Danielle R S Guerra | Universidade Federal do Pará (original) (raw)

Papers by Danielle R S Guerra

Energy Procedia, 2017

District heating networks are commonly addressed in the literature as one of the most effective s... more District heating networks are commonly addressed in the literature as one of the most effective solutions for decreasing the greenhouse gas emissions from the building sector. These systems require high investments which are returned through the heat sales. Due to the changed climate conditions and building renovation policies, heat demand in the future could decrease, prolonging the investment return period. The main scope of this paper is to assess the feasibility of using the heat demand-outdoor temperature function for heat demand forecast. The district of Alvalade, located in Lisbon (Portugal), was used as a case study. The district is consisted of 665 buildings that vary in both construction period and typology. Three weather scenarios (low, medium, high) and three district renovation scenarios were developed (shallow, intermediate, deep). To estimate the error, obtained heat demand values were compared with results from a dynamic heat demand model, previously developed and validated by the authors. The results showed that when only weather change is considered, the margin of error could be acceptable for some applications (the error in annual demand was lower than 20% for all weather scenarios considered). However, after introducing renovation scenarios, the error value increased up to 59.5% (depending on the weather and renovation scenarios combination considered). The value of slope coefficient increased on average within the range of 3.8% up to 8% per decade, that corresponds to the decrease in the number of heating hours of 22-139h during the heating season (depending on the combination of weather and renovation scenarios considered). On the other hand, function intercept increased for 7.8-12.7% per decade (depending on the coupled scenarios). The values suggested could be used to modify the function parameters for the scenarios considered, and improve the accuracy of heat demand estimations.

DYNA

This study aims to experimentally investigate the effects of using different percentages of ethan... more This study aims to experimentally investigate the effects of using different percentages of ethanol-biodiesel-diesel blends in diesel internal combustion engines and to analyze energy and combustion parameters. The experiments were conducted on a single-cylinder, four-stroke, air-cooled, and constant-speed diesel generator set with a rated electrical power of 4.5 kW and 79% of full engine load (3.54kW). Temperature, fuel flow, AVL pressure, and rotation sensors were installed on the crankshaft and inside the cylinder. The fuels used were commercial diesel (S-10) and blends with 1%, 2%, and 3% of anhydrous ethanol added to diesel, changing the injection pressure in only one blend. The results show a decrease in thermal efficiency and an increase in fuel consumption, in addition to an increase in ignition delay, an increase in combustion duration, a decrease in in-cylinder pressure, and a decrease in the heat release rate as the percentage of ethanol increased.

Gasification [Working Title], 2021

Millions of tons of forest residues, agricultural residues, and municipal solid waste are generat... more Millions of tons of forest residues, agricultural residues, and municipal solid waste are generated in Latin America (LATAM) each year. Regularly, municipal solid waste is diverted to landfills or dumpsites. Meanwhile, forest and agricultural residues end up decomposing in the open air or burnt, releasing greenhouse gases. Those residues can be transformed into a set of energy vectors and organic/chemical products through thermochemical conversion processes, such as pyrolysis and gasification. This book chapter provides information on current examples of gasification on large scale in the world, which typically operate at 700°C, atmospheric pressure, and in a fluidized bed reactor. The produced gas is used for heat and energy generation. Whereas pyrolysis at a large scale operates around 500°C, atmospheric pressure, and in an inert atmosphere, using a fluidized bed reactor. The produced combustible liquid is used for heat and energy generation. The decision of using any of these tec...

Energies

The use of agroforestry residues for energy purposes has long been a reality in Brazil. About 84.... more The use of agroforestry residues for energy purposes has long been a reality in Brazil. About 84.8% of the produced electricity comes from renewable resources; vegetable biomass contributes 9.1% to this total. This percentage has the potential to increase if Amazon biomass residues are processed to be used as fuel. The major difficulty for this scenario is the lack of available information on energy properties, mainly the HHVs for Amazon agroforestry biomass types. Considering that there are important deviations in the equations for predicting the HHVs of Amazon biomass types in the literature, the main objective of this work was to propose equations to determine the HHVs of these biomass types using the proximate or ultimate analysis results as input. The methodology adopted to develop such equations was simple and multiple linear regression methods, using experimental results for HHVs and proximate and ultimate analyses for biomass types from the north region of Brazil. Four disti...

Ambiente Construído, 2021

Resumo A demanda mundial de energia está em constante crescimento, ao mesmo tempo as reservas de ... more Resumo A demanda mundial de energia está em constante crescimento, ao mesmo tempo as reservas de combustíveis fósseis estão diminuindo e não serão suficientes para satisfazer as demandas globais de energia no futuro. Além disso, os sistemas convencionais de aquecimento e refrigeração consomem a maior parte da demanda por energia elevando consideravelmente os custos. O trocador de calor solo-ar (TCSA) é uma opção sustentável que consume menos energia com potencial para melhorar as condições térmicas em edifícios. Apesar de ser uma tecnologia simples e antiga, no Brasil as pesquisas sobre eles são muito limitadas. Nesse contexto, faltam estudos na Região Norte deste país, em particular na cidade de Belém do Pará. Portanto, o objetivo desta pesquisa é desenvolver um modelo numérico tridimensional do TCSA usando ANSYS Fluent para avaliar a influência de parâmetros operacionais e construtivos, tais como a velocidade de escoamento do ar, comprimento e diâmetro do duto no desempenho térmic...

This paper investigates the influence of some governing parameters on the heat transfer character... more This paper investigates the influence of some governing parameters on the heat transfer characteristics of a circular impinging jet on a heated flat plate. Measurements of local pressure and wall temperature distributions are presented as well as temperature profiles. The experiments were conducted at various nozzle-to-plate spaces and Reynolds number of 35,000. The constant wall heat flux condition is achieved by conducting electricity through thin resistors that are placed beneath an aluminum disk. Temperature was measured using thermocouples.

Universidade Federal do Para, Instituto de Tecnologia (ITEC), Faculdade de Engenharia Mecânica (FEM)

A sonda de pressão multifuros é um instrumento padrão para medidas de pressão estática, velocidad... more A sonda de pressão multifuros é um instrumento padrão para medidas de pressão estática, velocidade e direção em escoamentos complexos. Entretanto são encontradas no mercado com alto custo quando comparadas com os tubos de Pitot. O objetivo deste trabalho é o de descrever o procedimento de calibração e medição usando uma sonda de pressão multifuros no mapeamento da pressão e da velocidade em um escoamento em túnel de vento de seção aberta. O método utilizado é o proposto por Treaster & Yocum (1979), os dados foram obtidos a partir das medidas de pressão obtidas por uma sonda de cinco furos. Os furos da sonda são constituídos de agulhas hipodérmicas de 0,9mm de diâmetro externo e 0,5mm de diâmetro interno. A calibração foi realizada na seção de teste de um túnel de vento nas combinações de ângulos de desvio e direção na faixa de-30º a 30º. Palavras chave: sonda de pressão, velocidade, calibração.

Energy & Fuels, 2013

International Journal of Heat and Mass Transfer, 2005

The present work investigates the applicability of scaling log-laws to the turbulent impinging je... more The present work investigates the applicability of scaling log-laws to the turbulent impinging jet. Both, the velocity and the temperature fields are studied under this assumption. To validate the proposed expressions, a detailed experimental program was carried out based on thermal anemometry. The experiments were conducted for one nozzleto-plate spacing (H/D = 2.0) and Reynolds number of 35,000. A constant wall heat flux condition was achieved by conducting electricity through thin resistors that were placed beneath an aluminum disk. Measurements of local velocity and of temperature distributions are presented as well as longitudinal turbulence profiles. The mean temperature profiles were measured through thermocouples.

The objective of this work was to evaluate the potential of electric energy from biomass residues... more The objective of this work was to evaluate the potential of electric energy from biomass residues available in an Amazonian community, currently with a maximum demand of 56 kW. The chosen community is called Santo Antônio. A 200 kW plant with biomass residues from the sawmill was installed in that community as part of a government program called Light for All (Progama Luz para Todos). The chosen community has working sawmills, which generate wood residues. The plant was designed according to the volume of waste available. An extensive mass and volume balance of the residue from the sawmill activity was conducted. For the evaluation of the energy potential, the overall efficiency of the power plant was estimated using the specific consumption of the steam turbine and the boiler efficiency. The study showed that at the highest production period 66% of the wood log processed by the Santo Antonio's sawmill turns into waste resulting in 104 kW of potential electrical power. The study also concluded that there is a 12% decrease in the volume of wood processed in periods of lower production. Even so, the amount of biomass available would be sufficient to provide the electric power to the community. The study demonstrates that a biomass plant is feasible for the supply of Electric Energy to small Amazonian communities, avoiding the construction of energy subtransmission systems in regions of native forest. The work can be replicated to other rural communities, in regions still without access to electricity but with availability of biomass.

Article history: Received 18 December 2016 Accepted 16 February 2017 Available online 28 February... more Article history: Received 18 December 2016 Accepted 16 February 2017 Available online 28 February 2017

International Journal of Hydrogen Energy

Brazilian Journal of Development

Proceedings of the 25th International Congress of Mechanical Engineering