Maisotsenko Open Cycle Used for Gas Turbine Power Generation

Abstract

The Maisotsenko Open Cycle combines the thermodynamic processes of heat exchange and evaporative cooling in a unique indirect evaporative cooler resulting in product temperatures that approach the dew point temperature, (not the wet bulb temperature) of the working gas. It is an open thermodynamic cycle utilizing several thermodynamic processes that cools a product fluid with a liquid evaporating into a gas, generally water evaporating into air from the atmosphere and returns it to the atmosphere. It is a new cycle as no other cycle can be diagramed in the same way on the psychrometric chart of a gas. In a gas turbine, the gas is air and evaporate is water. An atmospheric pressure heat and mass exchanger operating with the Maisotsenko Cycle can be used to cool compressor inlet air below the wet bulb temperature. In a high-pressure heat and mass exchanger the cycle can create a compressed air saturator using heat from the turbine exhaust gases and also cools water for heat recovery in a compressor inter-cooler. The same saturator will humidify and/or superheat the compressed air before entering a combustor to the amount desired. From a practical stand point the limit of humidification of the compressed air is the amount of heat available at a temperature above its dew point temperature from the exhaust gas and/or intercompressor coolers. The amount of superheating or humidifying of the compressed air is easily controlled and changed during operation allowing added power, or greater efficiency, (60% overall thermal efficiency) quickly and easily. The equipment uses existing shell and tube heat exchanger or plate heat exchangers technologies. There are many other benefits ranging from lower NOx to greatly reduced equipment cost compared to any other power cycle enhancement systems.

Analysis of Maisotsenko open gas turbine bottoming cycle

“…Air is cooled down sensibly to its dew point temperature in the lower section of the air saturator [26]. Therefore, the temperature of the air at state 8 can be determined by:…”

“…An identical method is applied for the analysis of the upper section of the air saturator. Then, the exhaust gases from the topping cycle turbine are cooled down sensibly to the wet bulb temperature of the air at state 8 [26] and can be written as:…”

“…Air is saturated at state 9 [26], the mole fraction of water in humid air mixture at state 9, the saturation pressure and temperature can be calculated such that: …”

Thermodynamic Analysis of an Irreversible Maisotsenko Reciprocating Brayton Cycle

“…The configuration (the key component, Maisotsenko air saturator particularly) and the working process of the M-cycle were introduced in Reference [1]. The broad prospective applications of the M-cycle in heating ventilation, air-conditioning, the power industry, water distillation, and heat recovery have been illustrated in detail in References [2][3][4][5]. The status of the application of M-cycle expansion to the gas turbine cycle (Brayton cycle) was shown, and a comparative analysis with the traditional gas turbine cycle was carried out in References [3][4][5].…”

“…The broad prospective applications of the M-cycle in heating ventilation, air-conditioning, the power industry, water distillation, and heat recovery have been illustrated in detail in References [2][3][4][5]. The status of the application of M-cycle expansion to the gas turbine cycle (Brayton cycle) was shown, and a comparative analysis with the traditional gas turbine cycle was carried out in References [3][4][5]. The result verified that the Maisotsenko gas turbine cycle (MGTC) is superior to the humid air turbine cycle and Brayton cycle in P and η [6].…”