Turbine Ventilators Research Articles

Aerodynamic performance comparison of wind-driven turbine ventilators: A numerical investigation

Wind-driven roof ventilator is a cost-effective and environmentally sustainable solution for improving indoor ventilation and reducing energy use. This study aims to compare the ventilation performance of turbine ventilators with curved and straight blades of various sizes, utilizing both computational fluid dynamics (CFD) methods and experimental validation. Additionally, a mathematical expression is derived based on the aerodynamic principles of turbomachinery. The results indicate that both types of ventilators exhibit two streams of rotating airflow and an upward airflow. The angular velocity and ventilation rate demonstrate an approximately linear increase with higher wind speeds, and ventilators with smaller outer diameters experience a greater rate of increase in angular velocity. Larger-sized ventilators, despite having lower angular velocities, achieve higher ventilation rates for geometries of similar proportions. However, it should be noted that reducing the throat diameter may result in inadequate ventilation rates. In general, straight blade ventilators outperform curved blade ventilators, yielding 10%–38% higher ventilation rates due to their lower flow resistance. The discharge coefficients for the former and the latter are 0.32–0.37 and 0.25–0.32, respectively. The derived mathematical expression based on aerodynamics agrees well with the simulation results, providing a means for predicting ventilator performance. The objectives of this study are to enhance understanding of the ventilation performance of two types of turbine ventilators, aid in the selection and design of wind-driven roof ventilators, and promote improved indoor ventilation and energy efficiency.

Numerical investigations on roof ventilator turbine performance characteristics using ANSYS

Rooftop wind turbine ventilators are natural air circulation systems that employ a rotating blade to remove stale air from a building, improving the indoor air quality and saving money in the process. The effectiveness of a roof ventilator turbine depends heavily on its construction. By varying the diameter of the turbine blades (500, 670, and 690 mm), this CFD study modeled and examined three distinct designs for wind-driven ventilation devices. This numerical analysis was further developed to compute the presentation of a rotating ventilator by analyzing the pressure, turbulence kinetic energy, and velocity of the airflow related with the ventilator at variant designs. To investigate the viability of a numerical approach to modeling the many aspects of a ventilator flow, a computational fluid dynamics (CFD) analysis was conducted utilizing the conventional k- turbulence model with the multiple reference frame meshing method. The proposed design of a 690 mm ventilator blade for a rooftop turbine was found to perform better than two alternative designs using computational fluid dynamics (500 and 670 mm turbine blade diameter). The trend lines appear to be in virtuous contract with formerly available data, signifying that mathematical modelling could be a useful and cost-efficient tool for the design, growth, and performance evaluation of a wind-driven rotational ventilation system in the future.

Implementation Of Fuzzy Logic On Turbine Ventilators As Renewable Energy

Energy needs in Indonesia in particular and in the world in general continue to increase. One of the sources of electricity supply, PLTA together with steam power plants (PLTU) and gas power plants (PLTG) indeed play an important role in the availability of electricity. Indonesia, which is an archipelagic country and one of the countries located on the equator, is a factor that Indonesia has abundant wind energy potential. The electrical energy needs of remote communities can be met. Turbine ventilator is a device that functions to circulate air which is placed on the roof of the building that functions as ventilation in residential and industrial buildings. Based on previous research, there are those who examine the use of turbine ventilators as power plants, but there are still many shortcomings that need to be fixed. turbine ventilator that is used to catch the wind and drive the generator, by connecting the wind turbine using a v-belt so that the rotation produced by the generator is maximized. Then the generator produces electrical energy.

A novel turbine ventilator with a damper regulator to adjust exhausted air for energy-saving in buildings

Turbine ventilators are widely used for improving indoor air quality. However, the air exhaust flow rate of presently used turbine ventilators increases with wind speed, which results in a much higher air exchange rate than the required air exchange rate for air quality in the winter for heated buildings. A novel turbine ventilator with damper is developed in this paper for the energy saving of buildings under this circumstance. It could stabilise the air exchange rate in buildings to meet the minimum air quality requirement. Experiment and real site studies are conducted to test the performance of the novel device. The experiment verifies that the novel device could reduce unnecessary air exhaust flow rate when the wind speed is high compared with other presently used turbine ventilators. In a day when the wind speed is 8 m/s, the novel ventilator can reduce about 120 m3/h air volume flow compared with the presently used ventilator in both kitchen and toilet. The real site measurements show that in the conditions of city Brno-Bystrc, Czech Republic, the novel device can save about 30 EUR/y for one apartment on heating, and 2,160 EUR/y for a typical panel house (block of flats) which has three entrances, 72 apartments.

Experiments on Air Extraction Performance of Rooftop Natural Ventilators

This research experimentally investigated the air extraction performance of rooftop conventional turbine ventilator and a modified ventilator. The modified ventilator has the combined features of static and turbine ventilators, modified from the conventional ventilator where its top cover is removed and replaced by a low-pressure ventilation device. An open wind tunnel system is used for this study, which simulates the condition where the wind blows over the rooftop ventilator. The air extraction rate is determined by the air mean velocity at the open slot of a ventilation pipe connected to the ventilator. The studies include ventilator rotation speeds and air extraction rates with and without ventilator's rotating, under different wind speeds and heights of the low-pressure ventilation device. Results show that the modified ventilators exhibit better air extraction rates than the conventional one does at all of the test wind speeds, especially at low wind speeds and as the ventilator not rotating. Also, the air extraction rate is generally proportional to the total height of the low-pressure ventilation device.

Numerical Study on Air Extraction Performance of Rooftop Ventilators

This research numerically studied the air extraction performance of rooftop natural ventilators, including the conventional and a newly developed ventilators. This newly developed ventilator has combined features of static and turbine ventilators. It is modified from the conventional ventilator, where its top cover is removed and replaced by a low-pressure ventilation device. A Computational Fluid Dynamics (CFD) analysis is performed to explore the flow fields around and inside the rotating and non-rotating ventilators, and the air extraction performance. The air extraction rate is obtained from the mean velocity at the inlet of an open channel, connected to a ventilation tube. Results show that the modified ventilator exhibits better ventilation effects than the conventional one at all of the investigated wind speeds, especially at low speeds. When the ventilator is not rotating, the modified ventilator is still able to extract air out of the ventilator, while the conventional ventilator has negative air extraction rate.

Experimental Evaluation of Turbine Ventilators Performance under Different Test Conditions

One of the most popular wind driven ventilation devices is a turbine ventilator. Its main construction components usually are air suction duct and impeller. However, there are many different configurations of such devices – different shape of vanes and ratios between main dimensions. In order to develop turbine ventilators there is demand for deeper fundamental researches. Major part of previous experimental investigations compares turbine ventilators performance. The aim of presented experimental investigation is to understand key parameters affecting wind driven ventilators performance. For this purpose, straight and curved vane devices under 4 different test conditions are tested. All tests are performed in modified wind tunnel based on the following methodology: 1) testing devices under normal operation conditions; 2) testing without impeller; 3) testing while impeller is stopped; 4) testing while air suction duct is sealed. Experimental results have shown that the biggest part of extracted air flow rate is impacted due to ejection of wind and air suction duct interaction process. A slight increase in performance of turbine ventilators compared to open duct column has been confirmed. Experiments also revealed differences between tested turbine ventilators rotational speed trends. Presented empirical equations of experiments could be used for design of turbine ventilators or other researches purposes.

Are we fully utilizing the functionalities of modern operating room ventilators?

The modern operating room ventilators have become very sophisticated and many of their features are comparable with those of an ICU ventilator. To fully utilize the functionality of modern operating room ventilators, it is important for clinicians to understand in depth the working principle of these ventilators and their functionalities. Piston ventilators have the advantages of delivering accurate tidal volume and certain flow compensation functions. Turbine ventilators have great ability of flow compensation. Ventilation modes are mainly volume-based or pressure-based. Pressure-based ventilation modes provide better leak compensation than volume-based. The integration of advanced flow generation systems and ventilation modes of the modern operating room ventilators enables clinicians to provide both invasive and noninvasive ventilation in perioperative settings. Ventilator waveforms can be used for intraoperative neuromonitoring during cervical spine surgery. The increase in number of new features of modern operating room ventilators clearly creates the opportunity for clinicians to optimize ventilatory care. However, improving the quality of ventilator care relies on a complete understanding and correct use of these new features. VIDEO ABSTRACT: http://links.lww.com/COAN/A47.

Construction of Mechanic Regulation of Turbine Ventilator using Half-Flap

An article deals with a definition, concept, development, calculation and construction of a prototype solution of a mechanical regulation of a turbine ventilator using a half-flap eliminating an amount of ventilated air. The whole mechanical regulation solution lies in a central shaft. When a rotation nozzle is spun to high revolutions, a flap closes gradually and eliminates air flowing. This prototype of the mechanical regulation may be used for classic concepts of turbine ventilators, where the rotation nozzle stays in one position and only rotates around its own axis.The article describes individual development stages from the concept up to construction, including a final visualization of the prototype solution of the mechanical regulation of the turbine ventilator using the half-flap. The mentioned innovative solution of the mechanical regulation is very up-to-date thanks to its simplicity and nonservice operation. It is just the matter of time when one of the producers would be interested in the turbine ventilator solution and it would be introduced into a market space.

Effective use of hybrid turbine ventilator to improve thermal performance in Malaysian tropical houses

An efficient design approach that involves extracting heat build-up in tropical buildings is a means to reduce total dependency on air-conditioning systems. The hybrid turbine ventilator can be regarded as a development technique to address this issue. However, identifying its efficient application in buildings remains questionable. This study aims to develop the research on the hybrid turbine ventilator for the establishment of energy-efficient designs in houses by evaluating its effective use in specific space volume based on several empirical comparisons. The performance of passive and hybrid turbine ventilators in attic space, room, and (attic space + room) with opened and closed windows was compared. The study was conducted in an actual building model, and data were collected onsite with a data acquisition system. The objective was achieved by investigation, and the findings can be used to identify the levels of heat build-up in each strategy. Examination of thermal performance confirmed the appropriate use of the hybrid turbine ventilator in Malaysian landed houses. Practical application:This research contributes directly to energy efficient design in tropical buildings. The outcomes inform a better decision on the effective use of hybrid turbine ventilator in low-rise buildings. The study provides ample evidence on the great potential of using hybrid turbine ventilator by developing its investigation in tropical architecture. The study will assist engineers and architects to evaluate hybrid turbine ventilator performance effectively.

Performance enhancement of rooftop turbine ventilators using wind deflectors

Rooftop turbine ventilators are widely used to improve indoor air quality in residential buildings and industrial complexes. This study presents an approach to enhance the operational performance of commercially available turbine ventilators using wind deflectors. Wind deflectors guide the wind flow to minimize the forces acting on the turbine blades in a negative direction, thereby increasing the rotational speed and exhaust ability of turbine ventilators. Two different prototypes were built and experimentally analyzed, one with adjustable size that covered up to half of the turbine, and one made of flat metal sheets, which were placed in front of the turbine. Compared with traditional turbine ventilators, the results of the two different prototypes showed an average increase in air extraction rate at different wind speeds of 34 and 11%, as well as an average rise in the rotational speed of 36 and 33%, respectively. The present study clearly demonstrates the high potential of wind deflectors to enhance the efficiency of turbine ventilators, and shows that a cover-style wind deflector is the more efficient design.

A review of the potential of attic ventilation by passive and active turbine ventilators in tropical Malaysia

Abstract The strategy of attic ventilation represents one of the techniques to reduce heat build-up in indoor spaces. Its benefit helps to control high energy consumption and improve indoor environment. On the other hand, this approach cannot entirely stop the transfer mechanism of heat from the roof to the attic. Despite this, it is able to reduce its effect depending on the method adopted and the existing environment conditions. The aim of this review is to explore the potential of passive and active turbine ventilators as a technique to overcome heat build-up in tropical buildings. As turbine ventilators represent outlet vents, a ventilated attic would require two systems which are inlet and outlet vents to complete its function. Thus, these two types should be discussed broadly. Through the review, it shows that the hybrid system provides a better solution for Malaysian environment. Therefore, adopting a system that consists of an inlet vent from the gable and an outlet vent using a turbine ventilator with curved vanes comprising of an internal duct, an opening cap with solar panel are preferable. This is due to the fact that this combination creates constant air flow and provides uniform distribution to extract heat effectively.

Evaluation of Ventilators Used During Transport of Critically Ill Patients: A Bench Study

To evaluate the most recent transport ventilators' operational performance regarding volume delivery in controlled mode, trigger function, and the quality of pressurization in pressure support mode. Eight recent transport ventilators were included in a bench study in order to evaluate their accuracy to deliver a set tidal volume under normal resistance and compliance conditions, ARDS conditions, and obstructive conditions. The performance of the triggering system was assessed by the measure of the decrease in pressure and the time delay required to open the inspiratory valve. The quality of pressurization was obtained by computing the integral of the pressure-time curve for the first 300 ms and 500 ms after the onset of inspiration. For the targeted tidal volumes of 300, 500, and 800 mL the errors ranged from -3% to 48%, -7% to 18%, and -5% to 25% in the normal conditions, -4% to 27%, -2% to 35%, and -3% to 35% in the ARDS conditions, and -4% to 53%, -6% to 30%, and -30% to 28% in the obstructive conditions. In pressure support mode the pressure drop range was 0.4-1.7 cm H2O, the trigger delay range was 68-198 ms, and the pressurization performance (percent of ideal pressurization, as measured by pressure-time product at 300 ms and 500 ms) ranges were -9% to 44% at 300 ms and 6%-66% at 500 ms (P < .01). There were important differences in the performance of the tested ventilators. The most recent turbine ventilators outperformed the pneumatic ventilators. The best performers among the turbine ventilators proved comparable to modern ICU ventilators.

An Evaluation of a Proposed Ventilation System for Melbourne's CH2 Building

The understanding of ventilation requirements in commercial buildings has been significantly revised in the last 10-15 years. A link between health, productivity and increased fresh air use has been established by some research and this understanding underpins the ventilation philosophy adopted for the CH2 building. The ventilation system design for CH2 that has been evaluated in this paper envisages a mechanically driven system during the day, using the displacement technique to distribute filtered air. All introduced air will be drawn from outside and no recycling of air will occur. Natural ventilation will be employed at night using the stack effect, enhanced by turbine ventilators. This paper critiques the proposed ventilation system in the light of international experience and the particular conditions of the building's location. The evidence suggests that natural ventilation sometimes may be inadequate to achieve the desired objectives. Minimization of indoor pollutants, adequate filtration and high levels of ventilation should, however, ensure satisfactory air quality during occupied hours.

Opening and Compartmentalization Effects of Internal Pressure in Low-Rise Buildings with Gable and Hip Roofs

AbstractThis study examines how design features, such as building envelope openings and compartmentalization, affect the wind pressure in typical low-rise buildings with gable and hip roofs. Wind-induced internal and external pressures were investigated by using a full-scale wind testing facility generically known as Wall of Wind (WOW). The test-building model was built with an optimal size of 2.74 m (9 ft) long, 2.13 m (7 ft) wide, and 2.13 m (7 ft) high. The model consisted of multiple dominant openings (doors with secondary openings and windows), roof ventilation devices (soffit vents, gooseneck roof vent, and roof turbine ventilators), and horizontal and vertical (ceiling and wall) internal assembly compartments. These features, together with a high Reynolds number (∼106) flow test, enabled a realistic assessment of internal pressures due to (1) dominant openings’ size and location and background leakage and (2) compartmentalization. For the study case, the hatch opening in the roof increased the coef...

Numerical simulation of rooftop ventilator flow

Rotating rooftop turbine ventilators are cost effective environmental friendly natural ventilation devices, which are used to extract airflow from a building to improve air quality and comfort. A CFD study using the standard k- ɛ turbulence model with multiple reference frame (MRF) meshing technique was employed to explore the suitability of numerical approach in modelling various features of a ventilator flow. The initial CFD results were validated against wind tunnel data obtained for a commercial ventilator on a simulated inclined rooftop configuration conducted at the aerodynamic laboratory of University of New South Wales. The numerical studies were then extended to examine both the internal and the external flows associated with the ventilator at different wind speeds and to quantify the performance of a rotating ventilator in terms of air extraction rate. The trend observed appeared to be in good agreement with published data suggesting that application of numerical simulation is feasible as a cost effective tool in the future design, development and performance analysis of rotating wind driven ventilation device.

Simulation of Airflow and Aerodynamic Forces Acting on a Rotating Turbine Ventilator

Problem statement: Rotating turbine ventilators were generally found in most countries. They were simple in structure, light in weight and cheap to install. It was quite surprising that, the aerodynamics of this common device had not been numerically examined and the design process of most of these ventilators had developed progressively through trial and error methods. Approach: This study was concerned with performing simulation of airflow using CFD technique code name FLUENT so as to visualize the flow behavior around and within a rotating turbine ventilator in addition to determining the aerodynamic forces acting on this device during its operation. To achieve that, the realizable k-e and RSM turbulence models were used by taking advantage of moving mesh method to simulate the rotation of turbine ventilator and the consequent results were obtained through the sequential process which ensured accuracy of the computations. Results: The results confirmed that, the realizable k-e model can exhibit a reasonable performance, however not as competence as the RSM model, but of much less computation time. Conclusion/Recommendations: Results from this study, besides ensuring the reliability of utilizing the CFD method in design process of future turbine ventilators, would lead us to a conspicuous progress on increasing the efficiency at reduced cost of wind driven ventilators and similar devices.

Performance testing and comparison of turbine ventilators

A turbine ventilator is a device having a combined function of wind turbine and extract fan. Turbine ventilators are attractive replacements for electrical ventilation fans in terms of using wind energy. They are commonly used in attic, loft and rooftop spaces to facilitate ventilation in buildings at both domestic and industrial level. This study presents measurement of flow rates of four commercial turbine ventilators on a specifically designed experimental system. The ventilation flow rates and rotational speeds are taken at different wind speeds and compared with a simple open column and two standard vent hats. Use of a DC motor to power the ventilators in the absence of wind is described and power consumption against flow rate is given.

A review on wind driven ventilation techniques

Natural ventilation has gained prominence in recent times as a bespoke method of ventilating buildings. The two fundamental principles of natural ventilation are stack effect and wind driven ventilation. This paper reviews miscellaneous wind driven ventilation designs with respect to traditional means such as wind towers and more modern techniques including turbine ventilators and wind catchers. A distinction is made between specific types of wind driven ventilation techniques depending on their operation and mode of engagement with the wind. For example, a static wind catcher is classified as passive; a rotating wind cowl as a directed passive technique and a rotating turbine ventilator is classified as outright active due to its constant rotation with the wind. A table summarising the review is presented at the end with corresponding references.

Assessment of oxygen consumption from standard E cylinders by fluidic, turbine, and compressor style portable mechanical ventilators

Assessment of oxygen consumption from standard E cylinders by fluidic, turbine, and compressor style portable mechanical ventilators