Split Flow Research Articles

Modeling and simulation of a split and recombination-based passive micromixer with vortex-generating mixing units

As a state-of-the-art technology, micromixers are being used in various chemical and biological processes, including polymerization, extraction, crystallization, organic synthesis, biological screening, drug development, drug delivery, etc. The ability of a micromixer to perform efficient mixing while consuming little power is one of its basic needs. In this paper, a passive micromixer having vortex-generating mixing units is proposed which shows effective mixing with a small pressure drop. The micromixer works on the split and recombination (SAR) flow principle. In this study, four micromixers are designed with different arrangements of mixing units, and the effect of the placement of connecting channels is evaluated in terms of mixing index, pressure drop, and mixing performance. The channel width of 200 μm, height of 300 μm, and size of mixing units are maintained constant for all the micromixers throughout the evaluation process. The numerical simulation is performed for the Reynolds number (Re) range of 0.1–100 using Comsol Multiphysics software. By categorizing the flow patterns into three regimes based on the range of Re, the fluid flow throughout the length of the micromixer is visualized. The micromixer with dislocated connecting channels provides a satisfactory result with the mixing index of 0.96 and 0.94, and the pressure drop of 2.5 Pa and 7.8 kPa at Re = 0.1 and Re = 100 respectively. It also outperformed the other models in terms of the mixing performance. The proposed micromixer might very well be used in microfluidic devices for a variety of analytical procedures due to its straightforward construction and outstanding performance.

Retrofit of the acid gas sweetening process for the refinery based on exergy analysis method

Although the acid gas sweetening process in the petrochemical and natural gas industries has continually improved over the past few decades, the energy consumption and process optimization remain a challenge. In this study, based on the process simulation and exergy analysis, the bottlenecks of a typical acid gas sweetening process for the refinery was analyzed using Aspen HYSYS, and the optimization strategies were discussed and proposed. First, a novel low temperature absorption with a lean solvent temperature of 15 °C was developed coupled with the recovery of cold energy of sweet gas, which improved the absorption efficiency and reduced the circulation rate of lean solvent. Then a modified heat pump distillation combining split flow feeding technology was developed. After optimization of the novel process developed, the results indicated that operating cost and overall energy consumption was dramatically reduced by 14% and 22% for the absorption process respectively, and combined with the modified regeneration process, the energy recovery efficiency was further improved. The operating cost, the comprehensive energy consumption and the TAC were totally reduced by 19.3%, 30%, and 13.1%, respectively. Finally, the primary investment analysis indicates that the retrofits are feasible, which provides an alternative for the acid gas sweetening.

Performance Evaluation of Hybrid Fibre Reinforced High Volume Fly Ash based Self Compacting Concrete

Self-compacting concrete has become increasingly popular lately for usage in crowded concrete-reinforced buildings having challenging casting circumstances. New cement needs to have high fluidity and strong cohesion for these applications. The necessary concrete characteristics can be ensured through the use of fine elements like fly ash. The preliminary findings of a trial to produce and assess SCC created using large amounts of Fly ash is given and discussed. During this investigation, few SCC combinations and a control concrete is examined. The water/cementitious material ratio is ranges from 0.35 while cementitious material amount remained constant (300 kg/m3). Its self-compacting mixes replaced 25%,35%,37.5%,40%, and 50%, of the cement with fly ash. All mixes were put through tests to determine their viscosity and stability as fresh concrete. Additionally, the compressive strength, Flow Ability Test, Flexural strength and Split Tensile Strength of cured concretes were measured. For the purpose of testing the flow characteristics and mechanical properties of Hybrid Propylene Steel Fibre Self-Compacting Concrete (HPSscc), Steel Fibre in combination with Poly Propylene PP Fibre (Hybrid Fibre) are used to regulate SCC at concentrations of 0.25+0.15%, 0.50+0.30%, 0.75+0.45%, 1.0% + 0.60%, and 1.25+0.75%.The ideal quantity of hybrid fibre is established. The 28-day compressive strengths of the SCCs ranged from 35 to 54 MPa. It is important to research the effects of adding steel fibres to control SCC of various types, aspect ratios, and volume fractions. Concrete can benefit from having its tensile strength increased by using synthetic fibres like polypropylene PP. It is important to achieve the ideal quantity of PP fibres to be added for a specific characteristic of the mix's constituents. Hybrid fibre is used in concrete when more than one fibre is included. The performance of concrete can be improved by using the characteristics of one type of fibre with another type of fibre. Also Flow Ability Test carried out immediately after producing concrete earlier and Split Tensile Strength tests are conducted. The outcomes demonstrate that a cost-effective SCC might be successfully constructed by adding significant amounts(35%) of fly ash.

Human decision change in crowd evacuation: A virtual reality-based study

In complex building evacuations, continuous decision-making is unavoidable to make a sequence of route choices at intersections. Evacuees can change their initial decisions with the environmental context changes to deal with the uncertainties of the evacuation. However, this decision-changing phenomenon in evacuation wayfinding has not been well explained. Therefore, this study investigates the decision-changing behavior in crowd evacuation. The influence of two typical crowd flow modes (i.e., symmetric split and asymmetric split crowd flow) on human decision changes in evacuation wayfinding is explored. The results show that evacuees are likely to change their initial route choice decision under the influence of crowd flows, and asymmetric crowd flow significantly reinforces this trend. Moreover, crowd flow modes significantly affected participants' wayfinding performance, including evacuation time, distance, and speed. This study provides behavioral observations and empirical evidence of the persistent effects of crowd flows on evacuees' wayfinding decisions changing and performance during the evacuation.

Research on the geometry performance of a double-vortex coiled tubing friction-reducing tool based on the Coanda effect

There are some problems in coiled tubing drilling in deep horizontal sections, such as large buckling friction and difficult extension drilling. To solve this problem, the double vortex friction-reducing tool based on the Coanda effect is adopted. However, the structure of the tool is complex, there are few studies on the influence of geometric parameters on the vibration characteristics, which is difficult to provide a reference for tool structure optimization. Therefore, based on the Coanda effect, this work establishes a numerical model of the double vortex friction-reducing tool, and the influence of different geometric parameters on the vibration characteristics of the double vortex friction-reducing tool was studied. The results show that the variation of geometric parameters of the double vortex friction-reducing tool not only affects the pressure drop and oscillation frequency, but also affects the changing process of the pressure drop. To ensure that the tool can produce good oscillation characteristics, it is recommended that the width of split flow channel is 6∼9 mm, the distance between cleft tip and jet orifice is 38∼44 mm, the width of feedback channel is 3∼5 mm and the distance of between vortex chambers is 32∼36 mm. The research results have important guiding significance for the design and structure optimization of double vortex friction-reducing tool.

Split Second Analysis Covering High Pressure Gas Flow Dynamics At Pipe Outlet – Mathematical / CFD Investigation

Split Second Analysis Covering High Pressure Gas Flow Dynamics At Pipe Outlet – Mathematical / CFD Investigation

Optimising the analysis of Anacardiaceae (Asian lacquer) polymers using pyrolysis-gas chromatography-mass spectrometry

The identification and differentiation of Anacardiaceae or Asian lacquer polymers is a challenging task, however, the characterisation of these lacquers is highly relevant, especially there is a need to understand the degradation of the polymers and the effects of conservation treatments. To improve the characterisation of artificially light aged polymers from Gluta usitata, Toxicodendron succedaneum and Toxicodendron vernicifluum, using pyrolysis-gas chromatography-mass spectrometry (Py-GC-MS), the effects of pyrolysis temperature and the use of online derivatisation were studied in detail. Derivatisation was based on trimethylsilylation with hexamethyldisilazane (HMDS) and hydrolysis and methylation with tetramethylammonium hydroxide (TMAH). The results showed that stepwise increasing the flash pyrolysis temperature is helpful to differentiate between primary pyrolysis reactions and the formation of secondary products. This approach was invaluable to reconstruct the polymeric structure of these lacquers, based on the identified pyrolysates, and the peak areas obtained at specific pyrolysis temperature ranges. Derivatisation of polar compounds in the samples proved a requirement to obtain reliable data. Even though the HMDS based results were found to be inferior to the obtained TMAH data, in terms of derivatisation efficiency and overall analytical repeatability, HMDS was more selective towards alkenylcatechols. This appeared primarily for alkenylcatechols comprising the T. succedaneum polymer and for the analysis of carbohydrates, in samples of all polymeric types. Lowering the split flow, showed that the derivatisation efficiency with HMDS was much improved. Using the reduced split flow method also allowed for e.g., better identification of resorcinol isomers in G. usitata polymers.

Implementation of Vertical Split Flow Model for Patient Throughput at a Community Hospital Emergency Department

BackgroundHospitals have implemented innovative strategies to address overcrowding by optimizing patient flow through the emergency department (ED). Vertical split flow refers to the concept of assigning patients to vertical chairs instead of horizontal beds based on patient acuity. ObjectiveEvaluate the impact of vertical split flow implementation on ED Emergency Severity Index (ESI) level 3, patient length of stay, and throughput at a community hospital. MethodsRetrospective cohort study of all ESI level 3 patients presenting to a community hospital ED over a 3-month period prior to and after vertical split flow implementation between 2018 and 2019. ResultsIn total, data were collected from 10,638 patient visits: 5262 and 5376 patient visits pre- and postintervention, respectively. There was a significant reduction in mean overall length of stay when ESI-3 patients were triaged with vertical split flow (251 min vs 283 min, p < 0.001). ConclusionsCommunity hospital ED implementation of vertical split flow for ESI level 3 patients was associated with a significant reduction in overall length of stay and improved throughput. This model provides a solution to increase the number of patients that can be simultaneously cared for in the ED without increasing staffing or physical space.

Combining amperometry and mass spectrometry as a dual detection approach for capillary electrophoresis.

Dual detection concepts (DDCs) are becoming more and more popular in analytical chemistry. In this work, we describe a novel DDC for capillary electrophoresis (CE) consisting of an amperometric detector (AD) and a mass spectrometer (MS). This detector combination has a good complementarity as the AD exhibits high sensitivity, whereas the MS provides excellent selectivity. Both detectors are based on a destructive detection principle, making a serial detector arrangement impossible. Thus, for the realization of the DDC, the CE flow was divided into two parts with a flow splitter. The DDC was characterized in a proof-of-concept study with ferrocene derivates and a nonaqueous background electrolyte. We could show that splitting the CE flow was a suitable method for the instrumental realization of the DDC consisting of two destructive detectors. By lowering the height of the AD compared to the MS, it was possible to synchronize the detector responses. Additionally, for the chosen model system, we confirmed that the AD was much more reproducible and had lower limits of detection (LODs) than the MS. The LODs were identical for the DDC and the single-detection arrangements, indicating no sensitivity decrease due to the CE flow splitting. The DDC was successfully applied to determine the drug and doping agent trimetazidine.

Optimum design of inline gas-liquid cyclone separator for wide range of inlet gas volume fractions

ABSTRACT The inline gas-liquid cyclone separator has been gradually used in oil & gas industry due to its high separation efficiency and less footprint. However, under the inlet flow conditions with large range of gas volume fractions, the research on structure design and separation performance are seriously insufficient. The preliminary structural design of the inline gas-liquid separator was carried out according to the particle separation theory, and the key structural parameters were optimized by using the Response Surface Method (RSM) together with Computational Fluid Dynamics (CFD). The structure optimization has improved the degassing efficiency by 17.44% and dehydration efficiency by 7.59%. With air and water as working medium, the separation performance of the inline gas-liquid cyclone separator was experimentally investigated in laboratory under a large range of gas volume fractions. The results show that the separation efficiency for both degassing and dehydration can exceed 80% with the inlet gas volume fraction ranges from 0.2 to 0.8. The optimum normalized flow split and liquid volume flow rate are 0.9 –1.2 and 8 m3/h, respectively.

Effects of gap configuration on vortex-induced vibration of twin-box girder and countermeasure study

To investigate the effect of the gap configuration on the vortex-induced vibration (VIV) of a twin-box girder, spring-supported sectional model wind tunnel tests of twin-box girders with different gap configurations are conducted. The gap ratio (B/D, where B is the gap width of the twin-box girder and D is the central height of the girder) is fixed at 2.74. All the tested models undergo evident vertical VIV. The wind tunnel test results show that the gap configuration significantly affects the VIV response. Two-dimensional (2D) computational fluid dynamics (CFD) simulations are performed to study the VIV mechanism of a twin-box girder. The flow characteristics of the twin-box girder are studied, and the results of the fluid-structure interaction are obtained using CFD simulations. To explore the mitigation devices for VIV, seven schemes are employed for the same scaled sectional model. The results indicate that the proposed flow splitter plate device efficiently suppresses the VIV of the twin-box girder.

Design and performance study of a two-stage inline gas-liquid cyclone separator with large range of inlet gas volume fraction

With the advantages of high separation efficiency and less footprint, the inline gas-liquid cyclone separator has gained wide attention in the fields of petroleum, chemical industry, nuclear energy and aerospace. However, single-stage gas-liquid cyclone separator usually cannot accommodate a large range of inlet gas volume fractions. For gas-liquid cyclone separator operating in series with the same structure, it is difficult to operate the second stage efficiently. Therefore, a new two-stage inline gas-liquid cyclone separator is designed in this study considering the bubble size and the variation of inlet gas volume fraction. It integrates the advantages of horizontal and vertical inline gas-liquid cyclone separator, so as to meet the separation requirement for both gas and liquid. The tangential velocity, gas volume fraction and pressure distribution inside the separator are studied by numerical simulation using Computational Fluid Dynamics. The experimental results show that the optimal standardized flow split is about 1.0. When the inlet gas volume fraction varies from 10% to 90%, the degassing efficiency gradually increased with a maximum value of 8.88%. Meanwhile, the dehydration efficiency gradually decreases, with a maximum value of 4.24%. In addition, the maximum pressure drop of the two-stage inline gas-liquid cyclone separator is only 140 kPa during the process of experimental test. This research can provide efficient solution to the working condition with wide range of inlet gas volume fraction and to meet the requirement of high compactness as well.

Online Pressure Change Focusing-Supercritical Fluid Selective Extraction Chromatography for Analyzing Chiral Drugs in Microliter-Scale Plasma Samples.

The online coupling technique of sample preparation with chromatography is a frontier topic in analytical chemistry since it minimizes errors caused by sample loss, shortens analysis time, and reduces solvent consumption. An online pressure change focusing-supercritical fluid selective extraction chromatography (PCF-SFSEC) technique was developed in this study, realizing extraction, purification, separation, and detection in a single run with only microliter-scale samples. The pressure change focusing strategy achieved column-head stacking by decreasing the dissolving capacity of the supercritical fluid, enabling the large volume introduction of extractants into supercritical fluid chromatography without causing peak broadening or distortion. All the extracts could be directly loaded into the chromatography system without split flow. Based on the supercritical fluid selective extraction (SFSE) strategy, the sorbents removed interferences and water from samples, effectively alleviating matrix effects and realizing the direct aqueous sample analysis. The efficiency of online PCF-SFSEC was demonstrated by the enantioselective analysis of 22 chiral drugs in rat plasma, covering eight categories with different pharmacological effects. The entire analysis took 25 min, consuming only 5 μL samples. All analytes in PCF-SFSEC obtained sharp and symmetrical peaks with resolutions higher than 1.0, and 86% had resolutions higher than 1.5. Limits of quantification (LOQs) ranged from 0.0600 to 32.1 μg/L. Recoveries were in the range of 75.8-117.2%. In addition, the developed approach obtained more satisfactory repeatability and significantly reduced matrix effects than conventional methods. The newly established online PCF-SFSEC technique is believed to be a green and powerful tool for the chiral analysis of complex samples.

Techno-economic analyses of Sulfinol-based absorber-stripper configurations for improving the energy consumption of natural gas sweetening process

This work presents a two-step method to reduce the energy consumption (in terms of the reboiler duty) of a natural gas sweetening process via a physical-chemical solvent mixture (Step 1) followed by a techno-economic analysis of 15 different absorber-stripper configurations (Step 2). Initially, an amine-based sweetening process using a H2S-free sour gas was simulated on Aspen HYSYS and the simulation results were validated against real plant data. In Step 1, different ratios of Sulfinol-M and Sulfinol-D based sweetening process were simulated and the superior physical-chemical solvent mixture that provides the lowest reboiler duty while meeting the sweet gas CO2 product concentration specification (i.e., less than 2 mol.%) is the Sulfinol-M solvent that contains 38 wt.% methyl diethanolamine (MDEA), 40 wt.% Sulfolane, and 22 wt.% water. This Sulfinol-M based model is then optimized via a parametric analysis to further improve its performance in terms of the reboiler duty prior to Step 2. The optimized Sulfinol-M based model achieved 65% saving in the reboiler duty while fulfilling the CO2 concentration specification in product gas relative to the base case. In Step 2, four main absorber-stripper configurations, namely absorber intercooling (AI), lean amine stream split flow (LASSF), rich amine stream split flow (RASSF), and mechanical vapor recompression (MVR) along with their 11 possible combinations were simulated in an attempt to decrease the energy consumption of the process and hence, ranked based on their total cost of production (TCOP). The results revealed that the integration of LASSF + RASSF provides the best option as it achieved the lowest TCOP of $4.60 M while fulfilling the CO2 concentration in product gas and contributed to 6.39% savings in the reboiler duty compared to the optimized conventional Sulfinol-M based model.

TEA of a Unique Two-Pathways Process for Post-Combustion CO&lt;sub&gt;2&lt;/sub&gt; Capture

A unique two-Pathways process using aqueous sodium glycinate for CO&lt;sub&gt;2&lt;/sub&gt; capture from a split flue gas stream emitted from 600 MWe post-combustion coal power plant was developed in Aspen Plus v.10. The split gas flow rate used was 44.75 ton/h and contained 0.0023 mol% SO&lt;sub&gt;2&lt;/sub&gt; and 13.33 mol% CO&lt;sub&gt;2&lt;/sub&gt;. The process includes a washing unit, a CO&lt;sub&gt;2&lt;/sub&gt; absorption unit, a reverse osmosis unit, and a solvent regeneration unit or an ultrafiltration unit. The washing unit uses deionized water to completely remove SO&lt;sub&gt;2&lt;/sub&gt; and the CO&lt;sub&gt;2&lt;/sub&gt; absorption unit uses SGS to capture at least 90 mol% of the CO&lt;sub&gt;2&lt;/sub&gt; in the split flue gas stream. Upon CO&lt;sub&gt;2&lt;/sub&gt; and SGS reactions, the resulting liquid products exhibit phase-separation into CO&lt;sub&gt;2&lt;/sub&gt;-lean phase and CO&lt;sub&gt;2&lt;/sub&gt;-rich phase, allow two distinct pathways. Pathway (i) is to regenerate mostly the CO&lt;sub&gt;2&lt;/sub&gt;-rich phase, collect the released CO&lt;sub&gt;2&lt;/sub&gt;, and compress it for sequestration purposes. Pathway (ii) is to send the liquid stream from the CO&lt;sub&gt;2&lt;/sub&gt; absorption unit to the ultrafiltration unit to separate the solid nanomaterials. The hydraulics and mass transfer characteristics in the washing and CO&lt;sub&gt;2&lt;/sub&gt; absorption units were obtained; and techno-economic analysis (TEA) for Pathways (i) and (ii), including Capital Expenditure (CAPEX), Operating Expenditure (OPEX), and Levelized Cost of CO&lt;sub&gt;2&lt;/sub&gt; Captured (LCOC), were calculated and compared. The simulation results revealed that the CAPEX, OPEX, and LCOC for Pathway (i) were ($12,039,251), (261 $/h), and (54.01 $/ton-CO&lt;sub&gt;2&lt;/sub&gt; captured), respectively, and those for Pathway (ii) were ($5,908,000), (237.2 $/h), and (39.90 $/ton-CO&lt;sub&gt;2&lt;/sub&gt; captured), respectively. Moreover, in Pathway (ii), 8.19 ton/h of CO&lt;sub&gt;2&lt;/sub&gt; were captured to produce 15.62 ton/h NaHCO&lt;sub&gt;3&lt;/sub&gt; nanomaterials, which were sold to offset the overall process cost. The LCOC values indicate that Pathway (ii) is more cost-effective than Pathway (i) because LCOC values for Pathway (ii) are much lower than those for Pathway (i).

Schooling benefits from a system of active and passive hydrofoils

Fishes school to swim more efficiently while not much of fish schooling is understood from the perspective of fluid–structure interactions. To understand the benefits of fish schooling, we investigate thrust, efficiency, and wake structure of a two-hydrofoil system where the upstream hydrofoil is forced pitching (active) and the downstream hydrofoil is free pitching (passive). The streamwise and lateral separations between the two hydrofoils are 0.109c and 1.0D, respectively, where c is the chord length and D is the diameter of the leading edge. The active hydrofoil pitches with normalized amplitudes A∗=0.55 – 0.80 and normalized frequencies StD=0.23–0.33. It is found that the upstream active hydrofoil undergoes up to 38% thrust enhancement in the presence of the downstream passive hydrofoil while the downstream passive hydrofoil achieves the same thrust as the upstream active hydrofoil under certain conditions. The maximum combined thrust and efficiency achieved for the two-hydrofoil system are 95% and 180% higher than those for a single isolated hydrofoil. These are some reasons for fish swimming in school. Three distinct flow structures (vortex impingement flow, vortex trapping flow, and vortex splitting flow) are identified in the A∗– StD domain, where the vortex trapping flow provides the greatest thrust and efficiency enhancement.

Implementation of Vertical Split Flow Model for Patient Throughput at a Community Hospital Emergency Department

Implementation of Vertical Split Flow Model for Patient Throughput at a Community Hospital Emergency Department

The Split Flow Process of CO2 Capture with Aqueous Ammonia Using the eNRTL Model

Carbon Capture and Storage (CCS) technology has attracted increasing attention as global climate change accelerates. Carbon dioxide removal processes under development include pressure swing adsorption (PSA) and chemical absorption using amine solvents. In this paper, an ammonia solvent, which is relatively inexpensive and has good material properties, was used instead of amines in the carbon dioxide removal process simulation as a chemical absorption method. This simulation used the eNRTL thermodynamics model which has the advantage of predicting ions in the liquid phase in Aspen Plus. A case study (Case Study 1) was conducted to verify the validity of the thermodynamic model. The purpose of this research was to find the operating conditions to eliminate more than 90% of the carbon dioxide contained in the flue gas from coal-fired power stations, and to lower heat duty and operating cost conditions. A second case study (Case Study 2) was conducted to find the operating conditions by comparing various process operating conditions. Additionally, this paper determined lower operating cost conditions by manipulating the amount of steam and cooling water. The results showed that the heater’s outlet temperature should be set at under 80 ℃ to lower the operating costs. As a result of changing the flow rate of the side stream of the split flow process, energy consumption was reduced when compared to the conventional flow process. It was shown that the split flow is a superior process with 10.24% less energy use than the conventional flow. In this study, the split flow process achieved an energy saving advantage when compared to the conventional flow process, and a carbon dioxide removal rate of 95% was achieved.

Supercritical Fluid Nanospray Mass Spectrometry.

Supercritical fluids are typically electrosprayed using an organic solvent makeup flow to facilitate continuous electrical connection and enhancement of electrospray stability. This results in sample dilution, loss in sensitivity, and potential phase separation. Premixing the supercritical fluid with organic solvent has shown substantial benefits to electrospray efficiency and increased analyte charge state. Presented here is a nanospray mass spectrometry system for supercritical fluids (nSF-MS). This split flow system used small i.d. capillaries, heated interface, inline frit, and submicron emitter tips to electrospray quaternary alkyl amines solvated in supercritical CO2 with a 10% methanol modifier. Analyte signal response was evaluated as a function of total system flow rate (0.5-1.5 mL/min) that is split to nanospray a supercritical fluid with linear flow rates between 0.07 and 0.42 cm/sec and pressure ranges (15-25 MPa). The nSF system showed mass-sensitive detection based on increased signal intensity for increasing capillary i.d. and analyte injection volume. These effects indicate efficient solvent evaporation for the analysis of quaternary amines. Carrier additives generally decreased signal intensity. Comparison of the nSF-MS system to the conventional SF makeup flow ESI showed 10-fold signal intensity enhancement across all the capillary i.d.s. The nSF-MS system likely achieves rapid solvent evaporation of the SF at the emitter point. The developed system combined the benefits of the nanoemitters, sCO2, and the low modifier percentage which gave rise to enhancement in MS detection sensitivity.

A comparison between fossil and synthetic kerosene flames from the perspective of soot emissions in a swirl spray RQL burner

Swirl-stabilized turbulent spray flames operating at atmospheric pressure, with both a conventional Jet-A kerosene (‘A2’) and a synthetic fuel blend (‘C5’) and radially-injected dilution air were investigated from the perspective of soot emissions in a model Rich-Quench-Lean (RQL) combustor. The primary and downstream dilution air flow split was varied while keeping the global equivalence ratio constant (ϕg=0.4). 2.5 kHz PIV, 5 kHz OH-PLIF, and simultaneous 10 Hz Mie scattering and LII were used. Results revealed a correlation between OH and soot distributions. With no dilution air, soot volume fractions (fv) peaked in a v-shaped cone between the OH-containing regions along the spray cone and those anchored to the bluff body. With dilution air at 20% of total air flow, fv shifted to the central axis as OH distributions widened. At 40% dilution, soot initiation began farther downstream along the spray cone, OH regions merged into one, and fv peaked farther downstream at the edge of the Central Recirculation Zone (CRZ). With no air dilution, peak time-averaged fv was 20% lower in the C5 flame compared to A2, despite C5 having a higher aromatics content. However, at 20% dilution fv in C5 increased by 75% compared to the no dilution case. fv in the C5 flame dropped by 12.5% in the high dilution case compared to 40% reductions in A2. Mie scattering showed that the C5 spray was shorter and more resistant to change from dilution air compared to A2. The different spray behaviours were due to C5’s flat boiling range, lower viscosity and density, leading to higher evaporation rates. Detailed chemistry laminar flamelet simulations of A2 and C5 showed that peak soot precursor species mass fraction values and temperatures decreased as the scalar dissipation increased and a significantly stronger presence of toluene in the C5 flame compared to A2. Toluene’s soot yielding behaviour may cause C5’s increased fv with moderate dilution compared to A2. C5 demonstrates the importance of the fuel’s chemical and physical properties when developing future sustainable aviation fuels for practical applications to maximize their soot mitigation potential.