The application of nanofluids has dramatically increased from the past two decades. Nanofluids have elegantly captivated the attention of researchers nowadays. At present, various papers are being ...reported dealing with this interesting domain, allied with fascinating applications. However, the nanofluids being captives these days depicts the crucial need to bestow the comprehensive review of nanofluids application in distinct domains. This paper examines the utilization of nanofluids with distinct Plate Heat Exchanger (PHE) geometries. All the reported studies are alienated to two main categories; experimental and numerical. Furthermore, critical information regarding nanoparticle size, base fluids, analytical methods, heat transfer enhancement, flow regime, and pressure drop is presented in a comprehensive table in each section. Also, it was ultimately found that all the studies; analytical, experimental and numerical gave desired and appreciable thermal performance compared to conventional fluids. Author also reported the statistical analysis for the past published papers and the results show the increasing importance of nanofluids application in plate heat exchanger. Most of the studies showed preferred thermal behaviour, heat transfer enhancement, reduction in entropy generation and reduction in exergy destruction compared to the base fluids. An increase in Reynolds number can provide better heat transfer rates. The operating temperature of nanofluids plays a key role in the effectiveness of heat exchanger and heat transfer enhancement. Almost all the studies have demonstrated the preferred nanofluids thermal behaviour in plate heat exchanger, compared to the base fluid but Chevron and Corrugated type geometry of plate heat exchanger gives the appreciable enhancement in Nusselt number.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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The main objective of the present study is to investigate the impact of nanofluid stabilization techniques (hybrid stabilization approach, i.e., a combination of different mechanical ...and chemical methods) on the stability and thermal conductivity of CeO2+MWCNT (80:20)/water based hybrid nanofluid. The nanofluid has been prepared by using the two-step method, and a broad range of ultrasonication time (30, 60, 90, 120, 150, and 180 min) has been used. Furthermore, different kinds of charged surfactants, two anionic (sodium dodecyl benzene sulfonate (SDBS), sodium dodecyl sulphate (SDS)), two cationic (cetyltrimethylammonium bromide (CTAB), distearyl dimethylammonium chloride (DDC)), and two polymers (gum Arabic (GA), PVP (polyvinyl pyrrolidone)) have been added to the base fluid with a different nanoparticle to surfactant mixing ratios (5:0, 4:1, 3:2, 2:3 and 1:4). The prepared samples were investigated at different pH values and different preparation days (15th, 30th, 45th,60th, and 90th day) to evaluate which surfactant and mixing ratios are sufficient to achieve a stable nanofluid for more than 90 days. The observed optimum volumetric mixing ratio of surfactant and CeO2+MWCNT nanoparticle, pH level and sonication time are around 3:2, 9.5, and 90 min, respectively, for which hybrid nanofluid yields maximum zeta potential value as an indicator of nanofluids long term stability. The results of zeta potential analysis indicated that CTAB surfactant shows the best impact up to the 30th day from preparation, after the 30th day, the SDBS surfactant shows the highest degree of stability of the hybrid nanofluid applying 3:2 mixing ratio and 90 min sonication. Results clearly showed that the nanofluid hybrid stabilization approach has a strong relation with thermal conductivity. The addition of higher amounts of surfactant (more than 3:2 mixing ratio) caused a small thermal conductivity reduction. Additionally, precise assessments of the surfactant effect on a hybrid nanofluid's surface tension have also been studied. Finally, a correlation to predict the experimental value of thermal conductivity has been proposed from the experimental data, which could be beneficial for various heat transfer applications.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
A novel curve tube design called Triple Tube Heat Exchanger was investigated to identify the thermofluidic characteristics in the current paper. This research analysis comprises of both computational ...fluid dynamics and experimental results. A three-dimensional computational fluid dynamics model was developed using Ansys R19.1 (fluent) research package, and the k-epsilon model is used to realize the thermofluidic characteristics. In this new design, an additional tube is introduced between a double concentric tube heat exchanger. The complete analysis is done under consideration of turbulent fluid to fluid heat transfer conditions. The influence of different thermal parameters such as overall heat transfer and effectiveness were the main points of research interest by using WO3/water nanofluid with different novel inserts like twisted tape, rib, and porous plate. The thermodynamic effect of nanofluid was considered under the concentration range of 0.5%–3.0%. The computational fluid dynamics method is used to simulate the process, and experimental data is used to validate it. The result shows that the maximum overall heat transfer rate and effectiveness were 1767.91 W/m2K, 1702.71 W/m2K, and 1.86, 1.79, respectively, at 1% optimized volume concentration with WO3/water nanofluid by using rib type insert during experimental and computational fluid dynamics methods, respectively. The maximum thermal performance factor by using nanofluid in the rib type insert was observed at 0.75. The study shows an enhancement of 11.84%, 12.38%, and 14.56%, 14.30% in overall heat transfer and effectiveness by using a rib-type insert for both experimental and computational fluid dynamics methods, respectively, in comparison to without using inserts. There was also a progressive decrement in friction factor during the increment in mass flow rates.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The present experimental investigation describes the impact of surfactants (such as Benzalkonium chloride (BAC), Cetrimonium chloride (CTAC), Ammonium lauryl sulphate (ALS), PLS (Pottasium lauryl ...sulphate), Brij 700, and Span 80), sonication time (30–240 min.), and temperature (55 °C ~ 80 °C), on the stability and viscosity of hybrid nanoparticle (CeO2 + MWCNT) for different base fluids (water, silicone oil, EG, and therminol VP-I). The results of Zeta potential analysis indicated that BAC surfactant shows the best impact on hybrid nanofluid stability (HNF). The observed optimum sonication time is 60, 120, 90, and 120 min, respectively, for silicon oil, EG, water, and therminol VP-I for which HNF yields maximum zeta potential value. With the increment in operating temperature range, the stability of prepared HNF using different base fluids and adding six different surfactants has decreased. Furthermore, it is found that with the increase in sonication time, the viscosity of HNF firstly decreases up to an optimum time, after which it increases gradually. The rheological behavior of working HNF for various practical applications of the current suspensions is also reported. From 3S analysis such as sonication, surfactant, and stability, De-Ionized (DI) Water is advisable to be used as a base fluid for the particle combination of CeO2 + MWCNT with 80:20 mixture ratio as it provides long-term stability and marginal viscosity enhancement. Finally, results show that the CeO2 + MWCNT (80,20)/ DI water nano colloidal behaves as a Non-Newtonian fluid as there is no linear agreement found between shear stress and shear rate.
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•The minimum optimal sonication time is 60 min. For silicon oil among all the used different base fluid.•Silicon Oil as a base fluid bears highest value of absolute zeta potential (66 mV).•BAC surfactant shows the best impact on the stability for all different HNF.•HNF CeO2 + MWCNT (80:20)/ DI water behaves like a Non-Newtonian fluid.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
In this work, the overall thermal performance of a commercial corrugated plate heat exchanger has been conducted for the first time by varying the three different plate corrugated angles (30°, 45°, ...60°) and variable plate spacing (from 5 mm to 20 mm) working with polar solvent-based novel Silicon carbide (SiC)/DI Water nanosuspension as a coolant by focusing potential industrial application. This study aimed to identify the enhancement in thermal performance of plate heat exchanger by evaluating its overall heat transfer coefficient, pressure drop, pumping power, and exergetic efficiency by utilizing SiC/DI water nanofluid of varying volume concentration (0.20 %, 0.40 %, 0.60 %, 0.80 %, 1.00 %, 1.20 %, and 1.40 %) at ambient condition (T0 = 27 ° C), and fixed volumetric flow rate (3 L/min) for both (nanofluid and milk) sides. From the experimental results, the optimum volume concentration for the coolant was found as 0.60 %, which yields a significant enhancement in the overall heat transfer coefficient ratio by approximately 51 %, 42 %, and 38 % for 60°, 45°, and 30° corrugated plate angle respectively. The significant enhancement for 0.6 % of optimum volume concentration and 5 mm plate spacing has been reported as the best possible option at which the pumping power ratio, performance index ratio, and exergetic efficiency ratio attained the highest enhancements.
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•Novel SiC nanofluid has been tested for plate heat exchanger.•Optimum concentration for the best thermal performance of PHE is 0.60 %.•Optimum plate angle and spacing has been reported as 60° and 5 mm respectively.•Overall heat transfer coefficient ratio by ∼51 %, for 60°corrugated plate angle is achieved.•For 60° corrugated angle and 5 mm plate spacing 63.9 % exergetic efficiency enhancement is achieved.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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•Thermal performance of axial groove heat pipe has been investigated numerically.•Optimum vol.% of HNF has been reported as 1.25% for this study.•AGHP working with HNF shows a ...significant enhancement in Qmax.•The highest Qmax = 78.5 W is achieved at hg = 1.3 mm, N = 28, and α = 76°.•The current heat pipe is feasible for electronic cooling applications.
In the present study, a numerical model is developed to maximize the thermal performance of axial grooved heat pipe (AGHP) working on CeO2 + MWCNT / water based hybrid nanofluid (HNF). The effects of a wide range of volume concentration (0.25%−1.50%) at different operating temperatures (55 ℃−75 ℃) are analyzed to maximize the thermal performance of AGHP. The current numerical work aims at finding the heat transport capacity, Qmax, and total thermal resistance, Rtotal, of AGHP with acceptable accuracy by validating it with the past experimental studies. It has been observed that the highest Qmax is achieved at 1.25% of the volume concentration of HNF for each operating temperature. The novel HNF based AGHP shows an enhancement of 61.27% in the heat transport capacity and a reduction of 30% in the total thermal resistance compared to the water-based AGHP. The study is further extended by incorporating the effects of geometrical parameters on AGHP’s thermal performance. Three geometrical parameters are considered in this study, namely groove height (hg), number of axial grooves (N), and their inclination angle (α). A total of 128 combinations of N, hg, and α have been analyzed to optimize Qmax and Rtotal. The maximum thermal performance of AGHP is achieved at N = 28, hg = 1.3 mm, and α = 76°, where the Qmax = 78.5 W and Rtotal = 0.054 °C/W.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Present experimental investigation incorporates characterization of Al nanopowder, synthesis of Al/water nanofluids, and effect of these nanofluids on thermal performance of compact heat exchanger. ...Al nanoparticles are characterized using TEM and XRD. Al/water nanofluid is prepared by dispersing metal basis aluminium nanoparticles of average 100 nm size into double distilled water at two different particle volume concentrations of 0.1 and 0.2%. The nanofluids are prepared by two-step method and cetyl trimethyl ammonium bromide surfactant is used to stabilize the nanofluid. Thermo-physical properties of nanofluids at two different concentrations and their variation with fluid temperature are measured experimentally. It is examined that thermal conductivity, viscosity, and density of the nanofluid increased with the increase of volume concentrations. Furthermore, by increasing the fluid temperature, thermal conductivity is intensified, while the viscosity and density are decreased. Heat transfer parameters are strong functions of these thermo-physical properties. Therefore, comprehensive findings on heat transfer coefficient, Nusselt number, colburn factor, friction factor, and effectiveness are determined experimentally for prepared nanofluids passing under laminar conditions through single-pass cross-flow compact heat exchanger attached with multi-louvered fins.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Abstract Objectives To develop and provide initial validation for a multivariate, claims-based prediction model for disability status (DS), a proxy measure of performance status (PS), among older ...adults. The model was designed to augment information on health status at the point of cancer diagnosis in studies using insurance claims to examine cancer treatment and outcomes. Materials and Methods We used data from the 2001–2005 Medicare Current Beneficiary Survey (MCBS), with observations randomly split into estimation and validation subsamples. We developed an algorithm linking self-reported functional status measures to a DS scale, a proxy for the Eastern Cooperative Oncology Group (ECOG) PS scale. The DS measure was dichotomized to focus on good ECOG 0–2 versus poor ECOG 3–4 PS. We identified potential claims-based predictors, and estimated multivariate logistic regression models, with poor DS as the dependent measure, using a stepwise approach to select the optimal model. Construct validity was tested by determining whether the predicted DS measure generated by the model was a significant predictor of survival within a validation sample from the MCBS. Results and Conclusion One-tenth of the beneficiaries met the definition for poor DS. The base model yielded high sensitivity (0.79) and specificity (0.92); positive predictive value = 48.3% and negative predictive value = 97.8%, c-statistic = 0.92 and good model calibration. Adjusted poor claims-based DS was associated with an increased hazard of death (HR = 3.53, 95% CI 3.18, 3.92). The ability to assess DS should improve covariate control and reduce indication bias in observational studies of cancer treatment and outcomes based on insurance claims.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
BackgroundCTLA-4 is highly expressed on most regulatory T cells (Tregs) but only upregulated in effector T cells following activation. Emerging evidence suggests anti-tumor activity of antibodies ...targeting CTLA-4 may be modulated by the local presence of NK cells. Interleukin 15 (IL-15) is a pleiotropic cytokine important in both innate and adaptive immunity. The IL-15/IL-15Rα complex can stimulate adjacent cells through the IL-2Rβ/γ complex. JK08 is a recombinant fusion protein consisting of two functional elements - a fully human monoclonal antibody directed against CTLA-4 and a protein complex consisting of human IL-15 and the Sushi domain of human IL-15Rα. JK08 is intended to widen the therapeutic window for IL-15 cytokine-mediated cancer therapy and CTLA-4-targeted antibody-mediated cancer therapy by local activation and expansion of NK cells at sites of Tregs, and by IL-15 enhancement of the activity and potency of the proximal CTLA-4 antibody, mirroring the endogenous trans-presentation orientation. Preclinical studies demonstrate JK08 can elicit ADCC-mediated killing of CTLA-4-expressing cells and interact with IL-2Rβ on NK & CD8+ T cells to promote robust T cell proliferation independent of IL-15Rα expression, suggesting that JK08 could effectively activate IL-2Rβ/γC-expressing cells preferentially at sites of Tregs and achieve enhanced anti-tumor responses including through ADCC-mediated depletion of T regulatory cells. In vivo studies show JK08 induces robust NK and CD8+ T cell expansion in cynomolgus monkeys and anti-tumor activity in syngeneic murine models.MethodsThe Phase 1/2 study of JK08 will enroll patients with advanced relapsed/refractory solid tumors. The study will employ an accelerated 3+3 escalation design to explore the safety, PK, immuno-regulatory activity, and preliminary anti-tumor activity of JK08. Patients will receive treatment with JK08 subcutaneously once weekly until confirmed disease progression or intolerable toxicity. Tumor specific expansion cohorts will be initiated once dose and schedule are established from dose escalation, with plans to further advance development in combinations. Response will be assessed every 9 weeks per RECIST v1.1.
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