Heat Transfer and Friction Factor Correlations Development for Double Pass Solar Air Heater Artificially Roughened With Perforated Multi-V Ribs

Thermo-hydraulic performance of a Double Pass Parallel Flow Solar Air Heater (DPPFSAH) roughened with perforated multi-V ribs has been studied experimentally in a prior study and the effect of variation in open area ratio and change in relative roughness width has been analysed and reported. The current work builds upon the aforementioned earlier study by discussing in detail the methodology and various steps involved in the development of a correlation for variable parameters with Nusselt number and friction factor for DPPFSAH. The outcomes show that perforations in the multi-V ribs lead to a considerable rise in the Nusselt number, a 9.66 times increase in the thermo-hydraulic performance parameter and nearly a four times increase in friction factor compared to multi-V ribs with smoothed walls. Empirical correlations for the Nusselt number and friction factor were obtained for the double pass parallel flow solar air heater with perforated multi-V ribs established with ±14% and ±7%

Mathematical Modeling of Efficiency Evaluation of Double-Pass Parallel Flow Solar Air Heater

To investigate the influencing range and optimize values of different operational and system parameters on the double-pass parallel flow solar air heater’s (DPPFSAH) thermal, effective, and exergetic efficiencies, an iterative method was used to analyze the governing energy equations using a theoretical model written in MATLAB based on the Nusselt number (Nu) and friction factor (f) correlations developed in the work performed earlier. A comparison between double-pass and single-pass SAHs for mathematical and experimental outcomes was conducted, and the results were found to be fairly consistent. According to the thermo-hydraulic performance indicators, similar to single-pass SAHs, perforated multi-V rib-roughened DPPFSAHs achieve optimum thermal performance for lower Reynolds numbers, which does not change much as the Reynolds number increases above 18,000. This finding can be taken into account when designing any DPPFSAH

Mathematical Modeling of Efficiency Evaluation of Double-Pass Parallel Flow Solar Air Heater

To investigate the influencing range and optimize values of different operational and system parameters on the double-pass parallel flow solar air heater’s (DPPFSAH) thermal, effective, and exergetic efficiencies, an iterative method was used to analyze the governing energy equations using a theoretical model written in MATLAB based on the Nusselt number (Nu) and friction factor (f) correlations developed in the work performed earlier. A comparison between double-pass and single-pass SAHs for mathematical and experimental outcomes was conducted, and the results were found to be fairly consistent. According to the thermo-hydraulic performance indicators, similar to single-pass SAHs, perforated multi-V rib-roughened DPPFSAHs achieve optimum thermal performance for lower Reynolds numbers, which does not change much as the Reynolds number increases above 18,000. This finding can be taken into account when designing any DPPFSAH

Establishment of Trophectoderm Cell Lines from Buffalo (<i>Bubalus bubalis</i>) Embryos of Different Sources and Examination of In Vitro Developmental Competence, Quality, Epigenetic Status and Gene Expression in Cloned Embryos Derived from Them

<div><p>Despite being successfully used to produce live offspring in many species, somatic cell nuclear transfer (NT) has had a limited applicability due to very low (>1%) live birth rate because of a high incidence of pregnancy failure, which is mainly due to placental dysfunction. Since this may be due to abnormalities in the trophectoderm (TE) cell lineage, TE cells can be a model to understand the placental growth disorders seen after NT. We isolated and characterized buffalo TE cells from blastocysts produced by in vitro fertilization (TE-IVF) and Hand-made cloning (TE-HMC), and compared their growth characteristics and gene expression, and developed a feeder-free culture system for their long-term culture. The TE-IVF cells were then used as donor cells to produce HMC embryos following which their developmental competence, quality, epigenetic status and gene expression were compared with those of HMC embryos produced using fetal or adult fibroblasts as donor cells. We found that although TE-HMC and TE-IVF cells have a similar capability to grow in culture, significant differences exist in gene expression levels between them and between IVF and HMC embryos from which they are derived, which may have a role in the placental abnormalities associated with NT pregnancies. Although TE cells can be used as donor cells for producing HMC blastocysts, their developmental competence and quality is lower than that of blastocysts produced from fetal or adult fibroblasts. The epigenetic status and expression level of many important genes is different in HMC blastocysts produced using TE cells or fetal or adult fibroblasts or those produced by IVF.</p></div

Global CDX2 levels in different types of embryos.

<p>Global level of CDX2 in cloned embryos produced using trophoblast cells, adult fibroblasts and fetal fibroblasts as donor cells and those produced by IVF. Bars marked with an asterisk differ significantly from corresponding values (P<i><</i>0.05).</p

Effect of fetal fibroblast CM on growth of TE cells.

<p>Data from 3 trials. Data are Mean ± SEM. Values with different superscripts (a and b) within the same column differ significantly (P<0.05).</p><p>Effect of fetal fibroblast CM on growth of TE cells.</p

Derivation of presumptive TE cells.

<p>(A) An IVF-derived blastocyst seeded on buffalo fetal fibroblast feeder layer; (B) A primary colony of TE cells (40X, Scale bar = 500 μm); (C) A primary colony showing inner cell mass and endoderm cells (100X); (D) Endoderm colonies indicated by the arrow mark showing tight colony morphology (100X), Inset: Endoderm colony at 400X (Scale bar = 50 μm); (E) TE cells at passage 20 (200X) and (F) TE cells digested with accutase showing loosening of cells and thread-like structures which are the parts of tight junctions (400X, Scale bar = 50 μm). Scale bar = 100 μm, unless otherwise mentioned in Figure.</p

Morphology of presumptive TE cells under feeder and feeder-free conditions.

<p>Growth of IVF-derived trophoblast cells under (A) feeder and (B) feeder-free conditions. Subculture of trophoblast cells under feeder-free conditions led to development of vesicles of 100–500 μm diameter, which get dissociated (C). Following subculture, the trophoblast cells formed confluent monolayer on feeder layer (D) and dome shaped colonies under feeder-free conditions (E). Scale bar = 500 μm. Single dome observed under 100X (F). Scale bar = 100 μm.</p

Immunostaining of CDX2.

<p>(A) IVF-derived hatched blastocysts (100X) and (B) TE cells produced under feeder-free conditions showing positive expression of CDX2 (200X). Scale bar = 100 μm.</p

Effect of FGF2 on expression level of trophoblast-specific genes.

<p>Bars with different superscripts differ significantly (P<0.05).</p