.

Influences of ultra-low load operation strategies on performance of a 300 MW subcritical bituminous coal boiler

To reveal the operational characteristics of subcritical boilers under ultra-low loads, numerical simulations were conducted based on a 300 MW subcritical bituminous coal boiler. The impacts of boiler load and low-load operation strategies on coal combustion behavior, heat transfer process, and NOx emission were thoroughly examined. Results indicate that acceptable aerodynamic and temperature fields can still be formed at 25 % ultra-low load, but the boiler performance is significantly reduced, with the maximum cross-sectional average combustion temperature being reduced by 225.98 K compared with the full-load condition. At 25 % load, the use of only two layers of burners results in a substantial increase in NOx emission from 290.32 mg/m3 to 445.56 mg/m3. The position of in-service burners affects the region where the intense coal combustion and heat release process occurs, and using the middle three layers of burners helps to maintain heat absorption by the suspended heating surfaces and to minimize NOx emissions. Furthermore, increasing primary air velocity at ultra-low loads can promote coal combustion and heat transfer processes in the lower furnace, but increase NOx emission by 14.23 % when primary air velocity is increased from 14.90 m/s to 23.00 m/s at 25 % load. These findings provide valuable insights for optimizing the ultra-low load operation of subcritical boilers engaged in deep peak-shaving processes under the carbon neutrality goal.

Influence of sodium hydrogen carbonate, ammonium dihydrogen phosphate, and lignin-based explosion inhibitors on the sensitivity of coal dust explosion

In order to prevent coal dust explosions, this study developed a targeted environmentally friendly and efficient lignin-based explosion inhibitor. The effects of NaHCO3, NH4H2PO4, and lignin-based explosion inhibitors on the sensitivity parameters of coal dust explosions were investigated using a 20 L spherical vessel and a Hartmann tube for comparison. Furthermore, the explosion inhibition mechanisms of the three inhibitors were elucidated through SEM, conductivity, In Situ FTIR, TGA-DTG/DSC, and other testing methods. The results indicate that from the perspective of explosion sensitivity, ZA-L-NP exhibits better explosion inhibition effects than NaHCO3 and NH4H2PO4. The zeolite carrier of the composite explosion inhibitor has a fine porous structure, with some materials filling the pores of the zeolite, resulting in a rough surface of ZA-L-NP. The use of ZA-L-NP for explosion suppression has a minimal impact on the turbulent combustion rate of coal dust. Its poor conductivity provides an advantage in inhibiting coal dust explosions. All three inhibitors exhibit significant inhibitory effects on the OH functional groups in coal dust, with inhibition effects decreasing in the order of ZA-L-NP, NH4H2PO4, and NaHCO3. Using classical kinetic models, the activation energy (E) and pre-exponential factor (A) of coal dust with and without added explosion inhibitors were calculated. Analysis was conducted from the perspective of kinetic parameters such as mass residual, maximum burning rate, average burning rate, flammability discrimination index, and comprehensive combustion characteristic index. It was found that the zeolite and modified lignin (L-NP) in ZA-L-NP synergistically increased the activation energy of coal dust. The research results can provide theoretical basis for the effective prevention of coal dust explosions.

A survey study on arsenic speciation in coal fly ash and insights into the role of coal combustion conditions

Coal fly ashes (CFAs) are the low-density byproducts of the coal combustion process. Improper or uncontrolled CFA disposal poses significant environmental and health concerns due to the potential leaching of toxic heavy metals such as arsenic (As). Previous studies have investigated the content and speciation of As in different CFA samples, yet systematic information on As speciation in CFA with representative coal source and combustion conditions is still missing. Based on a recent survey study on the typical coal sources and combustion conditions across the U.S., this study selected 19 representative CFA samples to systematically investigate As speciation and potential correlations with these parameters. The composition, morphology, mineralogy, and As speciation of these CFA samples were characterized by complementary analytical, microscopic, and spectroscopic techniques. Synchrotron X-ray spectroscopy and microscopy analyses revealed the dominant As oxidation state to be As(V) and with strong associations to Ca, with the exception of 3 samples that had 19–51% As(III), likely due to the use of selective catalytic reduction (SCR) process. Principal component analysis was conducted to identify potential correlations of As concentration and oxidation state with parameters such as major element content, loss on ignition (LOI), average particle size, coal source, and combustion condition. Al2O3 and FeO content were found to capture a majority of the variability. Results from this study provide fundamental basis for understanding the correlations between coal source, combustion conditions, CFA characteristics, and As speciation, and providing insights for downstream beneficial utilization or disposal management.

Study on the influencing factors of gas-liquid two-phase explosions of hybrid methane/isoprene on the basis of bush fires

To evaluate the explosion hazard of hybrid isoprene/biogas in a primary forest environment, a 20 L spherical explosion vessel combining with a colorimetric thermometry was used to study the explosion parameters, flame structures and temperature distributions of hybrid isoprene/methane at different methane content and initial temperatures. Furthermore, the relationships between the explosion gas products and explosibility of hybrid isoprene/methane were analyzed. Experimental results showed that when the mass concentration of isoprene was 272.4 g m−3, the explosion pressure, the pressure rising rate, and the average combustion temperature reached their peak values of 0.89 MPa, 63.9 MPa s−1 and 2216 K, respectively. When the mass concentration was fixed at 272.4 g m−3, the explosibility of hybrid isoprene/methane initially enhanced and then decreased with the increasing methane volume fraction, and got the maximum values at 5 vol% methane. It was worth noting that the explosibility of hybrid methane/isoprene weakened continuously as the initial temperature increased, and it exhibited a stronger explosion power at a lower temperature. The research results would be helpful for understanding the deflagration processes and mechanisms of bush fires under various conditions, providing scientific basis for the formulation of its prevention and control measures.

Numerical and Experimental Analyses of the Effect of Water Injection on Combustion of Mg-Based Hydroreactive Fuels

The energy release process of the Mg-based hydroreactive fuels directly affects the performance of water ramjet engines, and the burning rate is one of the key parameters of the Mg-based hydroreactive fuels. However, there is not enough in-depth understanding of the combustion process of Mg-based hydroreactive fuels within the chamber of water ramjet engines, and there is a lack of effective means of prediction of the burning rate. Therefore, this paper aims to examine the flame structure of Mg-based hydroreactive fuels with a high metal content and analyze the impact of the water injection velocity and droplet diameter on the combustion property. A combustion experiment system was designed to replicate the combustion of Mg-based hydroreactive fuels within water ramjet engines, and the average linear burning rate was calculated through the target line method. On the basis of the experiment, a combustion–flow coupling solution model of Mg-based hydroreactive fuels was formulated, including the reaction mechanism between Mg/H2O and the decomposition products from an oxidizer and binder. The model was validated through experimental results with Mg-based hydroreactive fuels at various pressures and water injection velocities. The mean absolute percentage error (MAPE) in the experimental results was less than 5%, proving the accuracy and validity of the model. The resulting model was employed for simulating the combustion of Mg-based hydroreactive fuels under different water injection parameters. The addition of water injection resulted in the creation of a new high-temperature region, namely the Mg/H2O non-premixed combustion region in addition to improving the radial diffusion of the flame. With the increasing water injection velocity, the characteristic distance of Mg/H2O non-premixed combustion region is decreased, which enhances the heat transfer to burning surface and accelerates the fuel combustion. The impact of droplet parameters was investigated, revealing that larger droplets enhance the penetration of the fuel-rich gas, which is similar to the effect of injection velocity. However, when the droplet size becomes too large, the aqueous droplets do not fully evaporate, resulting in a slight decrease in the burning rate. These findings enhance the understanding of the mechanisms behind the burning rate variation in Mg-based hydroreactive fuels and offer theoretical guidance for the optimal selection of the engine operating parameters.

CFD modeling and industry application of a self-preheating pulverized coal burner of high coal concentration and enhanced combustion stability under ultra-low load

Deep participation in peak regulation is a fundamental issue in flexible peak regulation. The ability to operate coal-fired power units under ultra-low load plays a crucial role in China’s pursuit of its energy goals. This study focuses on the performance analysis of a self-preheating pulverized coal burner with high coal concentration under ultra-low load conditions through simulations and experiments. A numerical comparison between the performance of a traditional swirl burner and a self-preheating burner is conducted using a 5 MW combustion test furnace. The results demonstrate that the self-preheating burner exhibits superior combustion stability and can maintain stable combustion even at an ultra-low load of 15 %. Additionally, the air distribution of the self-preheating burner under ultra-low load conditions is investigated numerically. The results reveal that under 15 % load, primary air rate of 12.0 % and internal secondary air rate of 54.2 % enable the self-preheating burner to achieve stable combustion performance with a char burnout rate of 98.6 %. Furthermore, in the absence of separated over fire air (SOFA) conditions, the NOx emission level ranges from 150 to 165 mg/m3. Based on numerical results, the self-preheating burner is implemented in an industrial setting, specifically a 29 MW coal-fired industrial boiler demonstration project. The results indicate that the self-preheating burner can achieve stable combustion at approximately 13 % load, with an average combustion efficiency of 93.24 %. The research validates the excellent performance of the designed self-preheating burner under ultra-low load conditions, which contributes to addressing the challenge of deep participation in peak regulation.

Cascade computational model for prediction impact of transient depth change on combustion parameters of certain timber species under continuous heating rate

The purpose of this research is to examine the effects of depth variation and exposure duration on the combustion characterization of the Maple wood species (Acer platanoides L.) and Walnut (Juglans regia L.) according to ISO 5660–1 in case of exposing the specimens to a constant heating rate 50 kWm−2. The delivered experimental data by cone calorimeter apparatus is used to train, test, and validate the optimized cascade forward artificial neural network with topology 2–8–8–12–2. This structure is simulated to predict the target parameters: the heat release rate (HRR) and the mass burning rate (MBR). With real systems, it is possible to achieve a reasonable performance and the closest approximations for the cascade model. The experimental combustion parameters: time of flame out, average specific mass burning rate, total heat release, maximum average rate of heat emission, and fire growth index are considered to make a systematic analysis and assessment with change depth. Three regions are considered for investigation of output target curves, thermally thin (d ≤ 1.1 cm), thermally medium (1.1 cm < d< 1.5 cm), thermally thick (d≥ 1.5cm). The findings demonstrate that independent of exposure period, an increase in depth change causes a sizable reduction in the HRR and MBR. Beyond 1.5 cm of depth in thermally thick regions, there is no discernible effect of time instant on changes in target parameters. In contrast, HRR and MBR gradients across depth in thermally thin regions are striking.

In situ synchrotron X-ray diffraction study of synthesis reactions in mechanically activated Ti + Al powder mixture under linear heating conditions

In the present work, we studied the features of phase formation in mechanically activated Ti + Al powder mixture at various heating rates for the first time. The study was carried out using high-resolution diffractometry method which made it possible to study the processes of phase formation in situ at any stage of heating. It was established that ignition of the activated mixture can be initiated in the solid phase with an extremely low content of reaction products formed at the preheating stage. An increase in the heating rate leads to a decrease in the average burning rate and an increase in the ignition temperature. At high heating rates, the ignition is initiated in the presence of a liquid phase when the ignition temperatures are close to the melting temperature of aluminum. In this case, the content of reaction products formed during preheating stage is relatively high. It was found that the all main compounds presented in the equilibrium diagram of Ti-Al system are synthesized in parallel. The content of phases in the reaction products depends on the heating rate.

Characteristics of temperature uniformity system in multi-tier drying equipment with sharp turning technology

Drying is a process of heat and mass transfer that occurs on the surface and within the material to be dried. It helps reduce the internal moisture of the material, inhibiting the growth, damage, and chemical changes of microorganisms during storage, thus extending the shelf life of dry materials and improving the quality of raw materials. This study aims to test multi-level drying equipment using combustion heat with a square shape and racks inside it used as the drying space for the material. The raw material was placed on racks made of perforated metal. This research started from designing the drying equipment system, fabricating and testing system. The drying system was tested using fish and cocoa beans as sample materials. The tested equipment system included temperature distribution in the combustion chamber, distribution system of hot combustion gases through sharp turning technology, uniform temperature distribution in the drying chamber with 8 levels of racks, each capable of holding a load of 10 kg, and testing of the chimney system. The research findings concluded that to maintain a drying chamber temperature of 90⁰C, an average combustion chamber temperature of 339⁰C was required. The average combustion chamber temperature needed to maintain a drying chamber temperature of 80⁰C was 290⁰C. For a drying chamber temperature of 70⁰C, an average combustion chamber temperature of 314⁰C was required. The temperature distribution inside the drying chamber moves horizontally, indicating that the temperature distribution in the drying chamber was uniform for each drying rack.

PENGARUH VARIASI DIAMETER PULI TERHADAP KONSUMSI BAHAN BAKAR MESIN PEMIPIL JAGUNG TIPE MCT 5-60

Abstract Corn is one of the main ingredients that can be processed into several types of food to meet the needs of the community. The process of processing corn using tools is growing rapidly along with technological advances so as to provide convenience for the community, especially farmers, in processing agricultural products. The machine used is a sheller type which is expected to reduce long processing times and save fuel costs if used in the long term. The purpose of this study was to determine the effect of variations in pulley diameter on fuel consumption of the MCT 5-60 corn sheller engine using a Mct 5-60 15 sheller engine and an additional GX 160 diesel engine with a power of 5.5 PK for the purpose of experimenting data collection with pulley 2 inch, 2.5 inch, and 3 inch with a fixed rpm of 1500 at the time of this test with 3 trials each. Specific fuel consumption is defined as the amount of fuel used to produce a unit of power to determine the effect of variations in pulley diameter on fuel consumption. The test method uses the experimental method, namely by changing the variation of the diameter of the pulley on the engine that is driven with a load of 3 kg, the diameter of the pulley is 2 inch, the fuel is 16 ml and the average time is 2.27 minutes, the pulley is 2.5 inch the average material burn 12 ml and the average time is 1.22 minutes. The 3 inch pulley is 5 ml and the average time is 1.04 minutes. and the size of the diameter of the pulley which is driven by a 4.5 inch diameter engine and the best results on a 3 inch diameter pulley with an average fuel consumption of 5 ml and an average testing time of 1.04 minutes.

124 Numerical Cut Points for Mild, Moderate and Severe Pain in Adult Burn Survivors

Abstract Introduction The optimal numerical cut points for mild, moderate, and severe burn pain have been established. Investigators at a single center determined that average burn pain can be categorized as mild (0-2), moderate (3-5), and severe (6-10). To address concerns about small sample size and limited diversity, we aimed to identify the most suitable average pain intensity rating scores for mild, moderate, and severe pain in a large, diverse cohort of adult burn survivors using a Patient Reported Outcome Measures Pain Interference (PROMIS-PI) short form. Methods Average 11-point pain intensity Visual Analog Scale (VAS) or Numerical Rating Scale (NRS) scores (0-10) and a customized PROMIS-PI 4-question short form were administered to adults with burn injury treated at 5 centers in the US at hospital discharge (baseline) and 6, 12, 24-months and 5-years post-injury. To identify pain intensity scores that best represent mild, moderate, and severe pain, F value statistics associated with multiple ANOVA comparisons for mean pain interference scores by various pain intensity cut points were computed. Based on previous research, 6 possible cut points (CP) were compared: CP 3,6; 3,7; 4,6; 4,7; 2,5; and 3,5. The optimal cut points were considered those with the highest ANOVA F statistic. Results Data from 1,190 participants (68% male, 80% white, 22% Hispanic, mean age 46 years) and 5 study centers with VAS/NRS pain intensity and PROMIS-PI scores at one or more study timepoints were analyzed. The optimal classification for mild, moderate, and severe pain was CP 2,5 at all timepoints (see table). Conclusions This study confirms that for a diverse cohort of burn-injured adults from multiple centers within the United States, burn intensity ratings of mild (0-2), moderate (3-5), and severe (6-10) is appropriate for up to 5 years post-injury. These findings support previous research findings and continue to advance our understanding of burn pain and pain intensity reporting while providing clinicians and researchers with an objective measure that can be used for screening, treatment, quality improvement, and research. Applicability of Research to Practice Use of this numerical classification for burn pain in the adult burn survivor can be used with greater confidence in diverse populations.