INFLUENCE OF THERMOPHYSICAL PROPERTIES ON TRANSFER OF HEAT IN MULTI-LAYER DUCTS AND TEMPERATURE CONTROL USING ELECTRIC HEATING

Ensuring oil production flow in offshore systems is a critical aspect of oil exploration operations. Any interruption in the production process, whether partial or complete, can result in significant financial losses and cause solid deposition in the production line. Such deposition is due to the crystallization of paraffin and hydrates, a common problem caused by low temperatures in deep waters. Among various mitigation strategies, the Pipe-in-Pipe (PIP) system with active heating is a technological solution to address this issue. This work aimed to perform a numerical simulation of the PIP system using the Finite Volume Method with an implicit formulation, considering the effect of temperature on fluid properties and the system's dynamic response. A control loop using a PI velocity algorithm was developed to maintain the temperature above the critical point. Such simulation studies were performed using the Python programming language in the Anaconda suite. The results showed that the fluid properties greatly influence the dynamic response. The PI control maintained the temperature in the desired condition, demonstrating its operational effectiveness in preventing solid deposition and delivering stable and low-oscillatory behavior. This research emphasizes the significance of taking temperature's impact on fluid properties into account when simulating offshore oil production systems and demonstrates the effectiveness of implementing feedback control

Pulses protein quality control at different storage conditions for further protein extraction – a review: Poster

The storage conditions are of extreme importance with regards to grains (cereal & pulses) components (carbohydrates, lipids, proteins) preservation and quality for industry (that may interfere to whole process and quality of the final product). In addition, the vegetarian consumers’ interest of protein supplement (capsules) from pulses such as beans (Phaseolus vulgaris L.), chickpeas (Cicer arietinum L.), lentils (Lens culinaris L.), peas (Pisum sativum L.), peanuts (Arachis hypogaea L.), also soybeans (Glycine max L.) has grown considerably, mainly due to their non-lactose&non-animal-based ingredients and also non-transgenic in some of the pulses. Therefore, there is a need of information regarding pulses storage conditions on their components’ quality/quantity and so for safety of the raw material utilized for protein extract purposes. In addition, to get safe pulses raw materials for protein extraction aimed for vegetarian supplements, one needs to take into account (a) quite controlled storage conditions, apart from (b) pesticide residues and mycotoxins contamination control. Therefore, the present reviewgathers and compiles the characterization of six different pulses by evaluating amino acids profile as indicators of protein quality, and compares them with different varieties for further protein extraction.The storage conditions are of extreme importance with regards to grains (cereal & pulses) components (carbohydrates, lipids, proteins) preservation and quality for industry (that may interfere to whole process and quality of the final product). In addition, the vegetarian consumers’ interest of protein supplement (capsules) from pulses such as beans (Phaseolus vulgaris L.), chickpeas (Cicer arietinum L.), lentils (Lens culinaris L.), peas (Pisum sativum L.), peanuts (Arachis hypogaea L.), also soybeans (Glycine max L.) has grown considerably, mainly due to their non-lactose&non-animal-based ingredients and also non-transgenic in some of the pulses. Therefore, there is a need of information regarding pulses storage conditions on their components’ quality/quantity and so for safety of the raw material utilized for protein extract purposes. In addition, to get safe pulses raw materials for protein extraction aimed for vegetarian supplements, one needs to take into account (a) quite controlled storage conditions, apart from (b) pesticide residues and mycotoxins contamination control. Therefore, the present reviewgathers and compiles the characterization of six different pulses by evaluating amino acids profile as indicators of protein quality, and compares them with different varieties for further protein extraction

Qualitative aspects of entanglement in the Jaynes-Cummings model with an external quantum field

We present a mathematical procedure which leads us to obtain analytical solutions for the atomic inversion and Wigner function in the framework of the Jaynes-Cummings model with an external quantum field, for any kinds of cavity and driving fields. Such solutions are expressed in the integral form, with their integrands having a commom term that describes the product of the Glauber-Sudarshan quasiprobability distribution functions for each field, and a kernel responsible for the entanglement. Considering two specific initial states of the tripartite system, the formalism is then applied to calculate the atomic inversion and Wigner function where, in particular, we show how the detuning and amplitude of the driving field modify the entanglement. In addition, we also obtain the correctComment: 15 pages and 21 figure

Dicke-Type Energy Level Crossings in Cavity-Induced Atom Cooling: Another Superradiant Cooling

This paper is devoted to energy-spectral analysis for the system of a two-level atom coupled with photons in a cavity. It is shown that the Dicke-type energy level crossings take place when the atom-cavity interaction of the system undergoes changes between the weak coupling regime and the strong one. Using the phenomenon of the crossings we develop the idea of cavity-induced atom cooling proposed by the group of Ritsch, and we lay mathematical foundations of a possible mechanism for another superradiant cooling in addition to that proposed by Domokos and Ritsch. The process of our superradiant cooling can function well by cavity decay and by control of the position of the atom, at least in (mathematical) theory, even if there is neither atomic absorption nor atomic emission of photons.Comment: 15 pages; 8 figure

Optically Levitating Dielectrics in the Quantum Regime: Theory and Protocols

We provide a general quantum theory to describe the coupling of light with the motion of a dielectric object inside a high finesse optical cavity. In particular, we derive the total Hamiltonian of the system as well as a master equation describing the state of the center of mass mode of the dielectric and the cavity field mode. In addition, a quantum theory of elasticity is used in order to study the coupling of the center of mass motion with internal vibrational excitations of the dielectric. This general theory is applied to the recent proposal of using an optically levitating nanodielectric as a cavity optomechanical system [Romero-Isart et al. NJP 12, 033015 (2010), Chang et al. PNAS 107, 1005 (2010)]. On this basis, we also design a light-mechanics interface to prepare non-Gaussian states of the mechanical motion, such as quantum superpositions of Fock states. Finally, we introduce a direct mechanical tomography scheme to probe these genuine quantum states by time of flight experiments.Comment: 27 pages, revtex 2 columns, 8 figure

New remarks on the linear constraint self-dual boson and Wess-Zumino terms

In this work we prove in a precise way that the soldering formalism can be applied to the Srivastava chiral boson (SCB), in contradiction with some results appearing in the literature. We have promoted a canonical transformation that shows directly that the SCB is composed of two Floreanini-Jackiw's particles with the same chirality which spectrum is a vacuum-like one. As another conflictive result we have proved that a Wess-Zumino term used in the literature consists of the scalar field, once again denying the assertion that the WZ term adds a new degree of freedom to the SCB theory in order to modify the physics of the system.Comment: 6 pages, Revtex. Final version to appear in Physical Review