Computational Fluid Dynamics (CFD) modeling for bread baking process — a review

Computational fluid dynamics (CFD) modeling of entire bread baking process is very complicated due to involvement of simultaneous physiochemical and biological transformations. Bread baking is a fickle process where composition, structure, and physical properties of bread change during the process. CFD finds its application in modeling of such complex processes. This paper provides the basics of CFD modeling, different radiation models used for modeling of heating in electrical heating ovens, modeling of bread baking process along with the predictions of bread temperature, starch gelatinization, and browning index. In addition, some recent approaches in numerical modeling of bread baking process are highlighted. Moreover, current limitations, recent developments, and future applications in CFD modeling of bread baking process are discussed in detail

Computational fluid dynamics modeling of bread baking process

A computational fluid dynamic (CFD) model was developed to study the temperature and browning profile of bread. This study differs from previous work of CFD modeling reported in literature in that phase change during evaporation as well as evaporation–condensation mechanism during baking process was incorporated in this model. Simulation results were validated with experimental measurements of bread temperature at three different positions. In this study crumb temperature does not cross 100 °C due to incorporation of evaporation–condensation mechanism in this model. Baking process completes within 25 min of processing time once the temperature of crumb becomes stable at 98 °C. Formation of crust and browning of bread surface were studied using earlier reported kinetic model and it predicted more browning at bread edges than the surfaces. However, predicted browning index was well within the range (< 52)

An investigation of bread-baking process in a pilot-scale electrical heating oven using computational fluid dynamics

A computational fluid dynamics (CFD) model was developed for bread-baking process in a pilot-scale baking oven to find out the effect of hot air distribution and placement of bread on temperature and starch gelatinization index of bread. In this study, product (bread) simulation was carried out with different placements of bread. Simulation results were validated with experimental measurements of bread temperature. This study showed that nonuniform air flow pattern inside the oven cavity leads to uneven temperature distribution. The study with respect to placement of bread showed that baking of bread in upper trays required shorter baking time and gelatinization index compared to those in the bottom tray. The upper tray bread center reached 100 °C at 1200 s, whereas starch gelatinization completed within 900 s, which was the minimum baking index. Moreover, the heat penetration and starch gelatinization were higher along the sides of the bread as compared to the top and bottom portions of the bread

AutoFlow® (volume-guaranteed mode) versus volume-controlled ventilation for the laparoscopic surgery with BlockBuster supraglottic airway: A randomized controlled trial

Background and Aims: Supraglottic airway devices used in laparoscopic surgeries must be efficient to counter the increased peak airway pressure (PAWP) and airway leakage that can occur in laparoscopic surgeries. Hence, the implication of AutoFlow in ventilator strategy is propounded nowadays that facilitates low PAWP and high dynamic compliance to achieve targeted tidal volume and end-tidal carbon dioxide (ETCO2). BlockBuster™ Laryngeal mask furnishing minimum airway leak. The primary objective was to compare PAWP using the two modes of ventilation through the BlockBuster LMA after intubation, pneumoperitoneum, and Trendelenburg position. The secondary objective was to observe hemodynamic vitals. Methodology: In this single-center randomized controlled trial, we recruited 80 American Society of Anesthesiologists grade I and II adult patients undergoing elective laparoscopic surgeries. They were randomized by computer-generated method into two groups: volume-controlled AutoFlow® (VCAF) and volume-controlled (VC) group. Ventilation settings for both groups set to tidal volume 5–6 ml/kg of predicted body weight, positive end-expiratory pressure 5 cm H2O, I: E ratio 1:2, and respiratory rate 12–16/min to maintain targeted ETCO2 of 30–35 cm H2O. Intraabdominal pressure was set to 14 mmHg during pneumoperitoneum and 15° Trendelenburg position. Results: Mann–Whitney U-test for continuous variables and t-test for categorical variables. Data were presented as median (interquartile range). P <0.05 was considered statistically significant. During laparoscopic surgeries with BlockBuster™ PAWP at pneumoperitoneum was (20 cm H2O vs. 27 cm H2O) and Trendelenburg position (19 cm H2O vs. 27 cm H2O) was significant lower with VCAF (AutoFlow® ventilation) than with VC (P < 0.05). Conclusion: PAWP is significantly low in AutoFlow mode as compared to volume control mode with BlockBuster LMA. In addition, LMA BlockBuster provides good sealing pressure