7 results about "Heat mass transfer" patented technology

This invention relates to the field of design simulation technology, specifically to a method for predicting the heat and mass transfer performance of a combined wet and dry cooling tower based on numerical simulation. The method includes the following steps: collecting structural parameters, operating parameters, and physical property parameters of the combined wet and dry cooling tower, and establishing a coupled numerical equation for energy balance. This invention obtains the current number of segments, calculates the variance of the segmented heat flux density values ​​based on the structural parameters and heat transfer values; dynamically adjusts the number of segments according to the variance of the segmented heat flux density values ​​to obtain the adjusted number of segments, and calculates the outlet temperature difference; then performs numerical iterative convergence based on the outlet temperature difference. By abandoning the traditional model of a fixed number of segments and dynamically adjusting the segments based on the real-time heat flux density distribution, the calculation accuracy is improved in areas with large heat flux fluctuations, and the calculation efficiency is improved in areas with small fluctuations, thereby improving the iterative convergence speed and prediction accuracy.

This invention relates to the field of power cable technology, specifically to a phosphorus-nitrogen flame-retardant modified polyolefin sheathed power cable and its preparation method, comprising the following raw materials in parts by weight: 40-60 parts ethylene-vinyl acetate copolymer, 15-25 parts metallocene polyethylene, 80-140 parts composite flame retardant, 10-20 parts composite additive, 0.8-1.5 parts antioxidant, 1.5-2.5 parts lubricant, and 2-3.5 parts silicone masterbatch. In this invention, a synergistic flame-retardant system is constructed through the first and second additives of the composite additive. The first additive forms a dense char layer to block heat and mass transfer, while the second additive further enhances the flame-retardant effect and inhibits smoke generation. Combined with the pretreatment modification of metallocene polyethylene, it avoids the agglomeration of flame-retardant components and improves compatibility. Together with the composite additive, it synergistically inhibits flame spread, reduces smoke toxicity release, and improves the flame-retardant efficiency of the cable sheath.

This application discloses a method for the continuous preparation of ethephon, belonging to the field of ethephon preparation. The method includes the following steps: pre-dispersing bis(2-chloroethyl)-(2-chloroethyl)phosphonate, ethephon, and hydrogen chloride gas to obtain a gas-liquid dispersion with a dispersed phase size ≤1 mm; conveying the gas-liquid dispersion to a micro-packed bed reactor for reaction to obtain reaction products; and separating the reaction products to obtain a liquid-phase crude ethephon product. This application, by pre-introducing ethephon into the reaction feedstock system and enhancing the dispersibility of the feedstock system, can accelerate the heat and mass transfer process of the reaction system, significantly improve reaction efficiency, and avoid the generation of by-products. It features high feedstock conversion rate, high product purity, high product space-time yield, and short reaction time, enabling efficient, safe, and continuous production of ethephon with broad application prospects.

This invention discloses a method and continuous production apparatus for polymerizing polyarylene ether nitrile from 2,6-dichlorobenzonitrile and mixed diphenols, belonging to the field of polymer material synthesis technology. The method includes: mixing 2,6-dichlorobenzonitrile with hydroquinone / bisphenol A at a molar ratio of (0.3~0.7):(0.7~0.3), followed by azeotropic dehydration and step-temperature polycondensation in an alkaline catalyst and organic solvent to obtain a polymer viscous liquid; diluting the viscous liquid and spraying it into a 50%~70% ethanol aqueous solution through a high-pressure nozzle to achieve pressurized spray precipitation; subjecting the precipitated solid to multi-stage hot water washing and continuous vacuum drying using a continuous belt filter to obtain the finished product; recovering the solvent from the mother liquor by distillation; and recycling the wastewater after ultrafiltration membrane treatment. This invention effectively balances the rigidity and solubility of the polymer by controlling the ratio of mixed monomers, and significantly improves the heat and mass transfer efficiency of the high-viscosity system by employing pressurized spray precipitation and continuous washing and drying processes, solving the industry pain points of traditional batch precipitation such as easy agglomeration, high solvent residue, and high water consumption.

This invention discloses an inclined falling film generator that enhances the heat and mass transfer of ammonia water through ultrasonic oscillation atomization coupling. The generator includes a housing containing several inclined falling film tubes. A downward-flowing falling film solution flows outside the tubes, while an upward-flowing heat source flows inside. The falling film solution is heated by the heat source, generating rising vapor that exits at the top of the generator. Multiple sets of ultrasonic atomizers and ultrasonic oscillators are spaced apart on the outside of each falling film tube. The high-frequency ultrasonic atomizers atomize the falling film solution into fine droplets, which exchange heat and mass with the rising vapor whose temperature decreases progressively along the falling film height, thus improving the purity of the generator outlet and reducing irreversible losses. The medium- and low-frequency ultrasonic oscillators enhance internal disturbances in the solution, strengthening heat and mass transfer. This invention effectively utilizes the stepped heat distribution of the rising vapor within the generator, improving the purity and quality of the generator outlet, enabling miniaturization of the generator equipment and improving system performance.

This invention belongs to the field of polymer technology, specifically relating to a method, system, and device for calculating the porosity of a hydrogen-sensitive colorimetric detection gel. It aims to solve the problems of existing tape detection methods, such as limited detection range, reliability limited by tape thickness and adhesion, and susceptibility to missed detections; and the complex preparation and poor final product quality of hydrogels, where porosity cannot be accurately calculated. This invention includes: a set of heat and mass transfer equations characterizing hydrogen molecule diffusion in a hydrogel, expressed in dimensionless form; obtaining equations for hydrogen flow and diffusion migration in the hydrogel by combining boundary motion constraints; solving for the physical properties of the material and calculating the hydrogel porosity; and preparing the hydrogen-sensitive colorimetric detection gel based on the hydrogel porosity. This invention calculates the porosity of the hydrogel and controls porosity during preparation, achieving precise location detection of hydrogen leaks, reducing the likelihood of missed detections. The preparation process is simple, the gel is recyclable, and the cost is low and safety is high.

This invention provides an internal component and method for enhancing the guided mass and heat transfer in a fixed bed. Through a biomimetic guided flow network formed by the main channel and branch channels, combined with active gas supply, the internal flow field of the fixed bed is actively regulated and uniformly distributed. The vertically arranged main channel, along with the asymmetrically distributed branch channels, effectively eliminates dead zones caused by fluid inertia within the bed. Multi-stage vents on the branch channels decompose the concentrated airflow into multiple micro-scale jets, forming a secondary flow field through airflow-wall interaction. This significantly enhances momentum exchange and heat transfer between the gas and solid interfaces, solving the problems of local turbulence, dead zones, low heat and mass transfer efficiency, and uneven temperature distribution in traditional fixed beds due to the lack of active guided flow and reliance on passive mass and heat transfer. This provides a reliable guarantee for continuous reaction under high temperature and high pressure conditions.