Jet Condenser Research Articles

Design of a Low Power Condenser for Underwater Ships

The power unit generates heat during the operation of a ship, and excessive temperature may cause damage to equipment. Therefore, it is necessary to design a cooling system for the multi-working conditions and variable working conditions of a ship to reduce the adverse effects of high temperatures. The traditional pipeline heat exchanger is inefficient, resulting in a serious waste of resources. In this work, under the background of energy conservation and emission reduction, a new type of cooling system is designed. Using a jet condenser with direct mixing of hot and cold fluids, the technology of frequency conversion regulation is used to optimize the energy conservation of the ship’s cooling system. By adjusting the frequency of the circulating water pump and using the PID algorithm to control the flow of cooling water, the temperature of the condensate outlet can be controlled under variable operating conditions, achieving the goal of maintaining the temperature within a certain range. Because of the complex structure and controlled process of the cooling water system, which has the characteristics of non-linearity and hysteresis, PID control has some limitations. Based on this, the BP neural network is used to adjust and tune the parameters of PID control, thus optimizing the control speed and achieving accuracy in the new cooling system.

Intensification of heat transfer in a jet condenser by additional jet splitting using a grid

The intensification of heat transfer from steam to water is studied on a model of a jet condenser by splitting the falling jets using a grid installed in a steam chamber above a water layer, into which the secondary jets that are forming on the grid are immersed. The studies have demonstrated a high efficiency of this method and allowed us to reveal the key determining factors and conditions for attainment of the maximum heat transfer. The empirical dependence of the heat transfer below the grid on grid parameters and height of its location, as well as the main construction and mode parameters of the setup, is obtained. The study results were successfully tested in technological scale setups.

Accident localization system with jet condensers for VVER 440-V 230 NPP at Jaslovské Bohunice

Compared to the current world standard, the operational safety of the V1 nuclear power plant (NPP) is unsatisfactory and it does not correspond to present requirements as to nuclear safety. Further NPP operation after 1995 is conditional on nuclear safety enhancement to a level comparable with that in West European countries. This aim should be achieved by a principal reconstruction involving in addition to others also backfitting the V1 NPP with technical facilities aimed at coping with a design basis accident (DBA). To cope with such an accident the Power Equipment Research Institute (VÚEZ) designed an accident localization system with jet condensers. This system consists of (a) an air trap (one for each unit, mutually interconnected) with an expansion bell enclosed within, placed on a plate with 200 pipes of jet condensers passing through, and (b) a connecting duct between the hermetic zone and the air trap. The vertical jet condenser is an essential element of the system designed for steam condensation. Apart from condensation it serves as a water seal separating units 1 and 2. Demonstration tests of the jet condenser (model 1:1) condensing functionw were carried out at the testing unit of the All-Union Research Institute for NPP Operation (VNIIAES), Moscow in Kashir, 11–22 September 1992. These experiments proved the jet condenser ability to ensure complete condensation of the steam produced. Experimental verification of the sealing function (model 1:1) was carried out at the testing unit of the VÜEZ Tlmače. These experiments concerning the dynamics and overpressure in the free space above the pool were close to the conditions in the air trap during DBA. The jet condenser height was proved to be sufficient to ensure the sealing function. Design and experimental work has been implemented in close cooperation with Russian experts Mr. V.N. Bulynin from the VNIIAES, Moscow, and Mr. M.V. Kuznecov from the Scientific and Engineering Center for Nuclear and Radiological Safety, Moscow.

A Jet Condenser for Ocean Thermal Energy Conversion

A novel idea to use a jet condenser for Ocean Thermal Energy Conversion (OTEC) plants is presented here. The jet condenser offers the advantage of a relatively simple device. It consists of a mixing section where the partially evaporated warm water and the cold water mix and condensation takes place. After the complete condensation, the water stream is employed to drive a water turbine. The basic thermodynamic principles are evaluated. Introducing realistic efficiencies for the jet condenser, about 20 to 25 percent of the available energy can possibly be expected to be converted into mechanical energy.

Rugeley Dry Cooling Tower System

Steam power stations are one of the biggest users of water and the increasingly heavy demand for water, for all purposes, throughout the world has caused serious studies to be made of methods of providing a cooling facility for steam turbines independent of a water supply. The studies revealed that a system devised by Professor Heller provided the most economic and practical solution for large steam turbines. It uses the atmosphere as a heat sink for the turbine exhaust heat by a combination of jet condenser, closed water circuit, heat exchangers cooled by air and a cooling tower. Although there is a water circuit to be filled initially, no further water is required. The first application of the system—the dry cooling tower system—to a large turbine was designed and built by the English Electric Company Ltd for the C.E.G.B. at their Rugeley Power Station and this paper describes the project and its behaviour in service.

Steam stripping of lard

ConclusionThe rate of steam stripping of free fatty acids from lard can be evaluated in terms of a rate·constant K defined by Equations 5 and 6. Reproducible results were realized for many different batches of leaf and prime steam lards. The effects of temperature, total pressure, and steam rate were evaluated, thus making possible the calculation of stripping rate constants on a comparable basis. Comparable values of the rate constant K have been compared for conditions with and without the use of mechanical agitation with a flat‐blade mixing impeller. Use of the rotating mixing impeller showed substantial increases (30 to 50%) in the reaction rate constant, over those obtained with steam sparging without the mixer. Accordingly the use of this type mixer should result, in large savings of steam for stripping and for maintaining the necessary vacuum by the steam jet condenser.